HK1231055B - Process for making isoquinoline compounds - Google Patents

Description

Method for preparing isoquinoline compounds

This application claims priority to U.S. patent application No. 61/672,191, filed on July 16, 2012; this application is a divisional application of Chinese patent application No. 201310302822.0, filed on July 15, 2013, and entitled "Methods for Preparing Isoquinoline Compounds."

Technical Field

The present invention relates to a process for preparing isoquinoline compounds and intermediate compounds obtained therefrom.

Background Art

Isoquinoline compounds are known to be effective in treating and preventing conditions and disorders associated with HIF, including anemia and tissue damage caused by ischemia and/or hypoxia (see, e.g., Robinson et al. (2008) Gastroenterology 134(1):145–155; Rosenberger et al. (2008) Nephrol Dial Transplant 23(11):3472-3478). Specifically, the compounds and methods disclosed herein can be used as or for preparing isoquinoline compounds that inhibit HIF hydroxylase activity, thereby increasing the stability and/or activity of hypoxia-inducible factor (HIF), which can be used to treat and prevent conditions and disorders associated with HIF.

To date, many synthetic routes for preparing substituted isoquinoline compounds have been published. In 1966, Caswell et al. (Heterocyclyl Chem 1966, (3), 328-332) reported the synthesis of 4-hydroxy-3-carbonylmethoxy-1(2H)-isoquinoline and its 6- and 8-methoxy-substituted derivatives via a Gabriel-Coleman rearrangement reaction of phthalimidoacetate with sodium in methanol, preferably at elevated temperature (105°C) in a sealed reaction vessel. This method does provide an excess of regioisomers, but the degree of substitution is governed by the electronic properties of the substituents, rather than what one skilled in the art would expect.

In 1978, Suzuki et al. (Synthesis 1978 (6), 461-462) reported the synthesis of 4-hydroxy-3-carbomethoxy-1(2H)-isoquinoline via acid-catalyzed ring opening and subsequent intramolecular cyclization of 4-methoxycarbonyl-1,3-oxazole (prepared from phthalic anhydride and methyl isocyanoacetate). Suzuki et al. also reported the synthesis of nitro-substituted 4-hydroxy-3-carbomethoxy-1(2H)-isoquinoline, but the method disclosed therein provided a mixture of 6- and 7-nitroisoquinoline compounds.

Weidmann et al. (U.S. Patent No. 6,093,730) reported the following synthesis of various substituted isoquinoline-3-amides: chromatographic separation of the 4-hydroxy-3-carbomethoxy-1(2H)-isoquinoline isomers provided by the synthesis by Caswell et al., followed by hydrolysis of the methyl ester, activation of the corresponding acid to the acid halide, and condensation with glycine methyl ester.

Other methods for preparing substituted isoquinoline compounds have been reported in US Patent 7,629,357 and US Patent 7,928,120. US Patent 7,928,120 teaches the preparation of substituted cyanoisoquinoline compounds by reacting an optionally substituted 2-methylbenzoate with a halogenating agent to provide the corresponding 2-(halomethyl)benzoate, followed by reaction with an N-protected glycine ester, and finally cyclization/aromatization using a base and an optional oxidizing agent. This method is superior to the aforementioned literature in that the disclosed method only provides a single isomer of a 5-, 6-, 7-, or 8-substituted isoquinoline compound. However, only halogen and cyano substituents are provided at the 1-position of the isoquinoline. US Patent 7,629,357 discloses a method for synthesizing different substituents at the 1-position of various substituted isoquinoline compounds, including 1-methylisoquinoline compounds. The 1-methylisoquinoline compound of US Patent 7629357 is prepared as follows: first, the corresponding 1,4-dihydroxyisoquinoline compound is reacted with phosphorus oxychloride or phosphorus oxybromide to provide a 1-chloro or 1-bromoisoquinoline compound, which is then methylated using trimethylboroxine with tetrakis(triphenylphosphine)palladium or an excess of n-butyllithium and then methyl iodide.

SUMMARY OF THE INVENTION

The present invention relates to methods for the safe and efficient large-scale synthesis of various substituted isoquinoline compounds and intermediate compounds obtained therefrom. Specifically, the methods disclosed herein provide the desired 5-, 6-, 7-, or 8-substituted isoquinoline compounds as single regioisomers without the need for chromatographic separation and without the use of reagents such as phosphorus oxychloride, phosphorus oxybromide, n-butyllithium, or trimethylboroxine, which can be unsafe and/or expensive when used on a large scale.

Also provided are novel intermediate compounds obtained by the methods. The compounds disclosed herein can be used as or in the preparation of isoquinoline compounds that inhibit HIF hydroxylase activity, thereby increasing the stability and/or activity of hypoxia-inducible factor (HIF). Such compounds can be used to treat disorders associated with ischemia and hypoxia, and for treating erythropoietin-related disorders, including anemia, etc. (see, for example, US Patent No. 7,629,357).

In one aspect, the present invention relates to a process for preparing a compound of formula I or a stereoisomer thereof or a mixture of stereoisomers thereof:

The method comprises contacting a compound of formula II with a compound of formula III under conditions sufficient to produce a compound of formula I:

in

Z is O, NR ¹ or S;

^R1 is selected from hydrogen and alkyl;

^R2 is selected from hydrogen and alkyl which is unsubstituted or substituted with one or more substituents independently selected from cycloalkyl, heterocyclyl, aryl and heteroaryl;

R ³ and R ⁴ are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO— or —SO ₂ —, then R ⁸ is not hydrogen; and

R ⁹ is selected from hydrogen, alkyl and aryl;

or R ³ and R ⁴ together with the carbon atoms pendant thereto form a cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl;

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl, and -X ² R ¹⁰ ;

wherein X ² is oxygen, -S(O) _n - or -NR ¹³ -;

n is 0, 1, or 2;

R ¹⁰ is selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl; and

R ¹³ is selected from hydrogen, alkyl and aryl;

or when X ² is —NR ¹³ —, then R ¹⁰ and R ¹³ together with the nitrogen atom to which they are attached may combine to form a heterocyclyl or substituted heterocyclyl group; and

Each R ¹¹ is independently selected from an alkyl group, a benzyl group or an aryl group, or two R ^{11 s} together with the nitrogen atom to which they are attached form a 4-8 membered heterocyclic group or heteroaryl group.

In another aspect, the present invention relates to a process for preparing a compound of formula IV or a stereoisomer or a mixture of stereoisomers thereof:

The method comprises contacting a compound of Formula I with one of the following under conditions sufficient to produce a compound of Formula IV:

(a) a compound of formula, followed by a compound of formula;

(b) a compound of formula R ¹² -X ³ , followed by a compound of formula; or

(c) Compounds of formula V:

in

X ³ is a halogen;

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl, or when there are two R ¹² , the two R ¹² together with the carbon atom to which they are attached form a 4-8 membered heterocyclyl; and

Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I.

In another aspect, the present invention relates to a process for preparing a compound of formula VI or a stereoisomer or a mixture of stereoisomers thereof:

The method comprises converting a compound of formula IV under conditions sufficient to produce a compound of formula VI:

in

Z, ^R1 , ^R2 , ^R3 , ^R4 , ^R5 , ^R6 , ^R8 , ^R9 , ^R10 , ^R11 , ^R13 , n, ^X1 and ^X2 are as defined above in Formula I; and

R ¹² is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic groups.

In another aspect, the present invention relates to a compound of formula VIII, or a salt, ester, stereoisomer or stereoisomer mixture thereof:

in:

Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I;

R ⁷ is —N(R ¹¹ )(R ¹¹ ) or —OC(O)R ¹² ; and

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl;

with the proviso that the compound is not 1-dimethylaminomethyl-4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester.

Additional embodiments of the invention are described throughout this document.

Detailed Description of the Invention

Before describing compounds and methods, it should be understood that the invention is not limited to the specific compounds, compositions, methods, protocols, cell lines, assays, and reagents described, as they may vary. It should also be understood that the terminology used herein is intended to describe specific embodiments of the invention and is not intended to limit the scope of the invention as described in the appended claims.

definition

It must be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

Unless otherwise defined, all scientific and technical terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the methods, devices and materials described herein are preferred. All public documents cited herein are incorporated herein by reference in their entirety for the purpose of describing and disclosing the methods, reagents and tools reported in the literature that may be used in conjunction with the present invention. This does not mean that the existing inventions disclose the content of the present invention in advance.

Unless otherwise indicated, the practice of the present invention will employ conventional methods of chemistry, biochemistry, molecular biology, cell biology, genetics, immunology and pharmacology, which are within the skill of the art and which are fully explained in the literature. See, e.g., Gennaro, A. R., ed. (1990) Remington's Pharmaceutical Sciences, 18th ed., Mack Publishing Co.; Colowick, S. et al., eds., Methods In Enzymology, Academic Press, Inc.; D. M. Weir, and C. C. Blackwell, eds. (1986) Handbook of Experimental Immunology, Vols. I-IV, Blackwell Scientific Publications; Maniatis, T. et al., eds. (1989) Molecular Cloning: A Laboratory Manual, 2nd ed., Vols. I-III, Cold Spring Harbor Laboratory Press; Ausubel, F. M. et al., eds. (1999) Short Protocols in Molecular Biology, 4th ed., John Wiley &Sons; Ream et al., eds. (1998) Molecular Biology Techniques: An Intensive Laboratory Course, Academic Press; Newton & Graham eds. (1997) PCR (Introduction to Biotechniques Series), 2nd edition, Springer Verlag.

The term "alkyl" refers to a saturated monovalent hydrocarbon radical having 1 to 10 carbon atoms, more specifically 1 to 5 carbon atoms and even more specifically 1 to 3 carbon atoms. This term is exemplified by groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, and the like.

The term "substituted alkyl" refers to an alkyl group having 1 to 10 carbon atoms, more specifically 1 to 5 carbon atoms, and having 1 to 5 substituents or 1 to 3 substituents, each of which is independently selected from alkoxy, substituted alkoxy, acyl, acylamino, acyloxy, amino, substituted amino, aminoacyl, aminocarbonylamino, aminothiocarbonylamino, aminocarbonyloxy, aryl, substituted aryl, aryloxy, substituted aryloxy, aryloxyaryl, substituted aryloxyaryl, cyano, halogen, hydroxy, nitro, oxo, thioxo, hioxo), carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl, thio, alkylthio, substituted alkylthio, arylthio, substituted arylthio, cycloalkylthio, substituted cycloalkylthio, heteroarylthio, substituted heteroarylthio, heterocyclicthio, substituted heterocyclicthio, sulfonyl, substituted sulfonyl, heteroaryl, substituted heteroaryl, heterocycle, substituted heterocycle, cycloalkoxy, substituted cycloalkoxy, heteroaryloxy, substituted heteroaryloxy, heterocycleoxy, substituted heterocycleoxy, oxycarbonylamino, oxythiocarbonylamino, -OS(O) -OS(O) _{2 -} substituted alkyl, -OS(O) ₂ -aryl, -OS(O) ₂ -substituted aryl, -OS(O) ₂ -heteroaryl, -OS(O) ₂ -substituted heteroaryl, -OS(O) ₂ -heterocycle, -OS(O) ₂ -substituted ^{heterocycle and -OSO2-NR40R40 ,} _-NR40S ⁽ O) _2- ^NR40 -alkyl, ^-NR40S (O)2 ^-NR40 -substituted alkyl, ^-NR40S (O) ₂ - ^NR40 -aryl, ^-NR40S (O) _{2 -} ^NR40 -substituted aryl, -NR40S(O) _2- ^NR40 -heteroaryl, ^-NR40S (O) _2- ^NR40 -substituted heteroaryl, ^-NR40S (O) ₂ - ^NR40 -substituted ⁴⁰ -heterocycle and -NR ⁴⁰ S(O) ₂ -NR ⁴⁰ -substituted heterocycle, wherein each R ⁴⁰ is independently selected from hydrogen or alkyl. This group is exemplified by groups such as trifluoromethyl, benzyl, pyrazol-1-ylmethyl, and the like.

The term "alkoxy" refers to the group "alkyl-O-" which includes, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, and the like.

The term "substituted alkoxy" refers to the group "substituted alkyl-O-."

The term "acyl" refers to the groups H-C(O)-, alkyl-C(O)-, substituted alkyl-C(O)-, alkenyl-C(O)-, substituted alkenyl-C(O)-, alkynyl-C(O)-, substituted alkynyl-C(O)-, cycloalkyl-C(O)-, substituted cycloalkyl-C(O)-, aryl-C(O)-, substituted aryl-C(O)-, heteroaryl-C(O)-, substituted heteroaryl-C(O), heterocycle-C(O)-, and substituted heterocycle-C(O)-, provided that the nitrogen atom of the heterocycle or substituted heterocycle is not attached to the -C(O)- group, and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle are as defined herein.

The term "aminoacyl" or "amide" or the prefix "carbamoyl,""carboxamide,""substitutedcarbamoyl," or "substituted carboxamide" refers to the group -C(O) ^NR42R42 , wherein ^{each R42} is independently selected from hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle; or wherein each ^R42 is combined to form a heterocycle or substituted heterocycle together with the nitrogen atom, wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle are as defined herein.

The term "acyloxy" refers to the groups alkyl-C(O)O-, substituted alkyl-C(O)O-, alkenyl-C(O)O-, substituted alkenyl-C(O)O-, alkynyl-C(O)O-, substituted alkynyl-C(O)O-, aryl-C(O)O-, substituted aryl-C(O)O-, cycloalkyl-C(O)O-, substituted cycloalkyl-C(O)O-, heteroaryl-C(O)O-, substituted heteroaryl-C(O)O-, heterocycle-C(O)O-, and substituted heterocycle-C(O)O-, wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle are as defined herein.

The term "alkenyl" refers to an ethylenically unsaturated monovalent hydrocarbon radical having 2-6 carbon atoms or 2-4 carbon atoms and having at least 1 or 1-2 sites of vinyl (>C=C<) unsaturation. Examples of such groups are vinyl (vinyl-1-yl), allyl, but-3-enyl, and the like. Where appropriate, this term includes both E (trans) and Z (cis) isomers. It also includes mixtures of both E and Z components.

The term "substituted alkenyl" refers to an alkenyl group having 1-3 substituents or 1-2 substituents selected from alkoxy, substituted alkoxy, acyl, acylamino, acyloxy, amino, substituted amino, aminoacyl, aryl, substituted aryl, aryloxy, substituted aryloxy, cyano, halogen, hydroxy, nitro, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle. Suitably, this term includes both E (trans) and Z (cis) isomers. It also includes mixtures of both E and Z components.

The term "alkynyl" refers to an acetylenically unsaturated monovalent hydrocarbon radical having 2-6 carbon atoms or 2-3 carbon atoms and having at least 1 or 1-2 sites of acetylenic (-C≡C-) unsaturation. Examples of this group include ethyn-1-yl, propyn-1-yl, propyn-2-yl, and the like.

The term "substituted alkynyl" refers to an alkynyl group having 1-3 substituents or 1-2 substituents selected from alkoxy, substituted alkoxy, acyl, acylamino, acyloxy, amino, substituted amino, aminoacyl, aryl, substituted aryl, aryloxy, substituted aryloxy, cyano, halogen, hydroxy, nitro, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle. This group is exemplified by groups such as phenylethynyl.

The term "amino" refers to the group _-NH2 .

The term "substituted amino" refers to ^the group ^-NR41R41 , where each ^R41 is independently selected from hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, substituted heterocycle, sulfonyl, and substituted sulfonyl, or the ^R41 group can be combined with the nitrogen atom to form a heterocycle or a substituted heterocycle; provided that not both ^R41 groups are hydrogen. This group is exemplified by phenylamino, tolylamino, and the like. This group is further exemplified by groups such as (acet-2-yl)amino.

The term "acylamino" refers to the groups -NR ⁴⁵ C(O)alkyl, -NR ⁴⁵ C(O)substituted alkyl, -NR ⁴⁵ C(O)cycloalkyl, -NR ⁴⁵ C(O)substituted cycloalkyl, -NR ⁴⁵ C(O)alkenyl, -NR ⁴⁵ C(O)substituted alkenyl, -NR ⁴⁵ C(O)alkynyl, -NR ⁴⁵ C(O)substituted alkynyl, -NR ⁴⁵ C(O)aryl, -NR ⁴⁵ C(O)substituted aryl, -NR ⁴⁵ C(O)heteroaryl, -NR ⁴⁵ C(O)substituted heteroaryl, -NR ⁴⁵ C(O)heterocycle, and -NR ⁴⁵ C(O)substituted heterocycle, wherein R ⁴⁵ is hydrogen or alkyl, and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle and substituted heterocycle are as defined herein.

The term "oxycarbonylamino" refers to the groups ^-NR46C (O)O-alkyl, ^{-NR46C(O)O-substituted alkyl, -NR46C (} O)O-alkenyl, -NR46C(O)O-substituted alkenyl, ^-NR46C (O)O-alkynyl, ^-NR46C (O)O-substituted alkynyl, ^-NR46C (O)O-cycloalkyl, ^-NR46C (O)O-substituted cycloalkyl, ^-NR46C (O)O-aryl, ^-NR46C (O)O-substituted aryl, ^-NR46C (O)O-heteroaryl, ^-NR46C (O)O-substituted heteroaryl, ^-NR46C (O)O-heterocycle, and ^-NR46C (O)O-substituted heterocycle ^, wherein R ⁴⁶ is hydrogen or alkyl, and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle and substituted heterocycle are as defined herein.

