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CA1111847A - Preparation of quinazoline derivatives - Google Patents

Preparation of quinazoline derivatives

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Publication number
CA1111847A
CA1111847A CA310,645A CA310645A CA1111847A CA 1111847 A CA1111847 A CA 1111847A CA 310645 A CA310645 A CA 310645A CA 1111847 A CA1111847 A CA 1111847A
Authority
CA
Canada
Prior art keywords
signifies
metal
methyl
toluene
quinazolinone
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA310,645A
Other languages
French (fr)
Inventor
Joseph A. Smith
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sandoz AG
Original Assignee
Sandoz AG
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Filing date
Publication date
Application filed by Sandoz AG filed Critical Sandoz AG
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Publication of CA1111847A publication Critical patent/CA1111847A/en
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Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D239/00Heterocyclic compounds containing 1,3-diazine or hydrogenated 1,3-diazine rings
    • C07D239/70Heterocyclic compounds containing 1,3-diazine or hydrogenated 1,3-diazine rings condensed with carbocyclic rings or ring systems
    • C07D239/72Quinazolines; Hydrogenated quinazolines
    • C07D239/78Quinazolines; Hydrogenated quinazolines with hetero atoms directly attached in position 2
    • C07D239/80Oxygen atoms
    • C07D239/82Oxygen atoms with an aryl radical attached in position 4
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P29/00Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Pain & Pain Management (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Rheumatology (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Plural Heterocyclic Compounds (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

ABSTRACT OF THE DISCLOSURE
Novel process for producing 4-aryl-2(1H)-quinazolinones know as anti-inflammatory agents, by dehydrogenating a corresponding 4-aryl-5,6,7,8-tetrahydro-2(1H)-quinazolinone in the presence of an inorganic metal compound.

Description

~$1~ 7 Preparation of Quinazoline Derivatives This invention relates to a process for the prep-aration of 4-aryl-quinazoline-2(lH)-ones, in particular a compound of formula I, R4 IRl R3 R~ I

in which Rl signifies a (Cl-C8) hydrocarbon radical optionally mono-, di or tri-substituted with fluoro, chloro or bromo, R2 signifies monocyclic aryl, and R3 and R4, which may be the same or different, each signifies a hydrogen atom, a (Cl-C
alkyl or alkoxy radical, or fluorine, chlorine, bromine or trifluoromethyl, or R3 and R4 together signify 6,7-methylenedioxy, by dehydrogenating a corresponding 4-aryl-5,6,7,8-tetra-hydro-2(1H)-quinazolinone, in particular a compound of ~111847 formula II, R

~ N`C = O II

in which Rl, R2, R3 and R4 are as defined above, with sulphur, in an inert organic solvent, characterised in that the dehydrogenation is effected in the presence of an inorganic metal compound which is an oxide, hydroxide or salt of a metal, other than magnesium, aluminium, beryllium or an alkali metal, and which forms a metar-sulphide under the reaction conditions.
The process of the invention is suitably effec-ted at temperatures in the range of from 125 to 250C, preferably 130 to 200C and more preferably in the range 135 to 200C.
The reaction is carried out in an organic solvent inert under the reactive conditions. Preferred solvents include ethylene glycol, propylene glycol, ethoxyethoxy-ethanol, dioxane, toluene, xylene and ~-cymeme. It is generally preferred to employ a solvent boiling at the desired reaction temperature in order to utilise reflux conditions, e.y. ~-cymene under the more preferred temperature conditions.

i The mol ratio of sulphur to the quinazolinone starting material may vary fairly widely but is suitably at least 1.7 : 1. The upper limit is not particularly critical, but it is unnecessary and inefficient to employ the sulphur in an amount exceeding a mol ratio of 6 : 1.
More suitably, the mol ratio will be in the range of from 1.9 : l to 4 : 1, preferably in the range of 2 : 1 to 3 : 1.

The metal compound to be employed is, as indicated, one which forms a sulphide under the reaction conditions. In addition to the alkali metals and magnesium and aluminium, as a practical matter the rare earth metals and metals with an atomic number of 84 or greater are not preferred. Pref-erred metals include calcium, titanium, zirconium, chro~ium, lead, molyb~enum, mangane~e, iron, tin, cobalt, nickel, palladium, copper, silver, zinc, cadmium, mercury, antimony and bismuth, more preferably calcium, iron or zinc. The metal compound may be a salt, for example a salt of a strong acid, such as a halide, e.g. chloride, sulphate or nitrate, but is preferably an oxide or hydroxide, pa:rticularly an oxide. The preferred metal compounds include calcium oxide, ~inc oxide and, in particular,ferric oxide. A number of the metal compounds which may be used, e.g. calcium chloride, react with hydrogen sulphide to form an acidic medium and the resulting metal sulphides tend to be unstable or soluble in such medium. In such cases, it is preferred to include ~ 4 ~ 600-~744/X

in the reaction mixture a hydroxide base, e.g. an alkali metal hydroxide or alkaline earth metal hydroxide, or an excess of the metal compound when this is a hydroxide base.
Preferably, an alkali metal hydroxide, e.g. potassium or sodium hydroxide, is used.