The term "thiocarbonylamino" refers to the groups -NR ⁴⁶ C(S)O-alkyl, -NR ⁴⁶ C(S)O-substituted alkyl, -NR ⁴⁶ C(S)O-alkenyl, -NR ⁴⁶ C(S)O-substituted alkenyl, -NR ⁴⁶ C(S)O-alkynyl, -NR ⁴⁶ C(S)O-substituted alkynyl, -NR ⁴⁶ C(S)O-cycloalkyl, -NR ⁴⁶ C(S)O-substituted cycloalkyl, -NR ⁴⁶ C(S)O-aryl, -NR ⁴⁶ C(S)O-substituted aryl, -NR ⁴⁶ C(S)O-heteroaryl, -NR ⁴⁶ C(S)O-substituted heteroaryl, -NR ⁴⁶ C(S)O-heterocycle, and -NR ⁴⁶ C(S)O-substituted heterocycle, wherein R ⁴⁶ is hydrogen or alkyl, and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle and substituted heterocycle are as defined herein.

The term "aminocarbonyloxy" or the prefix "carbamoyloxy" or "substituted carbamoyloxy" refers to the group -OC(O) ^NR47R47 , wherein each ^R47 is independently selected from hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, ^and substituted heterocycle; or wherein each ^R47 is combined to form a heterocycle or substituted heterocycle together with the nitrogen atom, and wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle are as defined herein.

The term "aminocarbonylamino" refers to the group ^-NR49C (O)N( ^R49 ) ₂ , wherein each ^R49 is independently selected from hydrogen and alkyl.

The term "aminothiocarbonylamino" refers to the group ^-NR49C (S)N( ^R49 ) ₂ , wherein each ^R49 is independently selected from hydrogen and alkyl.

The term "aryl" or "aryl (Ar)" refers to a monovalent aromatic carbocyclic group of 6-14 carbon atoms having a single ring (e.g., phenyl) or multiple fused rings (e.g., naphthyl or anthracenyl), which may or may not be aromatic (e.g., 2-benzoxazolinone, 2H-1,4-benzoxazin-3(4H)-on-7-yl, etc.), provided that the point of attachment is the aryl group. Preferred aryl groups include phenyl and naphthyl.

As defined herein, the term "substituted aryl" refers to an aryl group substituted with 1 to 4, particularly 1 to 3, substituents selected from the group consisting of hydroxy, acyl, acylamino, acyloxy, alkyl, substituted alkyl, alkoxy, substituted alkoxy, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, amidino (-C(=NH)-amino or substituted amino), amino, substituted amino, aminoacyl, aminocarbonyloxy, aminocarbonylamino, aminothiocarbonylamino, aryl, substituted aryl, aryloxy, substituted aryloxy, cycloalkoxy, substituted cycloalkoxy, heteroaryloxy, substituted substituted heteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy, carboxyl, carboxyl ester, cyano, thio, alkylthio, substituted alkylthio, arylthio, substituted arylthio, heteroarylthio, substituted heteroarylthio, cycloalkylthio, substituted cycloalkylthio, heterocyclylthio, substituted heterocyclylthio, cycloalkyl, substituted cycloalkyl, guanidino (-NH-C(=NH)-amino or substituted amino), halogen, nitro, heteroaryl, substituted heteroaryl, heterocycle, substituted heterocycle, oxycarbonylamino, oxythiocarbonylamino, sulfonyl, substituted sulfonyl, -OS(O) -OS(O) ₂ -substituted alkyl, -OS(O) ₂ -aryl, -OS(O) ₂ -substituted aryl, -OS(O) ₂ -heteroaryl _, -OS(O) ₂ -substituted heteroaryl, -OS(O) ₂ -heterocycle, -OS(O) ₂ -substituted ^heterocycle and -OSO2 _- ^NR51R51 , ^-NR51S (O) _2- ^NR51 -alkyl, ^-NR51S (O)2 ^-NR51 -substituted alkyl, ^-NR51S (O) _2- ^NR51 -aryl, -NR51S(O) _{2 -} ^NR51 -substituted aryl, ^-NR51S (O) _2- ^NR51 -heteroaryl, ^-NR51S (O) _2- ^NR51 -substituted heteroaryl, ^-NR51S (O) ₂ - ^NR51 -substituted ^-NR51 -heterocycle, ^-NR51S (O) _2- ^NR51 -substituted heterocycle, wherein each ^R51 is independently selected from hydrogen or alkyl, wherein each term is as defined herein. This group is exemplified by groups such as 4-fluorophenyl, 3-methoxyphenyl, 4-methoxyphenyl, 4-tert-butylphenyl, 4-trifluoromethylphenyl, 2-trifluoromethoxyphenyl, 3-trifluoromethoxyphenyl, 4-trifluoromethoxyphenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2-chloro-6-fluorophenyl, 2,4-dichlorophenyl, 3,5-difluorophenyl, 4-methoxyphenyl, 3-cyanophenyl, 4-cyanophenyl, 4-phenoxyphenyl, 4-methanesulfonylphenyl, and biphenyl-4-yl.

The term "aryloxy" refers to the group aryl-O- which includes, for example, phenoxy, naphthoxy, and the like.

The term "substituted aryloxy" refers to a substituted aryl-O- group.

The term "aryloxyaryl" refers to the group -aryl-O-aryl.

The term "substituted aryloxyaryl" refers to aryloxyaryl groups substituted with 1 to 3 substituents on either or both aryl rings, wherein the aryl rings are as defined above for substituted aryl.

The term "carboxyl" refers to -COOH or a salt thereof.

The term "carboxyl ester" refers to the groups -C(O)O-alkyl, -C(O)O-substituted alkyl, -C(O)O-alkenyl, -C(O)O-substituted alkenyl, -C(O)O-alkynyl, -C(O)O-substituted alkynyl, -C(O)O-cycloalkyl, -C(O)O-substituted cycloalkyl, -C(O)O-aryl, -C(O)O-substituted aryl, -C(O)O-heteroaryl, -C(O)O-substituted heteroaryl, -C(O)O-heterocycle, and -C(O)O-substituted heterocycle.

The term "cyano" refers to the group -CN.

The term "cycloalkyl" refers to a saturated or unsaturated but non-aromatic cycloalkyl group having 3-10, 3-8 or 3-6 carbon atoms, which has a single ring or multiple rings, including, for example, adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, cyclohexenyl, etc.

The term "substituted cycloalkyl" refers to a cycloalkyl group having 1-5 substituents selected from the group consisting of oxo (=O), thioxo (=S), alkyl, substituted alkyl, alkoxy, substituted alkoxy, acyl, acylamino, acyloxy, amino, substituted amino, aminoacyl, aryl, substituted aryl, aryloxy, substituted aryloxy, cyano, halogen, hydroxy, nitro, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocycle, and substituted heterocycle.

The term "cycloalkoxy" refers to an -O-cycloalkyl group.

The term "substituted cycloalkoxy" refers to an -O-substituted cycloalkyl group.

The term "halo" or "halogen" refers to fluorine, chlorine, bromine or iodine.

The term "hydroxy" refers to the group -OH.

The term "heteroaryl" refers to an aromatic ring of 1 to 15 carbon atoms or 1 to 10 carbon atoms, and has 1 to 4 heteroatoms selected from oxygen, nitrogen and sulfur in the ring. Such heteroaryl can have a single ring (e.g., pyridyl, furyl or thienyl) or multiple fused rings (e.g., indolizinyl or benzothienyl), provided that the point of attachment is through a ring containing heteroatoms, and the ring is aromatic. Nitrogen and/or sulfur ring atoms can optionally be oxidized to provide N-oxides or sulfoxide and sulfone derivatives. Examples of heteroaryl include, but are not limited to, pyridyl, pyrimidyl, pyrrolyl, pyrazolyl, indolyl, thiophenyl, thienyl and furyl.

The term "substituted heteroaryl" refers to a heteroaryl group substituted with 1 to 3 substituents selected from the same substituent groups as defined for substituted aryl. This group is exemplified by groups such as 5-fluoro-pyridin-3-yl, 1-benzyl-1H-[1,2,3]triazol-4-yl, 5-bromo-furan-2-yl, trifluoromethyl-2H-pyrazol-3-yl, and the like.

The term "heteroaryloxy" refers to the group -O-heteroaryl and "substituted heteroaryloxy" refers to the group -O-substituted heteroaryl.

The terms "heterocyclyl" and "heterocycle" are used interchangeably herein. As used herein, the term refers to a saturated or unsaturated (but non-aromatic) group having a single ring or multiple fused rings, having 1-10 carbon atoms, and having 1-4 heteroatoms in the ring selected from nitrogen, sulfur or oxygen, wherein in the fused ring system, one or more of the rings may be aryl or heteroaryl, provided that the point of attachment is on the heterocycle. The nitrogen and/or sulfur ring atoms may optionally be oxidized to provide N-oxides or sulfoxide and sulfone derivatives.

The term "substituted heterocyclyl" or "substituted heterocycle" refers to a heterocyclyl group substituted with 1 to 3 substituents as defined for substituted cycloalkyl.

Examples of heterocyclic and heteroaryl groups include, but are not limited to, azetidinyl, pyrrolyl, imidazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolizinyl, isoindolyl, indolyl, indolinyl, indazolyl, purinyl, quinolizinyl, isoquinolinyl, quinolinyl, phthalazinyl, naphthylpyridinyl, quinoxalinyl, quinazolinyl, cinnozinyl, pteridinyl, carbazolyl, carbolinyl, phenanthridinyl, acridinyl, phenanthrolinyl, isothiazolyl, , phenazinyl, isoxazolyl, phenoxazinyl, phenothiazinyl, imidazolidinyl, imidazolinyl, piperidinyl, piperazinyl, indolyl, phthalimide, 1,2,3,4-tetrahydroisoquinolinyl, 4,5,6,7-tetrahydrobenzo[b]thiophenyl, thiazolyl, thiazolinyl, phenylthio, benzo[b]phenylthio, morpholinyl, thiomorpholinyl (also referred to as thiomorpholinyl), piperidinyl, pyrrolidinyl, tetrahydrofuranyl, etc.

The term "nitro" refers to the group _-NO2 .

The term "oxo" refers to the atom (=O) or the atom ( ^-O- ).

The term "sulfonyl" refers to the group -S(O) _2H . The term "substituted sulfonyl" refers to the groups _-SO2 -alkyl, _-SO2 -substituted alkyl, -SO2-alkenyl, _-SO2 -substituted alkenyl, _-SO2 -alkynyl, _-SO2 -substituted alkynyl, _-SO2 -cycloalkyl, _-SO2 -substituted cycloalkyl, _-SO2 -cycloalkenyl, _-SO2 -substituted cycloalkenyl, _-SO2 -aryl, _-SO2 -substituted aryl, -SO2-heteroaryl, _-SO2 -substituted heteroaryl, _-SO2 -heterocycle, _-SO2 -substituted heterocycle, wherein alkyl, substituted alkyl, _alkenyl , substituted alkenyl, _alkynyl , substituted alkynyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl are as defined herein. Substituted sulfonyl groups include groups such as methyl- _SO2- , phenyl- _SO2- , and 4-methylphenyl- _SO2- .

The term "heterocycleoxy" refers to the group -O-heterocycle, and "substituted heterocycleoxy" refers to the group -O-substituted heterocycle.

The term "thio" or "mercapto" refers to the group -SH.

The term "alkylthio," "alkylthio," or "thioether" refers to the group -S-alkyl, wherein alkyl is as defined above.

The term "substituted alkylthio," "substituted alkylthio," or "substituted alkylthio" refers to the group -S-substituted alkyl, wherein substituted alkyl is as defined above.

The term "cycloalkylthio" or "cycloalkylsulfanyl" refers to the group -S-cycloalkyl, where cycloalkyl is as defined above.

The term "substituted cycloalkylthio" refers to the group -S-substituted cycloalkyl, wherein substituted cycloalkyl is as defined above.

The term "arylthio" or "arylthio" refers to the group -S-aryl, and "substituted arylthio" refers to the group -S-substituted aryl, wherein aryl and substituted aryl are as defined above.

The term "heteroarylthio" or "heteroarylthio" refers to the group -S-heteroaryl, and "substituted heteroarylthio" refers to the group -S-substituted heteroaryl, wherein heteroaryl and substituted heteroaryl are as defined above.

The term "heterocyclethio" or "heterocyclethio" refers to the group -S-heterocycle, and "substituted heterocyclethio" refers to the group -S-substituted heterocycle, wherein heterocycle and substituted heterocycle are as defined above.

The term "ester" refers to compounds disclosed herein that include the group ^-COOR54 , wherein ^R54 is alkyl or substituted alkyl.

The term "amine" refers to an organic compound that includes a basic nitrogen atom with a lone pair of electrons. Amines are derivatives of ammonia in which one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. The basic nitrogen atom can also be part of a heterocyclic or heteroaryl ring.

It should be understood that in all of the above-defined substituted groups, polymers obtained by defining the substituents themselves with additional substituents (e.g., a substituted aryl having a substituted aryl as a substituent, which is itself substituted with a substituted aryl, etc.) are not intended to be included. Also not included is an unlimited number of substituents, whether the substituents are the same or different. In such cases, the maximum number of such substituents is 3. Each of the above definitions is therefore subject to certain limitations, for example, substituted aryl is limited to -substituted aryl-(substituted aryl)-substituted aryl.

It should also be understood that the above definition is not intended to include impermissible substitution patterns (e.g., a methyl group substituted with five fluoro groups, or a hydroxyl group alpha to vinyl or ethynyl unsaturation). Such impermissible substitution patterns are well known to those skilled in the art.

The terms compound and molecule are used interchangeably. When the wording "molecule" or "compound" is used, other forms contemplated by the present invention are salts, prodrugs, solvates, tautomers, stereoisomers, and mixtures of stereoisomers. In some embodiments, the salt is a pharmaceutically acceptable salt.

The term "pharmaceutically acceptable" refers to properties and/or substances that are acceptable to a patient (eg, a human patient) from a toxicological and/or safety standpoint.

The term "salt" refers to salts of the compounds of the present invention, which can be prepared with relatively nontoxic acids or bases, depending on the specific substituents found on the compounds described herein. When the compounds of the present invention contain relatively acidic functionalities (e.g., -COOH groups), base addition salts can be obtained by contacting the compound (e.g., a neutralized form of such a compound) with a sufficient amount of the desired base (either neat or in a suitable inert solvent). Examples of pharmaceutically acceptable base addition salts include lithium, sodium, potassium, calcium, ammonium, organic amino, magnesium, and aluminum salts, among others. When the compounds of the present invention contain relatively basic functionalities (e.g., amines), acid addition salts can be obtained, for example, by contacting the compound (e.g., a neutralized form of such a compound) with a sufficient amount of the desired acid (either neat or in a suitable inert solvent). Examples of pharmaceutically acceptable acid addition salts include those derived from inorganic acids such as hydrochloric acid, hydrobromic acid, nitric acid, carbonic acid, monohydrogencarbonic acid, phosphoric acid, diphosphoric acid, monohydrogenphosphoric acid, dihydrogenphosphoric acid, sulfuric acid, monohydrogensulfuric acid, hydroiodic acid, and the like, as well as salts derived from relatively nontoxic organic acids such as formic acid, acetic acid, propionic acid, isobutyric acid, malic acid, maleic acid, malonic acid, benzoic acid, succinic acid, suberic acid, fumaric acid, lactic acid, mandelic acid, phthalic acid, benzenesulfonic acid, p-toluenesulfonic acid, citric acid, tartaric acid, methanesulfonic acid, 2-hydroxyethylsulfonic acid, salicylic acid, stearic acid, and the like. Also included are salts of amino acids such as arginine salts and the like, and salts of organic acids such as glucuronic acid or galacturonic acid, and the like (see, for example, Berge et al., Journal of Pharmaceutical Science, 1977, 66: 1-19). Certain specific compounds of the present invention contain both basic and acidic functionalities, which allow the compounds to be converted into either base or acid addition salts. Additionally, counterions can be exchanged using conventional methods known in the art.

The neutral form of the compound can be regenerated, for example, by contacting the salt with a base or acid and isolating the parent compound in a conventional manner. The parent form of the compound may have certain physical properties that differ from those of the different salt forms, such as solubility in polar solvents, but otherwise, the salts are equivalent to the parent form of the compound for the purposes of this disclosure.

When a compound includes a negatively charged oxygen atom "O- ^" , such as in " ^-COO- ", the formula represents the optional inclusion of a proton or an organic or inorganic cationic counterion (e.g., Na ⁺ ). In one embodiment, the compound is pharmaceutically acceptable in salt form. In addition, when a compound of the present invention includes an acidic group, such as a carboxylic acid group, such as the substituent "-COOH", " _-CO2H " or "-C(O) _2H ", the formula represents the optional inclusion of the corresponding "deprotonated" form of the acidic group, such as " ^-COO- ", " _-CO2- " or "-C(O) _2- ^" , ^respectively .

Similarly, when a compound includes a positively charged nitrogen atom "N ⁺ ", the formula may optionally include an organic or inorganic anionic counterion (e.g., Cl ^- ). In one embodiment, the salt form of the compound formed is pharmaceutically acceptable. In addition, when a compound of the present invention includes a basic group such as an amine, the formula may optionally include the corresponding "protonated" form of the basic group, such as "NH ⁺ ".

The compounds of the present invention may exist in all tautomeric forms and therefore all tautomeric forms and tautomeric mixtures are included in the compounds disclosed therein.

Compounds of the present invention can also exist in concrete geometric shape or stereoisomeric form. The present invention contemplates all such compounds, including cis- and trans-isomers, (-)- and (+)-enantiomers, diastereomers, (D)-isomers, (L)-isomers, its racemic mixture and other mixtures thereof, as rich in enantiomerical or diastereomeric mixtures, fall within the scope of the present invention. In addition, asymmetric carbon atoms can be present in substituents such as alkyl. All such isomers and mixtures thereof are intended to be included in the present invention. When compounds as herein described comprise olefinic double bonds or other geometric asymmetric centers, and unless otherwise clearly indicated, it is intended that the compound include both E and Z geometric isomers.

Optically active (R)- and (S)-isomers and d and l isomers can be prepared using chiral synthetic fibers or chiral reagents, or resolved using conventional techniques. The resolution of the racemate can be accomplished, for example, by conventional methods, such as crystallization in the presence of a resolving agent; chromatographic analysis using, for example, a chiral HPLC column; or derivatizing the racemic mixture with a resolving agent to produce diastereomers, separating the diastereomers via chromatography, and removing the resolving agent to produce the initial compound enriched in enantiomer form. Any of the above procedures can be repeated to improve the enantiomeric purity of the compound. If, for example, a specific enantiomeric compound of the present invention is desired, it can be prepared by asymmetric synthesis or by derivatization with a chiral auxiliary, wherein the diastereomeric mixture formed is separated, and the auxiliary group is cracked to provide the pure desired enantiomer. Alternatively, in cases where the molecule contains a basic functional group such as an amino group or an acidic functional group such as a carboxyl group, diastereomeric salts can be formed with appropriate optically active acids or bases, followed by resolution of the diastereomers thus formed by fractional crystallization or chromatography means known in the art, and subsequent recovery of the pure enantiomers. Additionally, separation of enantiomers and diastereomers is often accomplished using chromatography using a chiral stationary phase, optionally in combination with chemical derivatization (e.g., formation of carbamates from amines).

The term "reaction conditions" is intended to represent the physical and/or environmental conditions under which a chemical reaction is carried out. Examples of reaction conditions include, but are not limited to, one or more of the following: temperature of reaction, solvent, pH, pressure, reaction time, reactant molar ratio, base or acid, or the presence of a catalyst. Reaction conditions can be named after the specific chemical reaction in which they are used, such as coupling conditions, hydrogenation conditions, acylation conditions, reduction conditions, etc. The reaction conditions for most reactions are typically known to those skilled in the art or can be easily obtained through the literature. It is also contemplated that the reaction conditions may include reagents other than those listed for the specific reaction.

The term "amino protecting group" refers to those organic groups whose purpose is to protect the nitrogen atom against undesirable reactions during the synthetic method, and includes, but is not limited to, silyl ethers such as 2-(trimethylsilyl)ethoxymethyl (SEM) ether, or alkoxymethyl ethers such as methoxymethyl (MOM) ether, tert-butoxymethyl (BUM) ether, benzyloxymethyl (BOM) ether, or methoxyethoxymethyl (MEM) ether. Additional protecting groups include tert-butyl, acetyl, benzyl, benzyloxycarbonyl (carbonylbenzyloxy, CBZ), p-methoxybenzyloxycarbonyl, p-nitrobenzyloxycarbonyl, tert-butoxycarbonyl (BOC), trifluoroacetyl, and the like.

Certain protecting groups are preferred over others due to their convenience or relative ease of removal, or due to their steric effects in subsequent processing steps. Additional suitable amino protecting groups are taught in T. W. Greene and P. G. M. Wuts, Protecting Groups in Organic Synthesis, 3rd ed., Wiley, New York, 1999, and references cited therein, which are hereby incorporated by reference in their entirety.

The term "anhydrous reaction conditions" is intended to mean reaction conditions in which water is excluded. Such conditions are known to those skilled in the art and typically include one or more dry or distilled solvents and reagents, a dry reaction vessel, and/or the presence of a desiccant such as activated molecular sieves, magnesium sulfate, sodium sulfate, and the like.

The term "hydrogenation conditions" or "hydrogenation reaction conditions" is intended to mean suitable conditions and catalysts for forming one or more new C-H bonds. Hydrogenation conditions or hydrogenation reaction conditions typically include catalysts such as those based on platinum group metals (platinum, palladium, rhodium, and ruthenium) (e.g., Pd/C or _PtO2 ).

The term "inert atmosphere" is intended to mean an atmosphere comprising gases that do not react with the reactants and reagents during the desired reaction process. Typically, an inert atmosphere does not include oxygen and/or moisture. Exemplary gases include nitrogen and argon.

The term "under pressure" is intended to mean reaction conditions carried out at a pressure greater than 1 atmosphere. Such reactions can be carried out in a Parr hydrogenator or in a sealed reaction vessel (i.e., a screw-capped flask) where the reaction is carried out under heating to allow the solvent to evaporate to increase the pressure in the reaction vessel.

The term "acid" is intended to represent a chemical substance that can contribute a proton or accept a pair of electrons from another substance. Examples of acids include organic acids, such as carboxylic acids (e.g., lactic acid, acetic acid, formic acid, citric acid, oxalic acid, uric acid, etc.) and sulfonic acids (e.g., methanesulfonic acid, p-toluenesulfonic acid), inorganic acids (e.g., hydrochloric acid, nitric acid, phosphoric acid, sulfuric acid, boric acid, hydrofluoric acid, hydrobromic acid), Lewis acids, etc. The term "Lewis acid" is used herein to represent a molecule or ion that can form a covalent bond with two electrons from a second molecule or ion, and bind to another molecule or ion. For methods of the present invention, Lewis acids are considered to be substances lacking electrons that can accept a pair of electrons. Examples of Lewis acids that can be used for the present invention are metal cations and their complexes, including magnesium, calcium, aluminum, zinc, titanium, chromium, copper, boron, tin, mercury, iron, manganese, cadmium, gallium, and barium. Their complexes can include hydroxides, alkyls, alkoxides, halides, and organic acid ligands such as acetate. Examples of preferred Lewis acids for use in the process of the invention are titanium alkoxides, in particular Ti(OEt) _{4 ,} which additionally have dehydrating properties.

The term "base" is intended to refer to a chemical substance that is a proton acceptor. Suitable bases for use in the present invention include inorganic or organic bases. Examples of inorganic bases include, but are not limited to, potassium hydroxide (KOH), barium hydroxide (Ba(OH) ₂ ), cesium hydroxide (CsOH), sodium hydroxide (NaOH), strontium hydroxide (Sr(OH) ₂ ), calcium hydroxide (Ca(OH) ₂ ), lithium hydroxide (LiOH), rubidium hydroxide (RbOH), and magnesium hydroxide (Mg(OH) ₂ ). Organic bases can be neutral or negatively charged compounds, which typically include nitrogen atoms such as amines and nitrogen-containing heterocyclic compounds. Examples of neutral nitrogen-containing organic bases include ammonia, pyridine, methylamine, imidazole, 2,2,6,6-tetramethylpiperidine, 4-(dimethylamino)pyridine, and the like. Examples of negatively charged organic bases include alkyl lithium reagents, dialkyl lithium amides, alkyl lithium oxides, alkyl magnesium halides, and the like.

method

The present invention provides methods for synthesizing various substituted isoquinoline compounds, and intermediate compounds obtained thereby. The methods enable safe and efficient large-scale preparation of isoquinoline compounds, e.g., for the anticipated commercial production of such compounds.

One advantage of the present method over previously disclosed methods is that the present method does not require separation of regioisomers. For example, the methods disclosed in Suzuki et al. (supra), Weidmann et al. (supra), and U.S. Patent No. 7,629,357 provide a mixture of regioisomers of 5- and 8-substituted isoquinoline compounds or 6- and 7-substituted isoquinoline compounds, which are then separated using conventional chromatography. However, such separations are not ideal, as the maximum theoretical yield of the step is only 50%.

Another advantage of the inventive method over those previously disclosed is that the method disclosed in the present invention does not use harmful and/or expensive reagents. Specifically, the method disclosed in the present invention avoids the halogenation step and therefore avoids reagents such as phosphorus oxychloride and phosphorus oxybromide (see, for example, the synthesis previously disclosed in US Patent No. 7,323,475, which is described in Scheme E herein, E-400 to E-500). These reagents are extremely destructive to the tissues of mucous membranes, upper respiratory tract, eyes, and skin. In addition, the method avoids reagents such as n-butyl lithium and trimethylcyclotriboroxine, both of which require special processing procedures because they have very large reactivity with respect to moisture. Therefore, the method disclosed in the present invention is superior to the method of this type of non-ideal reagents.

The method of the present invention uses a starting compound, which can be prepared from readily available starting materials or compounds disclosed herein using, for example, the following general methods and procedures. It will be appreciated that given typical or preferred processing conditions (i.e., reaction temperature, time, reactant molar ratio, solvent, pressure, etc.), other processing conditions may be used unless otherwise indicated. Optimum reaction conditions may vary with the specific reactants or solvents used, but such conditions may be determined by conventional optimization procedures by those skilled in the art.

In addition, it is obvious to those skilled in the art that, in order to prevent some functional groups from experiencing undesirable reactions, conventional protecting groups can be necessary. Suitable protecting groups for different functional groups and suitable conditions for protecting and deprotecting specific functional groups are well known in the art. For example, numerous protecting groups are described in T.W.Greene and G.M.Wuts (1999) Protecting Groups in Organic Synthesis, the 3rd edition, Wiley, New York and the references cited therein.

In addition, the method of the present invention can use compounds comprising one or more chiral centers. Therefore, if desired, such compounds can be prepared or separated as pure stereoisomers, i.e., as single enantiomers or diastereomers, or as mixtures enriched in stereoisomers. All such stereoisomers (and enriched mixtures) are included within the scope of the present invention unless otherwise indicated. Pure stereoisomers (or enriched mixtures) can be prepared using, for example, optically active starting materials or stereoselective reagents well known in the art. Alternatively, the racemic mixture of such compounds can be separated using, for example, chiral column chromatography, chiral resolving agents, etc.

The starting materials for the following reactions are generally known compounds or can be prepared by known procedures or their obvious variations. For example, many starting materials are available from commercial suppliers such as Aldrich Chemical Co. (Milwaukee, Wisconsin, USA), Bachem (Torrance, California, USA), Emka-Chemce or Sigma (St. Louis, Missouri, USA). Others can be prepared by the procedures described in conventional reference texts, such as Fieser and Fieser's Reagents for Organic Synthesis, Volumes 1-15 (John Wiley, and Sons, 1991), Rodd's Chemistry of Carbon Compounds, Volumes 1-5, and Supplements (Elsevier Science Publishers, 1989), Organic Reactions, Volumes 1-40 (John Wiley, and Sons, 1991), March's Advanced Organic Chemistry, (John Wiley, and Sons, 5th edition, 2001), and Larock's Comprehensive Organic Transformations (VCH Publishers Inc., 1989), or obvious variations thereof.

In one aspect, the present invention relates to a process for preparing a compound of formula I or a stereoisomer or a mixture of stereoisomers thereof:

The method comprises contacting a compound of Formula II with a compound of Formula III under conditions sufficient to produce a compound of Formula I:

in

Z is O, NR ¹ or S;

^R1 is selected from hydrogen and alkyl;

^R2 is selected from hydrogen and alkyl, which is unsubstituted or substituted with one or more substituents independently selected from cycloalkyl, heterocyclyl, aryl and heteroaryl;

R ³ and R ⁴ are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO— or —SO ₂ —, then R ⁸ is not hydrogen; and

R ⁹ is selected from hydrogen, alkyl and aryl;

or R ³ and R ⁴ together with the carbon atoms pendant thereto form a cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl;

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl, and -X ² R ¹⁰ ;

wherein X ² is oxygen, -S(O) _n - or -NR ¹³ -;

n is 0, 1, or 2;

R ¹⁰ is selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl; and

R ¹³ is selected from hydrogen, alkyl and aryl;

or when X ² is —NR ¹³ —, then R ¹⁰ and R ¹³ together with the nitrogen atom to which they are attached may combine to form a heterocyclyl or substituted heterocyclyl group; and

Each R ¹¹ is independently selected from an alkyl group, a benzyl group or an aryl group, or two R ^{11 s} together with the nitrogen atom to which they are attached form a 4-8 membered heterocyclic group or heteroaryl group.

In a specific embodiment, the present invention is directed to a process for preparing a compound of formula IA, or a stereoisomer or mixture of stereoisomers thereof:

It comprises contacting a compound of Formula IIA with a compound of Formula III under conditions sufficient to produce a compound of Formula IA:

wherein R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I.

The reaction can be carried out in glacial acetic acid or a polar aprotic solvent such as dioxane, tetrahydrofuran (THF), dimethylformamide (DMF) or dimethylacetamide (DMAc) to produce a compound of Formula I or IA with or without an acid catalyst. In certain embodiments, the reaction conditions include an acid. The acid can be selected from, for example, acetic acid, trifluoroacetic acid, sulfuric acid, hydrochloric acid or an acidic ion exchange resin. In various embodiments, about 0.1-14 molar equivalents of acid can be used. In some embodiments, the acid is glacial acetic acid. In some embodiments, at least about 2 molar equivalents of glacial acetic acid are used. In specific embodiments, about 7-about 8 molar equivalents of glacial acetic acid are used.

In certain embodiments, the reaction is carried out under an inert atmosphere such as argon or nitrogen. In some embodiments, the reaction is carried out under a nitrogen atmosphere.

In certain embodiments, the reaction conditions are anhydrous reaction conditions. Such conditions typically include drying reagents (e.g., molecular sieves), the reaction is carried out under an inert atmosphere, etc. Such methods are well known in the art.

In certain embodiments, the reaction is carried out at a temperature between room temperature (approximately 25° C.) and 110° C. and a pressure between 0 and 60 psi. In some embodiments, the reaction is carried out at an elevated temperature (i.e., a temperature greater than about 30° C.). For example, the temperature range can be about 50° C. to about 60° C.

In certain embodiments, about 1.1 to about 1.5 molar equivalents of the compound of Formula III are used.

In certain embodiments, the reaction is carried out in glacial acetic acid at a temperature ranging from about 50°C to about 60°C; and R ¹¹ of the compound of formula III is C ₁ -C ₄ alkyl.

In certain embodiments, the reaction is carried out in glacial acetic acid under a nitrogen atmosphere at a temperature range of about 50°C to about 60°C; and R ¹¹ of the compound of formula III is C ₁ -C ₄ alkyl.

In certain embodiments, the reaction is carried out in about 7 to about 8 molar equivalents of glacial acetic acid at a temperature range of about 50°C to about 60°C and using about 1.1 to about 1.5 molar equivalents of a compound of formula III wherein R ¹¹ is C ₁ -C ₄ alkyl.

In certain embodiments, the reaction is carried out in about 7 to about 8 molar equivalents of glacial acetic acid under a nitrogen atmosphere at a temperature range of about 50°C to about 60°C and using about 1.1 to about 1.5 molar equivalents of a compound of formula III wherein R ¹¹ is C ₁ -C ₄ alkyl.

In certain embodiments, R ¹¹ of the compound of formula III is C ₁ -C ₄ alkyl. In certain embodiments, the compound of formula III includes a compound of formula IIIA:

In another aspect, the present invention relates to a process for preparing a compound of formula IV or a stereoisomer or a mixture of stereoisomers thereof:

The method comprises contacting a compound of Formula I with one of the following under conditions sufficient to produce a compound of Formula IV:

(a) a compound of formula, followed by contacting with a compound of formula;

(b) a compound of formula R ¹² -X ³ , followed by contacting with a compound of formula; or

(c) Compounds of formula V:

in

X ³ is a halogen;

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl, or when there are two R ¹² , the two R ¹² together with the carbon atom to which they are attached form a 4-8 membered heterocyclyl; and

Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I.

In one embodiment, the present invention relates to a process for preparing a compound of formula IVA, or a stereoisomer or mixture of stereoisomers thereof:

It comprises contacting a compound of Formula IA with a compound of Formula V under conditions sufficient to produce a compound of Formula IVA:

in

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl, or when there are two R ¹² , the two R ¹² together with the carbon atom to which they are attached form a 4-8 membered heterocyclyl; and

R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I.

The reaction can be carried out in glacial acetic acid or a polar aprotic solvent such as dioxane, THF, DMF or DMAc with or without an acid catalyst. In certain embodiments, the reaction conditions include an acid. The acid can be selected from, for example, acetic acid, trifluoroacetic acid, sulfuric acid, hydrochloric acid or an acidic ion exchange resin. In various embodiments, about 0.1-14 molar equivalents of acid can be used. In some embodiments, the acid is glacial acetic acid. In some embodiments, at least about 2 molar equivalents of glacial acetic acid are used. In specific embodiments, about 7-about 8 molar equivalents of glacial acetic acid are used.

In certain embodiments, the reaction is carried out under an inert atmosphere, such as an argon or nitrogen atmosphere. In some embodiments, the reaction is carried out under a nitrogen atmosphere.

In certain embodiments, the reaction conditions are anhydrous reaction conditions. Such conditions typically include drying reagents (e.g., molecular sieves), the reaction is carried out under an inert atmosphere, etc. Such methods are well known in the art.

In certain embodiments, the reaction is carried out at an elevated temperature (ie, at a temperature greater than about 30° C.). For example, in certain embodiments, the temperature is about 100° C.

In various embodiments, about 1 to about 4 molar equivalents of the compound of Formula V are used. In specific embodiments, when the compound of Formula I or IA is isolated prior to the reaction, about 1 molar equivalent of the compound of Formula V is used. In other embodiments, about 2 to about 3 molar equivalents of the compound of Formula V are used. In certain embodiments, the compound of Formula V comprises acetic anhydride.

In certain embodiments, the reaction conditions include a compound of Formula V, wherein R ¹² is C ₁ -C ₄ alkyl; and the reaction is carried out at an elevated temperature.

In certain embodiments, the reaction conditions include a compound of Formula V, wherein R ¹² is C ₁ -C ₄ alkyl; and the reaction is carried out at a temperature of about 100°C.

In certain embodiments, the reaction conditions include a compound of Formula V, wherein R ¹² is C ₁ -C ₄ alkyl; and the reaction is carried out under an inert atmosphere and at an elevated temperature. In certain embodiments, the additional compound of Formula V is acetic anhydride.

In certain embodiments, the reaction conditions include about 2 to about 3 molar equivalents of a compound of Formula V, wherein R ¹² is C ₁ -C ₄ alkyl, and the reaction is carried out at a temperature of about 100° C. In certain embodiments, the additional compound of Formula V is acetic anhydride.

In certain embodiments, the reaction conditions include about 2 to about 3 molar equivalents of a compound of Formula V, wherein R ¹² is C ₁ -C ₄ alkyl, and the reaction is carried out under a nitrogen atmosphere at a temperature of about 100° C. In certain embodiments, the additional compound of Formula V is acetic anhydride.

In certain embodiments, the reaction conditions further comprise converting the compound of Formula VII to the compound of Formula IV under conditions sufficient to produce the compound of Formula IV:

wherein Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I; and

R ¹² is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic groups.

In certain embodiments, the reaction conditions further comprise converting the compound of Formula VIIA to the compound of Formula IVA under conditions sufficient to produce the compound of Formula IVA:

wherein R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I; and

R ¹² is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic groups.

In certain embodiments, the reaction is carried out in a solvent selected from dichloromethane, ethyl acetate or THF. In a specific embodiment, the solvent is dichloromethane.

In certain embodiments, the reaction conditions include an amine. In certain embodiments, the amine is morpholine. In certain embodiments, the reaction is carried out at a temperature of about 0°C to about 10°C.

In certain embodiments, the reaction conditions comprise morpholine; and the reaction is carried out in dichloromethane at a temperature of about 0°C to about 10°C.

In another aspect, the present invention relates to a process for preparing a compound of formula VI or a stereoisomer or a mixture of stereoisomers thereof:

The method comprises converting a compound of formula IV under conditions sufficient to produce a compound of formula VI:

wherein Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I; and

R ¹² is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic groups.

In another embodiment, the present invention is directed to a process for preparing a compound of formula VIA, or a stereoisomer or mixture of stereoisomers thereof:

It comprises converting a compound of formula IVA under conditions sufficient to produce a compound of formula VIA:

wherein R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I; and

R ¹² is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic groups.

In certain embodiments, the reaction conditions for producing VI or VIA are hydrogenation conditions. Such conditions typically include hydrogen. Such conditions also typically include a catalyst, such as a palladium catalyst (e.g., Pd/C, also known as palladium (0) supported on carbon). Alternatively, Pd(OH) ₂ /C or Raney nickel can be used.

In certain embodiments, the reaction conditions include a solvent selected from dichloromethane, ethyl acetate, or methanol. In specific embodiments, the reaction conditions include dichloromethane. In specific embodiments, the reaction conditions include ethyl acetate.

In some embodiments, the reaction is carried out under a hydrogen atmosphere and pressure, for example, at about 20 to about 300 psi or at about 60 psi. In some embodiments, the reaction conditions include a base such as sodium carbonate or sodium bicarbonate. In some embodiments, the hydrogenation reaction conditions include about 0.5 to about 1 molar equivalent of sodium carbonate.

In certain embodiments, the reaction conditions include hydrogen, sodium carbonate, ethyl acetate, Pd/C, and pressure.

In certain embodiments, the reaction conditions include hydrogen, sodium carbonate, ethyl acetate, Pd/C, and a pressure of about 60 psi.

In certain embodiments, the present invention is a method for preparing a compound of formula VI, or a stereoisomer or mixture of stereoisomers thereof:

It includes the following steps:

a) contacting a compound of formula II with a compound of formula III under reaction conditions sufficient to provide a compound of formula I

b) contacting the compound of formula I with one of the following under conditions sufficient to produce the compound of formula IV:

(i) a compound of formula, a compound of the following formula;

(ii) a compound of the formula R ¹² -X ³ , or a compound of the following formula; or

(iii) Compounds of formula V:

c) optionally converting the compound of formula VII into a compound of formula IV; and

d) converting the compound of formula IV under conditions sufficient to produce the compound of formula VI;

in

X ³ is a halogen;

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl, or when there are two R ¹² , the two R ¹² together with the carbon atom to which they are attached form a 4-8 membered heterocyclyl; and

Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I.

In certain embodiments, the present invention is a method for preparing a compound of formula VIA, or a stereoisomer or mixture of stereoisomers thereof:

It includes the following steps:

a) contacting a compound of formula IIA with a compound of formula III under reaction conditions to provide a compound of formula IA

b) contacting a compound of Formula IA with a compound of Formula V under conditions sufficient to produce a compound of Formula IVA;

c) optionally converting the compound of formula VIIA into a compound of formula IVA; and

d) converting the compound of formula IVA under conditions sufficient to produce the compound of formula VIA;

wherein R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I; and

R ¹² is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic groups.

In certain embodiments, the present invention is a method for preparing a compound of formula VIC, or a stereoisomer or mixture of stereoisomers thereof:

It includes the following steps:

a) contacting a compound of formula IIC with a compound of formula IIIA under reaction conditions sufficient to provide a compound of formula IC;

b) contacting a compound of Formula IC with a compound of Formula VA under conditions sufficient to produce a compound of Formula IVC;

c) optionally converting the compound of formula VIIC into a compound of formula IVC;

and

d) converting the compound of formula IVC under conditions sufficient to produce the compound of formula VIC;

in

^R2 is selected from hydrogen and alkyl, which is unsubstituted or substituted with one or more substituents independently selected from cycloalkyl, heterocyclyl, aryl and heteroaryl; and

R ⁴ is selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO— or —SO ₂ —, then R ⁸ is not hydrogen; and

^R9 is selected from hydrogen, alkyl and aryl.

In certain embodiments, the present invention is a method for preparing a compound of formula VID, or a stereoisomer or mixture of stereoisomers thereof:

It includes the following steps:

a) contacting a compound of formula IID with a compound of formula IIIA under reaction conditions to provide a compound of formula ID;

b) contacting a compound of Formula ID with a compound of Formula VA under conditions sufficient to produce a compound of Formula IVD;

c) optionally converting the compound of formula VIID into a compound of formula IVD;

and

d) converting the compound of formula IVD under conditions sufficient to produce the compound of formula VID;

in

^R2 is selected from hydrogen and alkyl, which is unsubstituted or substituted with one or more substituents independently selected from cycloalkyl, heterocyclyl, aryl and heteroaryl; and

R ³ is selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO— or —SO ₂ —, then R ⁸ is not hydrogen; and

^R9 is selected from hydrogen, alkyl and aryl.

In certain embodiments of the above methods, ^R2 is hydrogen.

In certain embodiments of the above methods, ^R2 is alkyl.

In certain embodiments of the above methods, R ³ is phenoxy.

In certain embodiments of the above methods, R ³ is 4-methoxyphenoxy.

In certain embodiments of the above methods, R ³ is 3,5-difluorophenoxy.

In certain embodiments of the above methods, R ⁴ is phenoxy.

In certain embodiments of the above methods, R ⁴ is 4-methoxyphenoxy.

In certain embodiments of the above methods, R ⁴ is 3,5-difluorophenoxy.

In certain embodiments of the above methods, R ² is hydrogen and R ³ is phenoxy.

In certain embodiments of the above methods, ^R2 is hydrogen and ^R3 is 4-methoxyphenoxy.

In certain embodiments of the above methods, R ² is hydrogen and R ³ is 3,5-difluorophenoxy.

In certain embodiments of the above methods, R ² is hydrogen and R ⁴ is phenoxy.

In certain embodiments of the above methods, R ² is hydrogen and R ⁴ is 4-methoxyphenoxy.

In certain embodiments of the above methods, R ² is hydrogen and R ⁴ is 3,5-difluorophenoxy.

In certain embodiments of the methods described herein, the compound of Formula VI is represented by Formula VIB:

wherein R ² , R ³ and R ⁴ are as defined in formula I above.

In certain embodiments of the above methods, the compound of Formula II is represented by Formula IIB:

wherein R ² , R ³ and R ⁴ are as defined in formula I above.

In certain embodiments of the above methods, the compound of formula III is represented by formula IIIA:

In certain embodiments of the above methods, the compound of formula III is represented by:

or

In certain embodiments of the above methods, the compound of Formula I is represented by Formula IB:

wherein R ² , R ³ , R ⁴ and R ¹¹ are as defined in formula I above.

In certain embodiments of the above methods, the compound of formula V is represented by formula VA:

In certain embodiments of the above methods, the compound of Formula V is represented by:

or

In certain embodiments of the above methods, the compound of Formula VII is represented by Formula VIIB:

wherein R ² , R ³ and R ⁴ are as defined above in formula I, and R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclic groups.

In certain embodiments of the above methods, the compound of formula IV is represented by formula IVB:

wherein R ² , R ³ and R ⁴ are as defined above in formula I, and R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclic groups.

In an alternative embodiment, the present invention relates to a method for preparing a compound of formula X or a stereoisomer or mixture of stereoisomers thereof, and pharmaceutically acceptable salts, stereoisomers, mixtures of stereoisomers and esters thereof:

It includes the following steps:

a) contacting a compound of formula II with a compound of formula III under reaction conditions sufficient to provide a compound of formula I;

b) contacting the compound of formula I with one of the following under conditions sufficient to produce the compound of formula IV:

(iv) a compound of formula, followed by a compound of formula;

(v) a compound of formula R ¹² -X ³ , followed by a compound of formula; or

(vi) a compound of formula V;

c) optionally converting the compound of formula VII into a compound of formula IV;

d) converting the compound of formula IV under conditions sufficient to produce the compound of formula VI; and

e) contacting a compound of formula VI with a compound of formula under reaction conditions sufficient to provide a compound of formula X;

wherein Z, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , n, X ¹ and X ² are as defined above in Formula I;

X ³ is a halogen;

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl, or when there are two R ¹² , the two R ¹² together with the carbon atom to which they are attached form a 4-8 membered heterocyclyl;

When ^Ra is -COOH, p is 0; when ^Ra is -WR ¹⁸ , p is 1;

W is selected from oxygen, -S(O) _n- , and ^-NR19- , wherein n is 0, 1, or 2, ^R19 is selected from hydrogen, alkyl, substituted alkyl, acyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, and ^R18 is selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, or when W is ^-NR19- , then ^R18 and ^R19, together with the nitrogen atom to which they are attached, may combine to form a heterocyclyl or substituted heterocyclyl group;

R is selected from hydrogen, deuterium and methyl;

R' is selected from hydrogen, deuterium, alkyl, and substituted alkyl; alternatively, R and R' and the carbon atoms pendant thereto may be combined to form a cycloalkyl, substituted cycloalkyl, heterocyclyl, or substituted heterocyclyl group; and

R" is selected from hydrogen and alkyl, or R" together with R' and the nitrogen pendant thereto may combine to form a heterocyclyl or substituted heterocyclyl group.

In another embodiment, the present invention is directed to a process for preparing methyl 4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxylate (3e):

It includes the following steps:

a) contacting a compound of formula 3a with a compound of formula IIIA under conditions sufficient to produce a compound of formula 3b;

b) contacting a compound of Formula 3b with a compound of Formula VA under conditions sufficient to produce a compound of Formula 3c;

c) converting the compound of formula 3d, optionally under conditions sufficient to produce the compound of formula 3c; and

d) converting the compound of formula 3c under conditions sufficient to produce the compound of formula 3e.

In another embodiment, the present invention is a process for preparing 2-(4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxamido)acetic acid (3f).

which comprises contacting a compound of formula 3e with glycine or sodium glycinate under conditions sufficient to produce a compound of formula 3f;

Compounds of formula II used in the methods disclosed herein can be prepared according to published procedures (see, for example, US Patent No. 7,323,475, which is incorporated herein by reference in its entirety):

In certain embodiments of the methods disclosed above, each of R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ , R ⁹ and R ¹⁰ is defined as follows:

R ³ and R ⁴ are independently selected from hydrogen, alkyl, cycloalkyl, heterocyclyl, aryl, heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ; wherein

X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, aryl, cycloalkyl, heteroaryl, and heterocyclyl, provided that when X ¹ is -SO- or -SO ₂ -, then R ⁸ is not hydrogen; and

R ⁹ is selected from hydrogen, alkyl and aryl;

or R ³ and R ⁴ together with the carbon atoms pendant thereto form a cycloalkyl, heterocyclyl, aryl or heteroaryl group;

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, alkoxy, aryl, heteroaryl and -X ² R ¹⁰ ; wherein

X ² is oxygen, -S(O) _n - or -NR ¹³ -;

n is 0, 1, or 2;

R ¹⁰ is selected from alkyl, aryl, heteroaryl and heterocyclyl; and

R ¹³ is selected from hydrogen, alkyl and aryl;

or when X ² is -NR ¹³ -, then R ¹⁰ and R ¹³ together with the nitrogen atom to which they are attached may combine to form a heterocyclyl group;

wherein each of the above alkyl, alkoxy, cycloalkyl, heterocyclic, aryl, heteroaryl and heterocyclic groups may be optionally substituted with 1-3 R ¹⁰⁰ ,

wherein each R ¹⁰⁰ is independently selected from alkoxy, acyl, acylamino, acyloxy, amino, aminoacyl, aminocarbonylamino, aminothiocarbonylamino, aminocarbonyloxy, aryl, aryloxy, aryloxyaryl, cyano, halogen, hydroxy, nitro, oxo, thioxo, carboxyl, carboxyl ester, cycloalkyl, thio, alkylthio, arylthio, cycloalkylthio, heteroarylthio, heterocyclic heterocyclic thio, sulfonyl, heteroaryl, heterocyclic heterocyclic, cycloalkyloxy, heteroaryloxy, heterocyclic oxy, oxycarbonylamino, oxythiocarbonylamino, -OS(O) 2 -alkyl, -OS(O) ₂ -aryl, -OS(O) ₂ -heteroaryl, -OS(O) ₂ -heterocyclyl, -OSO ₂ -NR ⁴⁰ R ⁴⁰ , ^{-NR 40} _S (O) ₂ -NR ⁴⁰ -alkyl, -NR ⁴⁰ S(O) ₂ - ^NR40 -aryl, ^-NR40S (O) _2- ^NR40 -heteroaryl, and ^-NR40S (O) ₂ - ^NR40 -heterocyclyl, wherein each ^R40 is independently selected from hydrogen or alkyl.

In certain embodiments of the above methods, R ¹ is hydrogen.

In certain embodiments of the above methods, ^R2 is hydrogen or alkyl.

In certain embodiments of the above methods,

R ³ and R ⁴ are independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO— or —SO ₂ —, then R ⁸ is not hydrogen; and

R ⁹ is selected from hydrogen, alkyl and aryl;

Alternatively, R ³ and R ⁴ together with the carbon atoms pendant thereto form a cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl.

In certain embodiments of the above methods,

R ³ and R ⁴ are independently selected from hydrogen, alkyl, aryl, heteroaryl, hydroxy, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ; wherein

X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

^R8 is aryl or substituted aryl; and

R ⁹ is hydrogen, alkyl or aryl;

Alternatively, ^R3 and ^R4 together with the carbon atoms pendant thereto form a cycloalkyl, heterocyclyl, aryl or heteroaryl group.

In certain embodiments of the above methods,

R ³ and R ⁴ are independently selected from hydrogen and -X ¹ R ⁸ ; wherein X ¹ is oxygen, and R ⁸ is aryl or substituted aryl.

In certain embodiments of the above methods,

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, and —X ² R ¹⁰ ; wherein X ² is oxygen, —S(O) _n —, or —NR ¹³ —;

n is 0, 1, or 2;

R ¹⁰ is aryl or substituted aryl; and

R ¹³ is selected from hydrogen, alkyl and aryl.

In certain embodiments of the above methods,

R ⁵ and R ⁶ are independently selected from hydrogen and -X ² R ¹⁰ ; wherein X ² is oxygen, and R ¹⁰ is aryl or substituted aryl.

In certain embodiments of the above methods, R ⁵ and R ⁶ are hydrogen.

In certain embodiments of the above methods,

^R2 is hydrogen or alkyl;

R ³ and R ⁴ are independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO— or —SO ₂ —, then R ⁸ is not hydrogen; and

R ⁹ is selected from hydrogen, alkyl and aryl;

or ^R3 and ^R4 together with the carbon atoms pendant thereto form a cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl or substituted heteroaryl; and

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, and -X ² R ¹⁰ ;

wherein X ² is oxygen, -S(O) _n - or -NR ¹³ -;

n is 0, 1, or 2;

R ¹⁰ is aryl or substituted aryl; and

R ¹³ is selected from hydrogen, alkyl and aryl.

In certain embodiments of the above methods,

^R2 is hydrogen or alkyl;

R ³ and R ⁴ are independently selected from hydrogen, alkyl, aryl, heteroaryl, hydroxy, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ; wherein

X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

^R8 is aryl or substituted aryl; and

R ⁹ is hydrogen, alkyl or aryl;

or ^R3 and ^R4 together with the carbon atoms pendant thereto form a cycloalkyl, heterocyclyl, aryl or heteroaryl group; and

R ⁵ and R ⁶ are independently selected from hydrogen and -X ² R ¹⁰ ; wherein X ² is oxygen, and R ¹⁰ is aryl or substituted aryl.

In certain embodiments of the above methods,

^R2 is hydrogen or alkyl;

R ³ and R ⁴ are independently selected from hydrogen and -X ¹ R ⁸ ; wherein X ¹ is oxygen, and R ⁸ is aryl or substituted aryl; and

^R5 and ^R6 are hydrogen.

In certain embodiments of the above methods, R ¹¹ is C ₁ -C ₄ alkyl.

In certain embodiments of the above methods, R ¹¹ is methyl.

In certain embodiments of the above methods, R ¹² is C ₁ -C ₄ alkyl.

In certain embodiments of the above methods, R ¹² is methyl.

In certain embodiments of the methods disclosed above, the methods further comprise the step of forming a corresponding salt of the compound. Such methods are well known in the art.

Other modifications to obtain compounds of the present invention are well known to those skilled in the art. For example, a C-4 hydroxyl group can be converted to a corresponding ether, acyloxy group, or the like by conventional means to provide compounds of the present invention. Specifically, esters can be prepared by reacting a carboxylic acid-containing compound with an alcohol-containing compound in a suitable solvent, optionally at elevated temperature, under conventional coupling conditions. Thus, esters of the compounds disclosed herein can be formed at any carboxylic acid or hydroxyl functional group. Typical ester-forming reactions to provide compounds of the present invention are shown below, where ^R is as defined herein.

N-oxide derivatives of the above compounds can also be prepared using methods known to those skilled in the art. Therefore, the compounds of the present invention include N-oxide derivatives of the following formula:

Compounds of the present invention

In another aspect, the present invention relates to a compound of formula VIII, or a salt, ester, stereoisomer or stereoisomer mixture thereof:

in:

Z is O, NR ¹ or S;

^R1 is selected from hydrogen and alkyl;

^R2 is selected from hydrogen and alkyl, which is unsubstituted or substituted with one or more substituents independently selected from cycloalkyl, heterocyclyl, aryl and heteroaryl;

R ³ and R ⁴ are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ;

wherein X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, provided that when X ¹ is —SO or —SO ₂ —, then R ⁸ is not hydrogen; and

R ⁹ is selected from hydrogen, alkyl and aryl;

or R ³ and R ⁴ together with the carbon atoms pendant thereto form a cycloalkyl, substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl;

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl, and -X ² R ¹⁰ ;

wherein X ² is oxygen, -S(O) _n - or -NR ¹³ -;

n is 0, 1, or 2;

R ¹⁰ is selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl; and

R ¹³ is selected from hydrogen, alkyl and aryl;

or when X ² is —NR ¹³ —, then R ¹⁰ and R ¹³ together with the nitrogen atom to which they are attached may combine to form a heterocyclyl or substituted heterocyclyl group; and

R ⁷ is —N(R ¹¹ )(R ¹¹ ) or —OC(O)R ¹² ;

Each R ¹¹ is independently selected from an alkyl group, a benzyl group or an aryl group, or two R ^{11 s} together with the nitrogen atom to which they are attached form a 4-8 membered heterocyclic group or a heteroaryl group; and

R ¹² is selected from alkyl, aryl, heteroaryl and heterocyclyl;

with the proviso that the compound is not 1-dimethylaminomethyl-4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester.

In certain embodiments, the present invention relates to a compound of formula VIIIA, or a salt, ester, stereoisomer, or mixture of stereoisomers thereof:

in:

R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , n, X ¹ and X ² are as defined above in Formula VIII;

with the proviso that the compound is not 1-dimethylaminomethyl-4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester.

In certain embodiments of the above compounds, ^R2 is hydrogen, alkyl, or substituted alkyl.

In certain embodiments, ^R2 is alkyl.

In certain embodiments, R ³ and R ⁴ are independently selected from hydrogen, alkyl, cycloalkyl, aryl, heteroaryl, hydroxy, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ , and -X ¹ R ⁸ ; wherein

X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

^R8 is aryl or substituted aryl, and

R ⁹ is hydrogen, alkyl or aryl;

Alternatively, ^R3 and ^R4 together with the carbon atoms pendant thereto form a cycloalkyl, heterocyclyl, aryl or heteroaryl group.

In certain embodiments, R ⁵ and R ⁶ are hydrogen.

In certain embodiments, R ² is alkyl, which is unsubstituted or substituted with one or more substituents independently selected from cycloalkyl, heterocyclyl, aryl, and heteroaryl; and R ⁵ and R ⁶ are hydrogen.

In certain embodiments, R ⁷ is —OC(O)R ¹² . In certain embodiments, R ⁷ is —N(R ¹¹ )(R ¹¹ ). In certain embodiments, R ⁷ is —N(R ¹¹ )(R ¹¹ ); and R ¹¹ is C ₁ -C ₄ alkyl. In certain embodiments, R ⁷ is —OC(O)R ¹² ; and R ¹² is C ₁ -C ₄ alkyl.

In certain embodiments, Z is O.

In certain embodiments of the compounds disclosed herein above, each of R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁸ and R ¹⁰ is defined as follows:

R ³ and R ⁴ are independently selected from hydrogen, alkyl, cycloalkyl, heterocyclyl, aryl, heteroaryl, halogen, hydroxy, cyano, -S(O) _n -N(R ⁸ )-R ⁸ , -NR ⁸ C(O)NR ⁸ R ⁸ and -X ¹ R ⁸ ; wherein

X ¹ is oxygen, -S(O) _n - or -NR ⁹ -;

n is 0, 1, or 2;

Each R ⁸ is independently selected from hydrogen, alkyl, aryl, cycloalkyl, heteroaryl, and heterocyclyl; and

R ⁹ is selected from hydrogen, alkyl and aryl;

or R ³ and R ⁴ together with the carbon atoms pendant thereto form a cycloalkyl, heterocyclyl, aryl or heteroaryl group;

R ⁵ and R ⁶ are independently selected from hydrogen, halogen, alkyl, alkoxy, aryl, heteroaryl and -X ² R ¹⁰ ; wherein

X ² is oxygen, -S(O) _n - or -NR ¹³ -;

n is 0, 1, or 2;

R ¹⁰ is selected from alkyl, aryl, heteroaryl and heterocyclyl; and

R ¹³ is selected from hydrogen, alkyl and aryl;

or when X ² is -NR ¹³ -, then R ¹⁰ and R ¹³ together with the nitrogen atom to which they are attached may combine to form a heterocyclyl group;

wherein each of the above alkyl, alkoxy, cycloalkyl, heterocyclyl, aryl, heteroaryl and heterocyclyl groups may be optionally substituted with 1 to 3 R ¹⁰⁰ ,

wherein each R ¹⁰⁰ is independently selected from alkoxy, acyl, acylamino, acyloxy, amino, aminoacyl, aminocarbonylamino, aminothiocarbonylamino, aminocarbonyloxy, aryl, aryloxy, aryloxyaryl, cyano, halogen, hydroxy, nitro, oxo, thioxo, carboxyl, carboxyl ester, cycloalkyl, thio, alkylthio, arylthio, cycloalkylthio, heteroarylthio, heterocyclic heterocyclic thio, sulfonyl, heteroaryl, heterocyclic heterocyclic, cycloalkyloxy, heteroaryloxy, heterocyclic oxy, oxycarbonylamino, oxythiocarbonylamino, -OS(O) 2 -alkyl, -OS(O) ₂ -aryl, -OS(O) ₂ -heteroaryl, -OS(O) ₂ -heterocyclyl, -OSO ₂ -NR ⁴⁰ R ⁴⁰ , ^{-NR 40} _S (O) ₂ -NR ⁴⁰ -alkyl, -NR ⁴⁰ S(O) ₂ -NR ⁴⁰ -aryl, -NR ⁴⁰ S(O) ₂ -NR ⁴⁰ -heteroaryl, and -NR ⁴⁰ S(O) ₂ -NR ⁴⁰ -heterocyclyl, wherein each R ⁴⁰ is independently selected from hydrogen or alkyl;

with the proviso that the compound is not 1-dimethylaminomethyl-4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester.

In another aspect, the present invention relates to methyl 4-hydroxy-7-phenoxyisoquinoline-3-carboxylate (3a):

In another aspect, the present invention relates to methyl 4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxylate (3e):

Isoquinoline synthesis

The compounds and methods of the present invention can be used to synthesize various isoquinoline compounds. Such compounds are known to inhibit HIF hydroxylase activity, thereby increasing the stability and/or activity of hypoxia-inducible factor (HIF), and can be used to treat and prevent HIF-related conditions and disorders (see, for example, US Patent No. 7,323,475). Exemplary substituted isoquinoline compounds (which can be prepared using the methods disclosed herein) include those represented by Formula X and pharmaceutically acceptable salts, stereoisomers, stereoisomer mixtures, and esters thereof:

wherein R ³ , R ⁴ , R ⁵ and R ⁶ are as defined above in formula I, and:

When ^Ra is -COOH, p is 0; when ^Ra is -WR ¹⁸ , p is 1;

W is selected from oxygen, -S(O) _n- , and ^-NR19- , wherein n is 0, 1, or 2, ^R19 is selected from hydrogen, alkyl, substituted alkyl, acyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl, and ^R18 is selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclyl, and substituted heterocyclyl; or when W is ^-NR19- , then ^R18 and ^R19, together with the nitrogen atom to which they are attached, may combine to form a heterocyclyl or substituted heterocyclyl group;

R is selected from hydrogen, deuterium and methyl;

R' is selected from hydrogen, deuterium, alkyl and substituted alkyl; alternatively, R and R' and the carbon atoms pendant thereto may be combined to form a cycloalkyl, substituted cycloalkyl, heterocyclyl or substituted heterocyclyl group;

R" is selected from hydrogen and alkyl, or R" and R' together with the nitrogen pendant thereto may combine to form a heterocyclyl or substituted heterocyclyl group.

Exemplary methods for preparing compounds described herein are shown in the following schemes, wherein Z, ^X3 , R2, ^R3 , ^R4 , ^R5 , ^R6 , ^R11 , ^R12 , p, Ra, R, R ^' and R" are as defined above for Formula ^I and Formula X, and PG is a conventional amine protecting group.

Plan A

Compound A-200 used in the reaction shown in Scheme A can be prepared by contacting compound A-100 with a suitable Lewis acid, such as trimethyl borate, in the presence of a halogenating agent, such as dichlorotriphenylphosphorane and thionyl chloride, to produce an acid halide, which is then contacted with an alcohol of the formula R ² —OH, such as methanol, to produce the corresponding halogenated ester A-200. After completion of the reaction, A-200 can be recovered by conventional techniques, such as neutralization, extraction, precipitation, chromatography, filtration, etc., or alternatively, used in the next step without purification and/or isolation.

Compound A-200 can be converted to A-300 (Formula II) by contacting A-200 with an approximately stoichiometric amount of an appropriate α-amino acid of formula A-10 (wherein PG refers to a suitable protective group such as methylsulfonyl, p-toluenesulfonyl, etc.) and a catalytic amount of sodium iodide. The reaction is carried out under conventional coupling conditions well known in the art. A suitable base such as sodium methoxide, sodium ethoxide, or other suitable base in methanol, DMF, or other suitable solvent is then added. The reaction is carried out until it is substantially complete, which is typically carried out within about 1-72 hours. After completion of the reaction, the compound A-300 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, and the like.

Compound A-300 can be converted to B-100 (Formula I) by the method of the present invention as shown in Scheme B.

Plan B

For example, in the presence of an acid such as acetic acid, A-300 is contacted with an approximately stoichiometric amount or a slightly excessive amount of a compound of formula A-20 (Formula III) to provide compound B-100. The reaction proceeds until it is substantially complete, which typically occurs within about 1 to 72 hours. After completion of the reaction, compound B-100 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, or used in the next step without separation and/or purification.

Compound B-100 (Formula I) can be converted to compounds C-100 (Formula VII) and C-200 (Formula IV) by the process of the present invention as shown in Scheme C.

Plan C

For example, B-100 is contacted with an excess (e.g., 2-3 equivalents) of compound A-30 (Formula V) in the presence of an acid such as acetic acid to provide compounds C-100 and C-200. Alternatively, B-100 is contacted with an acyl halide of the formula R ¹² -C(O)X ³ or an alkyl halide of the formula R ¹² -X ³ , followed by contact with an acid of the formula R ¹² -C(O)OH, such as acetic acid, to provide compounds C-100 and C-200. The reaction is typically conducted at a temperature of approximately 100° C. and continued until substantially complete, which typically occurs within approximately 1-72 hours. Compound C-200 can be provided by the methods of the present invention, such as by reacting a mixture of compounds C-100 and C-200 with an amine such as morpholine in a suitable polar solvent such as DMF. The reaction is typically conducted at a temperature below room temperature (i.e., 0-10° C.). Once the reaction is complete, the compound C-200 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, and the like.

Under the reaction conditions of the present invention, compound C-200 (Formula IV) can be changed into C-300 (Formula VI). In certain embodiments, the reaction conditions are hydrogenation conditions. Such conditions generally include catalysts such as palladium catalysts (e.g., palladium (0) supported on carbon) under a hydrogen atmosphere. In some embodiments, the hydrogenation reaction is carried out under pressure. In some embodiments, the hydrogenation conditions include alkali such as sodium carbonate. In some embodiments, the hydrogenation conditions include about 0.5-about 1 molar equivalent of sodium carbonate.

Compound C-400 (Formula X) can be synthesized by contacting Compound C-300 (Formula VI) with at least a stoichiometric amount or a suitable excess of an amino acid or its derivative A-40 (specifically, but not limited to, glycine or its corresponding salt). The reaction is carried out under conventional coupling conditions well known in the art. In one embodiment, the reaction is carried out in the presence of sodium methoxide, sodium ethoxide, or another suitable base in methanol, DMF, or another suitable solvent at elevated reaction temperatures and particularly under reflux. The reaction continues until it is substantially complete, which is typically carried out within about 1-72 hours. Alternatively, the reaction can be carried out at high temperature in a microwave oven. Once the reaction is complete, Compound C-400 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, etc.

A specific method for preparing such substituted isoquinoline compounds is shown below in Scheme D, ^{wherein R2, R3, R4, R5, R11, R12 , p , Ra , R} , R' and R" are as defined herein, and PG is a conventional amine protecting group.

Plan D

Compound D-200 used in the reaction shown in Scheme D can be prepared by contacting compound A-100 with a suitable Lewis acid, such as trimethyl borate, in the presence of dichlorotriphenylphosphorane and thionyl chloride to produce an acid chloride, which, upon contact with an alcohol, such as methanol, produces the corresponding ester D-100. Once the reaction is complete, D-100 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, and the like; or alternatively, it can be used in the next step without purification and/or isolation.

Compound D-100 can be converted to D-200 (Formula IIA) by contacting D-100 with an approximately stoichiometric amount of an appropriate α-amino acid of Formula D-10 (where PG refers to a suitable protective group such as mesyl, tosyl, etc.) and a catalytic amount of sodium iodide. The reaction is carried out under conventional coupling conditions well known in the art. A suitable base such as sodium methoxide, sodium ethoxide, or another suitable base in methanol, DMF, or another suitable solvent is then added. The reaction is carried out until it is substantially complete, which is typically carried out within about 1-72 hours. Once the reaction is complete, the compound D-200 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, and the like.

Compound D-200 can be converted to D-300 (Formula IA) by the methods of the present invention. For example, D-200 is contacted with an approximately stoichiometric amount or a slightly excessive amount of a compound of Formula A-20 in the presence of an acid such as acetic acid to provide compound D-300. The reaction continues until it is substantially complete, which typically occurs within about 1-72 hours. Once the reaction is complete, the compound D-300 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, and the like.

Compound D-300 can be converted into compound D-400 (Formula VIIA) and D-500 (Formula IVA) by the method of the present invention. For example, in the presence of an acid such as acetic acid, D-300 is contacted with an excess (e.g., 2-3 equivalents) of compound A-30 to provide compounds D-400 and D-500. The reaction is typically carried out at a temperature of about 100°C and continued until it is substantially complete, which is typically carried out within about 1-72 hours. Compound D-500 can be provided by the method of the present invention, such as reacting a mixture of compounds D-400 and D-500 with an amine such as morpholine in a suitable polar solvent such as DMF. The reaction is typically carried out at a temperature below room temperature (e.g., 0-10°C). Once the reaction is complete, the compound D-500 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, and the like.

Compound D-500 can be changed into D-600 (Formula VIA) under the reaction conditions of the present invention. In certain embodiments, the reaction conditions are hydrogenation conditions. Such conditions generally include catalysts such as palladium catalysts (e.g., palladium (0) supported on carbon) under a hydrogen atmosphere. In some embodiments, the hydrogenation reaction is carried out under pressure. In some embodiments, the hydrogenation conditions include alkali such as sodium carbonate. In some embodiments, the hydrogenation conditions include about 0.5-about 1 molar equivalent of sodium carbonate.

Compound C-400 (Formula X) can be synthesized by contacting compound D-600 with at least a stoichiometric amount or an excess of a suitable amino acid or its derivative A-40 (specifically, but not limited to, glycine or its corresponding salt). The reaction is carried out under conventional coupling conditions well known in the art. In one embodiment, the reaction is carried out in the presence of sodium methoxide, sodium ethoxide, or another suitable base in methanol, DMF, or another suitable solvent at elevated reaction temperature and particularly under reflux. The reaction continues until it is substantially complete, which is typically carried out within about 1-72 hours. Alternatively, the reaction can be carried out at high temperature in a microwave oven. Once the reaction is complete, compound C-400 can be recovered by conventional techniques such as neutralization, extraction, precipitation, chromatography, filtration, etc.

Compound A-100, A-10, A-20, A-30, A-40 and D-10 used in the reaction described in the above scheme are available from commercial sources or can be prepared according to known literature procedures. Other variants of compound provided by the present invention are well known to those skilled in the art. For example, the C-4 hydroxyl can become corresponding ether, acyloxy etc. through conventional means. In addition, compound A-40 can be used as provided in US Patent No. 7323475.

In the art, isoquinoline compounds are prepared according to such methods, which are not desirable for large-scale production (Scheme E, wherein R ²⁰ is a general abbreviation representing a substituent as described herein (i.e., alkyl, alkoxy, aryl, aryloxy, etc.)). Exemplary substituents include alkyl, alkoxy, heteroalkyl, aryl, aryloxy, etc., each of which is as defined herein. For example, isoquinoline compounds prepared according to US Patent No. 7,323,475 include undesirable regioisomers E-200 and E-300, which are chromatographically separated. It is expected that such a method will be inefficient on a large scale. In addition, the conversion of E-400 to the corresponding bromide E-500 to provide the alkyl substitution on the isoquinoline ring of compound E-600 requires the use of phosphorus oxybromide, which is toxic and potentially explosive. In contrast to previously disclosed methods, the method of the present invention has the advantage that such hazardous reagents do not need to be used to synthesize isoquinoline compounds.

Plan E

The synthesis of 1-dimethylaminomethyl-4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester has been reported in U.S. Patent No. 7,323,475, which used a mixture of 4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester, N,N-dimethylmethyleneammonium iodide, and potassium carbonate in anhydrous dichloromethane. However, only 16% of the desired 1-dimethylaminomethyl-4-hydroxy-7-phenylsulfanyl-isoquinoline-3-carboxylic acid butyl ester was obtained. In contrast to previously disclosed methods, the present method has the advantage of providing good yields for the compounds described herein.

Example

The present invention will be further understood by reference to the following examples, which are intended to be purely illustrative of the present invention. The present invention is not limited in scope to the exemplary embodiments, which are intended to illustrate individual aspects of the present invention only. Any functionally equivalent methods are within the scope of the present invention. Various modifications of the present invention, in addition to those described herein, will become apparent to those skilled in the art from the foregoing description and accompanying drawings. Such modifications fall within the scope of the appended claims.

Unless otherwise indicated, all temperatures are in degrees Celsius (° C.). Also, in these examples and elsewhere, the abbreviations have the following meanings:

EtOH = ethanol

Et = Ethyl

g = grams

h = hours

HPLC = High Performance Liquid Chromatography

L = liters

MeOH = methanol

mg = milligrams

min = minutes

mL = milliliters

mM = millimolar

mmol = millimole

Ac＝Acetyl

NaOMe = sodium methoxide

Example 1

Preparation of 2-(4-hydroxy-1-methyl-5-phenoxyisoquinoline-3-carboxamido)acetic acid

a) Preparation of methyl 1-((dimethylamino)methyl)-4-hydroxy-5-phenoxyisoquinoline-3-carboxylate (1b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 1a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 1a in acetic acid can be stirred vigorously with a magnetic stirrer (Note: For larger-scale processes, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55±5°C and maintained for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 1a is greater than 0.5%, the reaction can be stirred at 55±5°C for an additional 2 hours and evaluated again by HPLC.

b) Preparation of methyl 1-((acetoxy)methyl)-4-hydroxy-5-phenoxyisoquinoline-3-carboxylate (1c)

The 1b solution from Example 1a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a temperature rise of 20-25°C can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and the dimethylamine of 1b. Excessive heat generated will result in the unsafe rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 1b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

1d can be converted to 1c by the following procedure. The solution of 1c and 1d from the above procedure can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered and the wet cake washed with water (3X) and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer), and the solution can be evaluated by HPLC.

1c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 1d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 1c will precipitate from the cold acetone/methanol solution, which can be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of methyl 4-hydroxy-1-methyl-5-phenoxyisoquinoline-3-carboxylate (1e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 1c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum purged with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (1c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace purged three times with nitrogen, and filtered through glass microfiltration filter paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-(4-hydroxy-1-methyl-5-phenoxyisoquinoline-3-carboxamido)acetic acid (1f)

2-(4-Hydroxy-1-methyl-5-phenoxyisoquinoline-3-carboxamido)acetic acid can be prepared from 1e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 1e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (having 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 hours, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can be continued until less than 1% of 1e remains when measured by HPLC, filtered, washed with methanol, vacuum dried, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. The ethyl acetate can be removed, and an acetic acid solution (having 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, and the solid washed with water (3X), cold acetone (5-10° C., 2X), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10° C., 3X), and dried under vacuum to obtain 2-(4-hydroxy-1-methyl-5-phenoxyisoquinoline-3-carboxamido)acetic acid.

Example 2

Preparation of 2-(4-hydroxy-1-methyl-6-phenoxyisoquinoline-3-carboxamido)acetic acid

a) Preparation of methyl 1-((dimethylamino)methyl)-4-hydroxy-6-phenoxyisoquinoline-3-carboxylate (2b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 2a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 2a in acetic acid can be vigorously stirred with a magnetic stirrer (Note: For larger-scale processing, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55±5°C and maintained for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 2a is greater than 0.5%, the reaction can be stirred at 55±5°C for 2 hours and evaluated again by HPLC.

b) Preparation of methyl 1-((acetoxy)methyl)-4-hydroxy-6-phenoxyisoquinoline-3-carboxylate (2c)

The solution of 2b from Example 2a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a 20-25°C temperature rise can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and dimethylamine or 2b. Excess heat generated will result in the unsafe rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 2b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

2d can be converted to 2c by the following steps. The solution of 2c and 2d from the above step can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered and the wet cake washed with water (3X) and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer) and the solution evaluated by HPLC.

2c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 2d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 2c will precipitate from the cold acetone/methanol solution, which can be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of methyl 4-hydroxy-1-methyl-6-phenoxyisoquinoline-3-carboxylate (2e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 2c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum purged with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (2c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace purged three times with nitrogen, and filtered through glass microfiltration filter paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-(4-hydroxy-1-methyl-6-phenoxyisoquinoline-3-carboxamido)acetic acid (2f)

2-(4-Hydroxy-1-methyl-6-phenoxyisoquinoline-3-carboxamido)acetic acid was prepared from 2e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 2e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (with 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 h, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can continue until less than 1% of 2e remains when measured by HPLC, which is then filtered, washed with methanol, vacuum-dried, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. Ethyl acetate can be removed, and acetic acid solution (with 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, and the solid washed with water (3×), cold acetone (5-10° C., 2×), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10° C., 3X) and dried under vacuum to obtain 2-(4-hydroxy-1-methyl-6-phenoxyisoquinoline-3-carboxamido)acetic acid.

Example 3

Preparation of 2-(4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxamido)acetic acid

a) Preparation of 5-phenoxybenzofuranone

DMF (68Kg) is loaded into the reactor and stirring is started. The reactor is then charged with phenol (51Kg), acetylacetone (8Kg), 5-bromobenzofuranone (85Kg), cupric bromide (9Kg) and potassium carbonate (77Kg). The mixture is heated to above 85°C and maintained until the reaction is complete, then cooled. Water is added. The solid is filtered and washed with water. The solid is dissolved in dichloromethane and washed with an HCl aqueous solution and then washed with water. The solvent is removed under pressure and methanol is added. The mixture is stirred and filtered. The solid is washed with methanol and dried in a stove to produce 5-phenoxybenzofuranone (yield: 72%, HPLC: 99.6%).

b) Preparation of methyl 2-chloromethyl-4-phenoxybenzoate

Toluene (24Kg) was loaded into the reactor and stirring was started. 5-phenoxybenzofuranone (56Kg), thionyl chloride (41Kg), trimethyl borate (1Kg), dichlorotriphenylphosphorane (2.5Kg) and potassium carbonate (77Kg) were then loaded into the reactor. The mixture was heated to reflux until the reaction was complete, and the solvent was removed to leave 2-chloromethyl-4-phenoxybenzoyl chloride. Methanol was added and the mixture was heated to above 50°C until the reaction was complete. The solvent was removed and replaced with DMF. The solution of the product, methyl 2-chloromethyl-4-phenoxybenzoate in DMF, was directly used in the next step (HPLC: 85%).

c) Preparation of methyl 4-hydroxy-7-phenoxyisoquinoline-3-carboxylate (3a)

A solution of methyl 2-chloromethyl-4-phenoxybenzoate (~68 Kg) in DMF was charged to a reactor and stirring was started. The reactor was then charged with methyl p-toluenesulfonylglycine ester (66 Kg), potassium carbonate (60 Kg) and sodium iodide (4 Kg). The mixture was heated to at least 50°C until the reaction was complete. The mixture was cooled. A solution of sodium methoxide in methanol was charged and the mixture was stirred until the reaction was complete. Acetic acid and water were added and the mixture was stirred, filtered and washed with water. The solid was purified by trituration with acetone and dried in an oven to give 3a (yield from step b): 58%; HPLC: 99.4%). ¹ H NMR (200 MHz, DMSO-d6) d 11.60 (s, 1H), 8.74 (s, 1H), 8.32 (d, J = 9.0 Hz, 1H), 7.60 (dd, J = 2.3 & 9.0 Hz, 1H), 7.49 (m, 3H), 7.24 (m, 3H), 3.96 (s, 3H); MS-(+)-ion M+1 = 296.09

d) Preparation of methyl 1-((dimethylamino)methyl)-4-hydroxy-7-phenoxyisoquinoline-3-carboxylate (3b)

A flask was charged with 3a (29.5 g) and acetic acid (44.3 g ± 5%), and stirred. Bis-dimethylaminomethane (12.8 g ± 2%) was slowly added. The mixture was heated to 55 ± 5°C and maintained until the reaction was complete. The reaction product was evaluated by MS, HPLC, and ^H NMR. ^H NMR (200 MHz, DMSO-d6) d 11.7 (s, 1H), 8.38 (d, J = 9.0 Hz, 1H), 7.61 (dd, J = 9.0, 2.7 Hz, 1H), 7.49 (m, 3H), 7.21 (m, 3H), 5.34 (s, 2H), 3.97 (s, 3H), 1.98 (s, 3H); MS-(+)-ion M+1 = 368.12.

e) Preparation of methyl 1-((acetoxy)methyl)-4-hydroxy-7-phenoxyisoquinoline-3-carboxylate (3c)

The solution of 3b from a) above was cooled to below 25° C., at which point acetic anhydride (28.6 g ± 3.5%) was added to maintain the temperature below 50° C. The resulting mixture was heated to 100 ± 5° C. until the reaction was complete.

The solution of 3c and 3d above was cooled to less than 65 ± 5 ° C. Water (250 mL) was slowly added. The mixture was then cooled to less than 20 ± 5 ° C and filtered. The wet cake was washed with water (3x50 mL) and added to a new flask. Dichloromethane (90 mL) and water (30 mL) were added and the resulting mixture was stirred. The dichloromethane layer was separated and evaluated by HPLC.

The organic layer was added to a flask and cooled to 5±5°C. Morpholine was added and the mixture was stirred until the reaction was complete. The solvent was replaced with an acetone/methanol mixture. After cooling, compound 3c precipitated and was filtered, washed, and dried in an oven (yield: 81%, HPLC: >99.7%). ^1H NMR (200 MHz, DMSO-d6) d 11.6 (s, 1H), 8.31 (d, J=9.0 Hz, 1H), 7.87 (d, J=2.3 Hz, 1H), 7.49 (m, 3H), 7.24 (m, 3H), 3.95 (s, 3H), 3.68 (s, 2H), 2.08 (s, 6H); MS-(+)-ion M+1=357.17.

f) Preparation of methyl 4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxylate (3e)

A reactor was charged with 3c (16.0 g), Pd/C (2.08 g), anhydrous _{Na₂CO₃ (} 2.56 g), and ethyl acetate (120 mL). The flask was vacuum purged with nitrogen (3X) and hydrogen (3X). The flask was then pressurized with hydrogen and stirred at approximately 60°C until the reaction was complete. The flask was cooled to 20-25°C, the pressure was released to ambient, the headspace was purged three times with nitrogen, and the mixture was filtered. The filtrate was concentrated. Methanol was added. The mixture was stirred and then cooled. The product precipitated, filtered, and dried in an oven (yield: 90%, HPLC: 99.7%).

g) Preparation of 2-(4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxamido)acetic acid (3f)

2-(4-Hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxamido)acetic acid was prepared from 3e according to the following procedure.

A pressure flask was charged with 3e (30.92 g), glycine (22.52 g), methanol (155 mL), sodium methoxide solution (64.81 g), and sealed (as an option, sodium glycinate was used instead of glycine and sodium methoxide). The reaction was heated to approximately 110° C. until the reaction was complete. The mixture was cooled, filtered, washed with methanol, dried under vacuum, dissolved in water, and washed with ethyl acetate. The ethyl acetate was removed, and acetic acid (18.0 g) solution was added to the resulting aqueous layer. The suspension was stirred at room temperature, filtered, and the solid was washed with water (3×30 mL), cold acetone (5-10° C., 2×20 mL), and dried under vacuum to obtain 2-(4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxamido)acetic acid (yield: 86.1%, HPLC: 99.8%).

Example 4

Preparation of 2-(4-hydroxy-1-methyl-8-phenoxyisoquinoline-3-carboxamido)acetic acid

a) Preparation of methyl 1-((dimethylamino)methyl)-4-hydroxy-8-phenoxyisoquinoline-3-carboxylate (4b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 4a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 4a in acetic acid can be vigorously stirred with a magnetic stirrer (Note: For larger-scale processes, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55±5°C and maintained for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 4a is greater than 0.5%, the reaction can be stirred at 55±5°C for an additional 2 hours and evaluated again by HPLC.

b) Preparation of methyl 1-((acetoxy)methyl)-4-hydroxy-8-phenoxyisoquinoline-3-carboxylate (4c)

The solution of 4b from Example 4a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a 20-25°C temperature rise can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and dimethylamine 4b. Excessive heat generated would result in the unsafe rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 4b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

4d can be converted to 4c by the following steps. The solution of 4c and 4d from the above step can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered and the wet cake washed (3X) with water and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer) and the solution evaluated by HPLC.

4c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 4d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 4c will precipitate from the cold acetone/methanol solution, which can be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of 4-hydroxy-1-methyl-8-phenoxyisoquinoline-3-carboxylic acid methyl ester (4e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 4c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum purged with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (4c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace purged three times with nitrogen, and filtered through glass microfiltration filter paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-(4-hydroxy-1-methyl-8-phenoxyisoquinoline-3-carboxamido)acetic acid (4f)

2-(4-Hydroxy-1-methyl-8-phenoxyisoquinoline-3-carboxamido)acetic acid was prepared from 4e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 4e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (having 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 h, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can continue until less than 1% of 4e remains when measured by HPLC, which is then filtered, washed with methanol, dried under vacuum, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. Ethyl acetate can be removed, and acetic acid solution (having 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, and the solid washed with water (3X), cold acetone (5-10° C., 2X), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10° C., 3X) and dried under vacuum to obtain 2-(4-hydroxy-1-methyl-8-phenoxyisoquinoline-3-carboxamido)acetic acid.

Example 5

Preparation of 2-[4-hydroxy-1-methyl-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid

a) Preparation of 1-((dimethylamino)methyl)-4-hydroxy-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (5b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 5a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 5a in acetic acid can be stirred vigorously with a magnetic stirrer (Note: For larger-scale processes, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55 ± 5°C and maintained for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 5a is greater than 0.5%, the reaction can be stirred at 55 ± 5°C for an additional 2 hours and evaluated again by HPLC.

b) Preparation of 1-((acetoxy)methyl)-4-hydroxy-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (5c)

The solution of 5b from Example 5a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a 20-25°C temperature rise can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and dimethylamine or 5b. Excess heat generated will result in the unsafe rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 5b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

5d can be converted to 5c by the following steps. The solution of 5c and 5d from the above step can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered and the wet cake washed (3X) with water and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer) and the solution evaluated by HPLC.

5c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 5d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 5c will precipitate from the cold acetone/methanol solution, which can be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of 4-hydroxy-1-methyl-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (5e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 5c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum carboxylated with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (5c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace carboxylated three times with nitrogen, and filtered through glass microfiltration paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-[4-hydroxy-1-methyl-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid (5f)

2-[4-Hydroxy-1-methyl-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid was prepared from 5e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 5e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (having 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 h, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can continue until less than 1% of 5e remains when measured by HPLC, which is then filtered, washed with methanol, vacuum dried, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. Ethyl acetate can be removed, and acetic acid solution (having 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, the solid washed with water (3X), cold acetone (5-10° C., 2X), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10° C., 3X), and dried under vacuum to obtain 2-[4-hydroxy-1-methyl-7-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid.

Example 6

Preparation of 2-[4-hydroxy-1-methyl-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid

a) Preparation of 1-((dimethylamino)methyl)-4-hydroxy-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (6b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 6a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 6a in acetic acid can be vigorously stirred with a magnetic stirrer (Note: For larger-scale processes, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55±5°C for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 6a is greater than 0.5%, the reaction can be stirred at 55±5°C for an additional 2 hours and evaluated again by HPLC.

b) Preparation of 1-((acetoxy)methyl)-4-hydroxy-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (6c)

The solution of 6b from Example 6a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a temperature rise of 20-25°C can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and dimethylamine or 6b. Excessive heat generated will result in the unsafe rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 6b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

6d can be converted to 6c by the following steps. The solution of 6c and 6d from the above step can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered and the wet cake washed with water (3X) and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer) and the solution evaluated by HPLC.

6c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 6d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 6c will precipitate from the cold acetone/methanol solution, be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of 4-hydroxy-1-methyl-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (6e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 6c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum purged with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (6c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace purged three times with nitrogen, and filtered through glass microfiltration paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-[4-hydroxy-1-methyl-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid (6f)

2-[4-Hydroxy-1-methyl-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid was prepared from 6e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 6e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (having 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 h, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can continue until less than 1% of 6e remains when measured by HPLC, filtered, washed with methanol, vacuum dried, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. Ethyl acetate can be removed, and acetic acid solution (having 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, and the solid washed with water (3X), cold acetone (5-10° C., 2X), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10° C., 3X), and dried under vacuum to obtain 2-[4-hydroxy-1-methyl-6-(4-methoxy-phenoxy)-isoquinoline-3-carboxamido]acetic acid.

Example 7

Preparation of 2-[4-hydroxy-1-methyl-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid

a) Preparation of 1-((dimethylamino)methyl)-4-hydroxy-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (7b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 7a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 7a in acetic acid can be vigorously stirred with a magnetic stirrer (Note: For larger-scale processes, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55±5°C and maintained for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 7a is greater than 0.5%, the reaction can be stirred at 55±5°C for an additional 2 hours and evaluated again by HPLC.

b) Preparation of 1-((acetoxy)methyl)-4-hydroxy-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (7c)

The solution of 7b from Example 7a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a 20-25°C temperature rise can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and dimethylamine or 7b. Excess heat generated will result in an unsafe and rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 7b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

7d can be converted to 7c by the following steps. The solution of 7c and 7d from the above step can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered, the wet cake washed with water (3X) and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer) and the solution evaluated by HPLC.

7c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 7d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 7c will precipitate from the cold acetone/methanol solution, which can be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of 4-hydroxy-1-methyl-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (7e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 7c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum purged with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (7c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace purged three times with nitrogen, and filtered through glass microfiltration paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-[4-hydroxy-1-methyl-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid (7f)

2-[4-Hydroxy-1-methyl-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid was prepared from 7e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 7e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (having 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 h, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can continue until less than 1% of 7e remains when measured by HPLC, which is then filtered, washed with methanol, dried under vacuum, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. Ethyl acetate can be removed, and acetic acid solution (having 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, and the solid washed with water (3×), cold acetone (5-10° C., 2×), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10 ° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10 ° C., 3X), and dried under vacuum to obtain 2-[4-hydroxy-1-methyl-7-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid.

Example 8

Preparation of 2-[4-hydroxy-1-methyl-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid

a) Preparation of 1-((dimethylamino)methyl)-4-hydroxy-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (8b)

A round-bottom flask equipped with a thermocouple and a condenser can be charged with 8a and acetic acid (approximately 7 molar equivalents ± 5%). The suspension of 8a in acetic acid can be vigorously stirred with a magnetic stirrer (Note: For larger-scale processes, overhead stirring should be performed). A slight excess of bis-dimethylaminomethane (approximately 1.25 molar equivalents) can then be slowly added to the mixture [Note: The reaction is slightly exothermic and a temperature rise of 15-20°C can be observed]. After the addition is complete, the mixture can be heated to 55±5°C and maintained for at least 8 hours. The reaction can then be evaluated by HPLC. If the amount of 8a is greater than 0.5%, the reaction can be stirred at 55±5°C for an additional 2 hours and evaluated again by HPLC.

b) Preparation of 1-((acetoxy)methyl)-4-hydroxy-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (8c)

The solution of 8b from Example 8a) can be cooled to below 25°C, at which point acetic anhydride (approximately 3 molar equivalents) at a temperature below 50°C can be slowly added [Note: The reaction is exothermic and a 20-25°C temperature rise can be observed. The rate of addition is important for controlling the exothermic reaction between acetic anhydride and dimethylamine or 8b. Excess heat generated will result in the unsafe rapid formation of gaseous dimethylamine]. After the addition is complete, the mixture can be heated to 100±5°C for 20-24 hours. The reaction can then be evaluated by HPLC. If the amount of 8b is greater than 2%, the reaction can be stirred for an additional 2 hours and then evaluated again by HPLC.

8d can be converted to 8c by the following steps. The solution of 8c and 8d from the above step can be cooled to less than 65±5°C and mixed well. If the reaction temperature is below 30°C, the reaction will solidify. Water can be added slowly and steadily (the first half can be added after 1 hour and the rest after 30 minutes). The mixture can then be cooled and stirred at 20±5°C for at least 3 hours, at which time the mixture can be filtered, the wet cake washed with water (3X) and added to a round-bottom flask equipped with a mechanical stirrer. Dichloromethane and water (3:1 volume) can be added and the mixture stirred for 30 minutes. The dichloromethane can be separated (excluding the interface or aqueous layer) and the solution evaluated by HPLC.

8c can be further purified according to the following procedure. The above solution can be added to a flask equipped with a mechanical stirrer and cooled to 5±5°C. Morpholine can be added, and the mixture can be stirred at 5±5°C for 30-60 minutes and evaluated by HPLC. If the amount of 8d is greater than 2%, the reaction can be stirred for an additional hour. Once the reaction is complete, 8c will precipitate from the cold acetone/methanol solution, be filtered, washed, and dried under vacuum at 50±5°C.

c) Preparation of 4-hydroxy-1-methyl-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxylic acid methyl ester (8e)

A glass-lined Parr pressure reactor vessel equipped with a 4-blade impeller can be charged with 8c, Pd/C (approximately 0.4-0.5 molar equivalents), _{anhydrous Na2CO3} (approximately 0.5 molar equivalents), and ethyl acetate. The flask can then be vacuum purged with nitrogen (3X) and vacuum purged with hydrogen (3X). The flask can then be pressurized with hydrogen to a set point of 60 psi and stirred at 60°C for 6-8 hours until the reaction is complete (8c <0.5%). The flask can then be cooled to 20-25°C, the pressure released to ambient, the headspace purged three times with nitrogen, and filtered through glass microfiltration paper. The filtrate can be concentrated and precipitated from cold methanol and dried under vacuum at 50±5°C.

d) Preparation of 2-[4-hydroxy-1-methyl-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid (8f)

2-[4-Hydroxy-1-methyl-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid was prepared from 8e according to the following procedure.

A pressure glass reaction flask (which includes a top thread for a screw cap) can be equipped with a magnetic stirrer, charged with 8e, glycine (approximately 3 molar equivalents), methanol, and sodium methoxide solution (having 1.2 molar equivalents of NaOCH ₃ ), and sealed. The reaction can then be heated to 110° C. for at least 6 h, during which time the reaction forms a yellow suspension. The reaction can then be cooled to 20-25° C. and evaluated by HPLC. The reaction can continue until less than 1% of 8e remains when measured by HPLC, filtered, washed with methanol, vacuum dried, dissolved in water, and extracted with ethyl acetate to remove impurities to less than 0.1%. Ethyl acetate can be removed, and acetic acid solution (having 3 molar equivalents of acetic acid) can be added after 1 hour. The suspension can be stirred at room temperature for at least 3 hours, filtered, the solid washed with water (3X), cold acetone (5-10° C., 2X), and evaluated for impurities by HPLC. If acetone-removable impurities are present, the flask can be charged with acetone and refluxed for at least 8 h, slowly cooled to 5-10° C., stirred for at least 2-3 h, filtered, washed with cold acetone (5-10° C., 3X), and dried under vacuum to obtain 2-[4-hydroxy-1-methyl-6-(3,5-difluoro-phenoxy)-isoquinoline-3-carboxamido]acetic acid.

Example 9

Biological tests

The compounds and methods of the present invention can be used to synthesize various isoquinoline compounds. Such compounds are known to inhibit HIF hydroxylase activity, thereby increasing the stability and/or activity of hypoxia-inducible factor (HIF), and to treat and prevent HIF-related conditions and disorders (see, for example, US Patent No. 7,323,475, US Publication No. 2007/0004627, US Publication No. 2006/0276477, and US Publication No. 2007/0259960, which are incorporated herein by reference).

The biological activity of the exemplary substituted isoquinoline compounds can be evaluated using any conventionally known method. In a specific embodiment, cells derived from animal tissue (preferably human tissue) that are capable of expressing erythropoietin when stimulated by a compound of the invention are cultured for in vitro production of endogenous proteins. Cells contemplated for use in this method include, but are not limited to, cells derived from liver, hematopoietic, renal, and nervous system tissues.

Cell culture techniques are generally available in the art and include any method that can maintain cell viability and promote the expression of endogenous proteins. Cells are typically cultured in a growth medium optimized for cell growth, survival, and protein production. Cells can be in suspension or attached to a matrix, and the culture medium can be supplied in the form of batch feed or continuous flow. The compound of the present invention is added to the culture medium at a level that stimulates the production of erythropoietin without compromising the level of cell viability. The erythropoietin produced by the cells is secreted into the culture medium. The culture medium is then collected and the erythropoietin is purified using methods known to those skilled in the art. (See, for example, Lai et al. (1987) US Patent No. 4,667,016; and Egrie (1985) US Patent No. 4,558,006).

Suitable detection methods are well known in the art. The following are merely provided as examples and are not intended to limit the present invention.

Cell-based HIFα stability assay

Human cells derived from various tissues (e.g., Hep3B cells from hepatocyte tissue) were seeded into 35 mm culture dishes and _cultured in a standard culture medium, such as Dulbecco's Modified Eagle's Medium (DMEM), containing 10% FBS (fetal bovine serum), at 37°C, 20% _O₂ , and 5% CO₂. When the cell layer reached confluence, the culture medium was replaced with OPTI-MEM (Invitrogen Life Technologies, Carlsbad, CA), and the cell layer was cultured at 37°C, 20% _O₂ , and 5% _CO₂ for approximately 24 hours. The compound or 0.013% DMSO (dimethyl sulfoxide) was then added to the culture medium, and the culture was continued overnight.

After cultivation, the culture medium is removed, centrifuged and stored for analysis (see below based on cell VEGF and EPO detection). The cells are washed twice with cold phosphate buffered saline (PBS), then lysed on ice for 15 minutes in 1mL of 10mMTris (pH7.4), 1mM EDTA, 150mM NaCl, 0.5%IGEPAL (Sigma-Aldrich, St.Louis MO) and a protease inhibitor cocktail (Roche Molecular Biochemicals). The cell lysate is centrifuged at 3000 × g and 4°C for 5 minutes, and the cytosol fraction (supernatant) is collected. The core (pellet) is resuspended, and the cells are dissolved in 100 μL of 20mM HEPES (pH7.2), 400mM NaCl, 1mM EDTA, 1mM dithiothreitol and a protease cocktail (Roche Molecular Biochemicals), centrifuged at 13000 × g and 4°C for 5 minutes, and the nuclear protein fraction (supernatant) is collected.

The collected nuclear protein fractions were analyzed for HIF-1α using the QUANTIKINE immunoassay (R&D Systems, Inc., Minneapolis, MN) according to the manufacturer's instructions.

Cell-based EPO assays

Hep3B cells (human hepatocellular carcinoma cells, from ATCC, cat# HB-8064) were seeded into 96-well plates at 25,000 cells/well. The next day, the cells were washed once with DMEM (Cellgro, cat# 10-013-CM) + 0.5% calf serum (Cellgro, cat# 35-010-CV) and cultured for 72 hours in DMEM + 0.5% calf serum with various concentrations of compound or vehicle control (0.15% DMSO). Cell-free culture supernatants were generated by transfer to conical-bottomed 96-well plates and centrifugation at 2000 rpm for 5 minutes. The supernatants were quantified for EPO using a human EPO ELISA kit (R&D Systems, cat# DEP00).

The EPO values of the compounds reported herein (e.g., Table 1) are cell measurements minus the solvent control values of the same cell preparations for the compound measurements. The solvent control EPO values of the cell preparations used in the experiments reported herein vary from 0 to 12.5 mIU/ml.

HIF-PH detection

Ketoglutarate α-[1- ¹⁴ C]-sodium salt, α-ketoglutarate sodium salt, and HPLC-purified peptides were obtained from commercial sources, such as Perkin-Elmer (Wellesley, MA), Sigma-Aldrich, and SynPep Corp. (Dublin, CA), respectively. The peptides used in the assays were fragments of HIFα described above or disclosed in International Publication No. WO 2005/118836, which is incorporated herein by reference. For example, the HIF peptide used in the HIF-PH assay was [methoxycoumarin]-DLDLEALAPYIPADDDFQL-amide. HIF-PH, such as HIF-PH2 (also known as EGLN1 or PHD2), was expressed in, for example, insect Hi5 cells and partially purified, for example, by SP ion exchange chromatography. Enzyme activity was determined by capturing ¹⁴ _CO2 using the assay described by Kivirikko and Myllyla (1982, Methods Enzymol. 82:245-304). The assay reaction contained 50 mM HEPES (pH 7.4), 100 μM α-ketoglutarate sodium salt, 0.30 μCi/mL α-ketoglutarate α-[1- ¹⁴ C]-sodium salt, 40 μM FeSO ₄ , 1 mM ascorbate, 1541.8 units/mL of catalase, with or without 50 μM peptide substrate and various concentrations of the compound of the invention. The reaction was initiated by the addition of HIF-PH enzyme.

Peptide-associated percent turnover was calculated by subtracting the percent turnover in the absence of the peptide from the percent turnover in the presence of the matrix peptide. Percent inhibition and _IC50 were calculated using the peptide-associated percent turnover at a given inhibitor concentration. _IC50 values for each inhibitor were calculated using GraFit software (Erithacus Software Ltd., Surrey, UK). The results are summarized in Table 1.

The following Table 1 is intended to demonstrate the pharmacological utility of exemplary substituted isoquinoline compounds. By inhibiting HIF prolyl hydroxylases, the substituted isoquinoline compounds stabilize HIFα, which then binds to HIFβ to form an active transcription factor that increases the expression of numerous genes involved in responding to hypoxic and ischemic conditions, including erythropoietin (EPO).

Table 1

*Cellular EPO measured at 30 μM compound in DMSO compared to DMSO only control.

Claims (90)

1. A method for preparing a compound of formula I, This includes contacting a compound of formula II with a compound of formula III under reaction conditions sufficient to produce a compound of formula I: in Z is O, NR ¹ , or S; ^R1 is selected from hydrogen and alkyl groups; R ² is selected from hydrogen and unsubstituted alkyl groups or substituted with one or more substituents independently selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , ^-NR8C ( ^{O ) NR8R8} and ^-X1R8 ; Where ^X1 is oxygen, -S(O) _n- or ^-NR9- ; n is 0, 1, or 2; Each ^R8 is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic, provided that ^R8 is not hydrogen when ^X1 is –SO- or _–SO2- ; and R ⁹ is selected from hydrogen, alkyl, and aryl; Alternatively, ^R3 and ^R4 together with the carbon atoms attached to them can form cycloalkyl, substituted cycloalkyl, heterocycloyl, substituted heterocycloyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl. ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^{–X2R10 ;} Where X ² is oxygen, -S(O) _n- or –NR ^13- ; n is 0, 1, or 2; R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic; and R ¹³ is selected from hydrogen, alkyl, and aryl; Alternatively, when ^X2 is –NR ^13- , ^R10 and ^R13 , together with the nitrogen atoms bonded to them, can combine to form heterocyclic groups or substituted heterocyclic groups; and Each R ¹¹ is independently selected from alkyl, benzyl, or aryl, or two R ¹¹ together with the nitrogen atom to which they are attached form a 4-8 membered heterocyclic or heteroaryl group. 2. Methods for preparing compounds of formula IA: This includes contacting a compound of formula IIA with a compound of formula III under reaction conditions sufficient to produce a compound of formula IA: in R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR13- , wherein n is ⁰ , 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom bonded to them can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic; and Each R ¹¹ is independently selected from alkyl, benzyl, or aryl, or two R ¹¹ together with the nitrogen atom to which they are attached form a 4-8 membered heterocyclic or heteroaryl group. 3. The method of claim 1 or 2, wherein the reaction conditions include an acid. 4. The method of claim 3, wherein the acid is glacial acetic acid. 5. The method of claim 1 or 2, wherein the reaction is carried out at a temperature greater than 30°C. 6. The method of claim 1 or 2, wherein the reaction is carried out at a temperature of 50°C-60°C. 7. The method of claim 1 or 2, wherein R ¹¹ is a _C1 - _C4 alkyl group. 8. Methods for preparing compounds of formula IV: It includes reacting a compound of formula I under reaction conditions sufficient to produce a compound of formula IV: Contact with compounds of formula ^R12 -X3, followed by contact with compounds of formula R12- ^X3 ; or contact with compounds of formula V: in Z is O, NR ¹ , or S; ^R1 is selected from hydrogen and alkyl groups; R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR13- , wherein n is ⁰ , 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom bonded to them can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic; Each R ¹¹ is independently selected from alkyl, benzyl or aryl, or two R ¹¹ together with the nitrogen atom attached to them form a 4-8 membered heterocyclic group or heteroaryl group; Each R ¹² is independently selected from alkyl, aryl, heteroaryl, and heterocyclic groups, or when two R ^12s are present, the two R ^12s together with the carbon atoms attached to them form a 4-8 membered heterocyclic group; and ^X3 is a halogen. 9. Methods for preparing compounds of formula IVA: This includes contacting a compound of formula IA with a compound of formula V under reaction conditions sufficient to produce a compound of formula IVA: in R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR13- , wherein n is ⁰ , 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom to which they are attached can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic; Each R ¹¹ is independently selected from alkyl, benzyl, or aryl, or two R ^11s together with the nitrogen atom attached to them form a 4-8 membered heterocyclic or heteroaryl group; and Each R ¹² is independently selected from alkyl, aryl, heteroaryl, and heterocyclic groups, or two R ^12s together with the carbon atoms attached to them form a 4-8 membered heterocyclic group. 10. The method of claim 8 or 9, wherein the reaction conditions comprise compounds of formula V. 11. The method of claim 8 or 9, wherein the reaction is carried out under an inert atmosphere. 12. The method of claim 8 or 9, wherein the reaction is carried out under a nitrogen atmosphere. 13. The method of claim 8 or 9, wherein the reaction conditions are anhydrous reaction conditions. 14. The method of claim 8 or 9, wherein the reaction is carried out at a temperature greater than 30°C. 15. The method of claim 8 or 9, wherein the reaction is carried out at a temperature of about 100°C. 16. The method of claim 8 or 9, wherein ^R11 and ^R12 are _C1 - _C4 alkyl groups. 17. The method of claim 8 or 9, wherein R ¹¹ and R ¹² are methyl groups. 18. The method of claim 8 or 9, wherein the reaction conditions comprise a compound of formula V, wherein R ¹² is a _C1 - _C4 alkyl group; and wherein the reaction is carried out at a temperature of about 100°C. 19. The method of claim 18, further wherein the reaction is carried out under a nitrogen atmosphere. 20. The method of claim 8 or 9, wherein the reaction conditions further comprise converting the compound of formula VII into the compound of formula IV; Alternatively, compounds of formula VIIA can be converted into compounds of formula IVA. 21. The method of claim 20, wherein the reaction conditions include amines. 22. The method of claim 21, wherein the amine is morpholine. 23. The method of claim 20, wherein the reaction is carried out in dichloromethane. 24. The method of claim 20, wherein the reaction is carried out at a temperature below 25°C. 25. The method of claim 20, wherein the reaction is carried out at a temperature of 0°C to 10°C. 26. The method of claim 20, wherein the reaction conditions include morpholine; and wherein the reaction is carried out in dichloromethane at a temperature of 0°C-10°C. 27. Method for preparing compounds of formula VI: It includes compounds of formula IV that are converted under reaction conditions sufficient to produce compounds of formula VI: in Z is O, NR ¹ , or S; ^R1 is selected from hydrogen and alkyl groups; R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR13- , wherein n is ⁰ , 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom to which they are attached can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; and R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic; and Each R ¹² is independently selected from alkyl, aryl, heteroaryl, and heterocyclic groups. 28. Methods for preparing compounds of formula VIA: It includes compounds that convert to formula IVA under reaction conditions sufficient to produce formula VIA: in R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR13- , wherein n is ⁰ , 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom to which they are attached can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; and R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic; and Each R ¹² is independently selected from alkyl, aryl, heteroaryl, and heterocyclic groups. 29. The method of claim 27 or 28, wherein the reaction conditions include hydrogen. 30. The method of claim 27 or 28, wherein the reaction conditions include a base. 31. The method of claim 30, wherein the base is sodium carbonate. 32. The method of claim 27 or 28, wherein the reaction conditions include ethyl acetate. 33. The method of claim 27 or 28, wherein the reaction conditions include a catalyst. 34. The method of claim 33, wherein the catalyst is Pd/C. 35. The method of claim 27 or 28, wherein the reaction conditions include conditions under pressure. 36. The method of claim 27 or 28, wherein the reaction conditions include conditions at approximately 60 psi pressure. 37. The method of claim 27 or 28, wherein the reaction conditions include hydrogen, sodium carbonate, ethyl acetate, Pd/C, and conditions under pressure. 38. The method of claim 27 or 28, wherein the reaction conditions include hydrogen, sodium carbonate, ethyl acetate, Pd/C, and conditions at a pressure of approximately 60 psi. 39. The method of claim 27 or 28, wherein R ¹² is a _C1 - _C4 alkyl group. 40. The method of claim 27 or 28, wherein R ¹² is methyl. 41. Method for preparing compounds of formula VI: The method includes the following steps: a) Contacting the compound of formula II with the compound of formula III under reaction conditions sufficient to produce the compound of formula I; b) Under reaction conditions sufficient to produce a compound of formula IV, contact a compound of formula I with a compound of formula IV, and subsequently with a compound of formula IV; contact a compound of formula ^R12 - ^X3 , and subsequently with a compound of formula IV; or contact a compound of formula V. c) Optionally, under reaction conditions sufficient to produce a compound of formula IV, convert a compound of formula VII; and d) Converting a compound of formula IV under reaction conditions sufficient to produce a compound of formula VI; wherein Z is O, NR ¹ , or S; ^R1 is selected from hydrogen and alkyl groups; R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR13- , wherein n is ⁰ , 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom to which they are attached can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; and R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic; Each R ¹¹ is independently selected from alkyl, benzyl or aryl, or two R ¹¹ together with the nitrogen atom attached to them form a 4-8 membered heterocyclic group or heteroaryl group; Each R ¹² is independently selected from alkyl, aryl, heteroaryl, and heterocyclic groups, or when two R ^12s are present, the two R ^12s together with the carbon atoms attached to them form a 4-8 membered heterocyclic group; and ^X3 is a halogen. 42. Methods for preparing compounds of formula VIA: The method includes the following steps: a) Contacting the compound of formula IIA with the compound of formula III under reaction conditions sufficient to produce the compound of formula IA; b) Contact the compound of formula IA with the compound of formula V under reaction conditions sufficient to produce the compound of formula IVA; c) Optionally, under reaction conditions sufficient to produce formula IVA, convert a compound of formula VIIA; and d) Converting compounds of formula IVA under reaction conditions sufficient to produce formula VIA; in R ² is selected from hydrogen and unsubstituted alkyl groups or substituted with one or more substituents independently selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 and ^R4 are independently selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0 ^, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- or ^-NR9- , where n is 0, 1 or 2, or ^R3 and ^R4 together with the carbon atom attached thereto form a cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; ^R5 and ^R6 are independently selected from hydrogen, halogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, heteroaryl, substituted heteroaryl and ^–X2R10 , wherein ^X2 is oxygen, -S(O) _n- or ^–NR9- , wherein n is 0 ^, 1 or 2, or when ^X2 is ^–NR13- , ^R13 and ^R10 together with the nitrogen atom to which they are attached can combine to form a heterocyclic or substituted heterocyclic group; Each R ⁸ is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic, provided that R ⁸ is not hydrogen when X ¹ is –SO- or -SO _2- . ^R9 and ^R13 are independently selected from hydrogen, alkyl, and aryl; and R ¹⁰ is selected from alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic and substituted heterocyclic; Each R ¹¹ is independently selected from alkyl, benzyl, or aryl, or two R ^11s together with the nitrogen atom attached to them form a 4-8 membered heterocyclic or heteroaryl group; and Each R ¹² is independently selected from alkyl, aryl, heteroaryl, and heterocyclic groups, or two R ^12s together with the carbon atoms to which they are linked form a 4-8 membered heterocyclic group. 43. The method of claim 41 or 42, wherein the reaction conditions of steps a) and b) include acid. 44. The method of claim 41 or 42, wherein ^R11 and ^R12 are _C1 - _C4 alkyl groups. 45. The method of claim 41 or 42, wherein ^R11 and ^R12 are _C1 - _C4 alkyl groups, and ^R3 , ^R5 and ^R6 are hydrogen. 46. The method of claim 41 or 42, wherein ^R11 and ^R12 are _C1 - _C4 alkyl groups, and ^R4 , ^R5 and ^R6 are hydrogen. 47. The method of claim 41 or 42, wherein ^R11 and ^R12 are methyl groups. 48. Methods for preparing compounds of formula VIC: It includes the following steps: a) Contacting a compound of formula IIC with a compound of formula IIIA under reaction conditions sufficient to produce a compound of formula IC; b) Contacting a compound of formula IC with a compound of formula VA under reaction conditions sufficient to produce a compound of formula IVC; c) Optionally, convert compounds of formula VIIC under reaction conditions sufficient to produce compounds of formula IVC; and d) Converting compounds of formula IVC under reaction conditions sufficient to produce compounds of formula VIC; in R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R4 is selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- ^{or -NR9-} , where n is 0, 1 or 2, or ^R3 , ^R4 together with the carbon atom attached thereto form cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; Each ^R8 is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic, provided that ^R8 is not hydrogen when ^X1 is –SO- or _-SO2- ; and Each ^R9 is selected from hydrogen, alkyl, and aryl. 49. The method of claim 48, further comprising the step of: e) Contacting a compound of formula VIC with glycine under reaction conditions sufficient to produce a compound of formula XC: 50. Methods for preparing compounds of formula VID: It includes the following steps: a) Contacting a compound of formula IID with a compound of formula IIIA under reaction conditions sufficient to produce a compound of formula ID; b) Under conditions sufficient to produce a compound of formula IVD, contact a compound of formula ID with a compound of formula VA; c) Optionally, under conditions sufficient to produce a compound of formula IVD, convert a compound of formula VIID; and d) Converting compounds of formula VID under conditions sufficient to produce compounds of formula IVD; in R ² is selected from hydrogen and unsubstituted alkyl groups or alkyl groups substituted independently with one or more substituents selected from cycloalkyl, heterocycloalkyl, aryl and heteroaryl; ^R3 is selected from hydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl, substituted heteroaryl, halogen, hydroxyl, cyano, -S(O) _n -N( ^R8 ) ^-R8 , where n is 0, 1 or ² , ^-NR8C (O) ^NR8R8 , ^-X1R8 , where ^X1 is oxygen, -S(O) _n- ^{or -NR9-} , where n is 0, 1 or 2, or ^R3 , ^R4 together with the carbon atom attached thereto form cycloalkyl, substituted cycloalkyl, heterocyclic, substituted heterocyclic, aryl, substituted aryl, heteroaryl or substituted heteroaryl; Each ^R8 is independently selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl, substituted heteroaryl, heterocyclic, and substituted heterocyclic, provided that ^R8 is not hydrogen when ^X1 is –SO- or _-SO2- ; and Each ^R9 is selected from hydrogen, alkyl, and aryl. 51. The method of claim 50, further comprising the step of: e) Contacting a compound of formula VID with glycine under conditions sufficient to produce a compound of formula XD: 52. The method of any one of claims 41, 42, 48 or 50, wherein the reaction conditions of step a) include an acid. 53. The method of claim 52, wherein the acid is glacial acetic acid. 54. The method of any one of claims 41, 42, 48 or 50, wherein step a) is performed at a temperature greater than 30°C. 55. The method of any one of claims 41, 42, 48 or 50, wherein step a) is performed at a temperature of 50°C-60°C. 56. The method of any one of claims 41, 42, 48 or 50, wherein step b) is performed at a temperature greater than 30°C. 57. The method of any one of claims 41, 42, 48 or 50, wherein step b) is performed at a temperature of approximately 100°C. 58. The method of any one of claims 41, 42, 48 or 50, wherein the method includes step c). 59. The method of claim 58, wherein the reaction conditions of step c) include amines. 60. The method of claim 59, wherein the amine is morpholine. 61. The method of claim 58, wherein step c) is carried out in dichloromethane. 62. The method of claim 58, wherein step c) is performed at a temperature below 25°C. 63. The method of claim 58, wherein step c) is performed at a temperature of 0°C to 10°C. 64. The method of any one of claims 41, 42, 48 or 50, wherein the reaction conditions of step d) include hydrogen. 65. The method of any one of claims 41, 42, 48 or 50, wherein the reaction conditions of step d) include a base. 66. The method of claim 65, wherein the base is sodium carbonate. 67. The method of claim 65, wherein the reaction conditions of step d) include 0.5-1 molar equivalents of sodium carbonate. 68. The method of any one of claims 41, 42, 48 or 50, wherein the reaction conditions of step d) include ethyl acetate. 69. The method of any one of claims 41, 42, 48 or 50, wherein the reaction conditions of step d) include a catalyst. 70. The method of claim 69, wherein the catalyst is Pd/C. 71. The method of claim 1 or 41, wherein 1.1-1.5 molar equivalents of the compound of formula III are used. 72. The method of claim 2 or 42, wherein 1.1-1.5 molar equivalents of the compound of formula III are used. 73. The method of claim 48 or 50, wherein 1.1-1.5 molar equivalents of a compound of formula IIIA are used. 74. The method of claim 8 or 41, wherein 2-3 molar equivalents of the compound of formula V are used. 75. The method of claim 9 or 42, wherein 2-3 molar equivalents of the compound of formula V are used. 76. The method of claim 48 or 50, wherein 2-3 molar equivalents of a compound of formula VA are used. 77. A compound of formula VIII or a salt thereof: in: Z is either O or S; ^R2 is selected from hydrogen and _C1 - _C10 alkyl groups; ^R3 and ^R4 are independently selected from hydrogen, _C6 - _C14 aryloxy, C6-C14 aryloxy substituted with 1-4 _C1 - _C10 alkoxy or 1-4 halogens, _{C6 - C14} arylthio, and _C6 - _{C14 arylthio substituted with 1-4 C1-C10 alkoxy or 1-4} halogens; ^R5 and ^R6 are independently selected from hydrogen, _C6 - _C14 aryloxy, and _C6 - _C14 arylthio; R ⁷ is –N(R ¹¹ )(R ¹¹ ) or –OC(O)R ¹² ; Each R ¹¹ is independently a _C1 - _C10 alkyl group; and Each R ¹² is independently a _C1 - _C10 alkyl group; The condition is that the compound is not butyl 1-dimethylaminomethyl-4-hydroxy-7-phenylthio-isoquinoline-3-carboxylate. 78. A compound of formula VIIIA or a salt thereof: in: ^R2 is selected from hydrogen and _C1 - _C10 alkyl groups; ^R3 and ^R4 are independently selected from hydrogen, _C6 - _C14 aryloxy, C6-C14 aryloxy substituted with 1-4 _C1 - _C10 alkoxy or 1-4 halogens, _{C6 - C14} arylthio, and _C6 - _{C14 arylthio substituted with 1-4 C1-C10 alkoxy or 1-4} halogens; ^R5 and ^R6 are independently selected from hydrogen, _C6 - _C14 aryloxy, and _C6 - _C14 arylthio; R ⁷ is –N(R ¹¹ )(R ¹¹ ) or –OC(O)R ¹² ; Each R ¹¹ is independently a _C1 - _C10 alkyl group; and Each R ¹² is independently a _C1 - _C10 alkyl group; The condition is that the compound is not butyl 1-dimethylaminomethyl-4-hydroxy-7-phenylthio-isoquinoline-3-carboxylate. 79. The compound of claim 77 or 78, wherein ^R2 is a _C1 - _C10 alkyl group. 80. The compound of claim 79, wherein ^R2 is a methyl group. 81. The compound of claim 77 or 78, wherein ^R3 and ^R4 are independently selected from hydrogen, phenoxy, 4-methoxy-phenoxy, and 3,5-difluoro-phenoxy. 82. The compound of claim 77 or 78, wherein ^R5 and ^R6 are independently selected from hydrogen and phenoxy. 83. The compound of claim 77 or 78, wherein each R ¹¹ is independently a methyl group. 84. The compound of claim 77 or 78, wherein each R ¹² is independently a methyl group. 85. The compound of claim 77 or 78, wherein ^R5 and ^R6 are hydrogen. 86. The compound of claim 77 or 78, wherein: ^R2 is a _C1 - _C10 alkyl group; and ^R5 and ^R6 are hydrogen. 87. The compound of claim 77 or 78, wherein ^R7 is –N( ^R11 )( ^R11 ), and ^R11 is a _C1 - _C4 alkyl group. 88. The compound of claim 77 or 78, wherein R ⁷ is –OC(O)R ¹² and R ¹² is a _C1 - _C4 alkyl group. 89. The compound of claim 77 or 78, wherein: ^R2 is a _C1 - _C10 alkyl group; ^R3 and ^R4 are independently selected from hydrogen, _C6 - _C14 aryloxy, C6-C14 aryloxy substituted with 1-4 _C1 - _C10 alkoxy or 1-4 halogens, _{C6 - C14} arylthio, and _C6 - _{C14 arylthio substituted with 1-4 C1-C10 alkoxy or 1-4} halogens; ^R5 and ^R6 are hydrogen; ^R7 is –N( ^R11 )( ^R11 ); and Each R ¹¹ is independently a _C1 - _C4 alkyl group. 90. The compound of claim 77 or 78, wherein: ^R2 is a _C1 - _C10 alkyl group; ^R3 and ^R4 are independently selected from hydrogen, _C6 - _C14 aryloxy, C6-C14 aryloxy substituted with 1-4 _C1 - _C10 alkoxy or 1-4 halogens, _{C6 - C14} arylthio, and _C6 - _{C14 arylthio substituted with 1-4 C1-C10 alkoxy or 1-4} halogens; ^R5 and ^R6 are hydrogen; ^R7 is –OC(O) ^R12 ; and Each ^R12 is independently a _C1 - _C10 alkyl group.