The mol ratio of metal compound to the quinazolin-one starting material is suitably at least 1 : 1, preferably at least 1.5 : 1. The upper limit is not critical but mol ratios in excess of 10 : 1 offer no additional advantage.
More suitably, the mol ratio will be in the range of from 1.8 : 1 to 6 : 1, preferably 2 : 1 to 4 : 1 and more pref-erably in the range of from 2.1 : 1 to 3 : 1.

Where employed, the hydroxide base is conveniently present in a mol ratio relative to the quinazolinone starting material, of at least 1 : 1, suitably at least 1.5 : 1, preferably 1.8 to 6 : 1, more pre~erably 2 to 3 : 1.

The process of the present invention may be effec-ted under sub- or super-atmospheric pressure but is most suitably carried out under atmospheric pressure. A blanket or constant flow of a yas, inert under the reaction con-ditions, e.g. nitrogen, over the reaction mixture is pref-er~ed.
The reaction may typically be run from about 1 to 15 hours.

The process of the invention results in substanti-ally higher yields than the corresponding known process, which does not employ a metal compound, and which usually results in a mixture of the desired quinazolin-2(1~)-or.e and the corresponding 3,4-dihydro derivative.

The compounds II are either known ~ se or may be prepared from kno~m materials by methods described in the literature.
In the compounds of the formulae I and I~ the (Cl-C8) hydrocarbon radical of Rl may for example be (Cl-C6) alkyl, (C3-C7) cycloalkyl, (C4-C7~ cycloalkylalkyl, having a (C3-C6) cycloalkyl and a (Cl-C2) alkyl portion, phenyl, benzyl or phenethyl. Examples of halo-substituted hydro-carbon radicais for Rl include (Cl-C6) alkyl, mono~, di-or tri-substituted by fluorine, chlorine or bromine and phenyl, benzyl or phenethyl, mono- or di-substituted by fluorine, chlorine or bromine. Di- or tri-halogen substit-uted radicals are preferably substituted by the same halo~en atoms.
In the compounds of the formula I ~ d II, R2 is more preferably a rad~cal of formula III or IV, ~ lll or ~ y IV

l84'7 in which Y and Yl may be the same or different, each signifies a hydrogen, fluorine, chlorine or bromine atom, a (Cl-C3) alkyl or alkoxy radical, or a trifluoromethyl group, provided that when one of Y and Yl signi-fies a trifluoromethyl group, the other signifies a hydrogen atom, and Y2 signifies a hydrogen, fluorine, chlorine or bromine atom, or a (Cl-C3) alkyl or alkoxy radical.

The compounds of formula I are known for their anti-inflammatory activity and in this regard R1 is prefer-ably (Cl-C6) alkyl or cyclopropylmethyl, more preferably (Cl-C6) alkyl, especially isopropyl. R2 is preferably a phenyl radical optionally mono- or di-substituted as indic-ated above, and is more preferably phenyl or ~-fluorophenyl.
R3 and ~4 may each be hydrogen. Preferably, however, at least one is Cl 3-alkyl, in particular methyl, for example in the 7-position, or Cl 3-alkoxy, e.g. methoxy, for example in the 6-position.

Compounds that are most preferably prepared are 7-methyl-1-isopropyl-4-phenyl-2(1H)-quinazolinone and l-isopropyl-4-~-fluorophenyl-7-methyl-2(lH)-quinazolinone.

The following Examples llustrate the process of ~he invention.

'7 ~ 7 ~ 600-6744/X

EX~IPLE 1: 7-Methyl-l-isopropyl-4-~henvl-2(~ g~uina .
inone A mixture of 200 ml of ~-cymene, 40 g of ferric oxide and 7 g of sulphur is heated to reflu~ (ca. 175C), and there is then added thereto dropwise over a period of 40 minutes a hot (130C) solution of 28.2 g of 7-methyl-l-isopropyl-4-phenyl-5,6,7,8-tetrahydro-2(1Il)-quinazolin-one in 200 ml of ~-cymene. The resulting solution is refluxed for 3.5 hours duriny which time 1.8 ml of water are collected in a Dean Stark separator. The reaction solution is then cooled to 28C and filtered through a Celite pad which is then ~7ashed 4 times each with 25 ml of toluene. Th~ toluene washings are extracted with 50 ml of 4N hydrochloric acid and the ~-cymene filtrate is extracted with 350 ml of 4N hydrochloric acid. T~e ac~d extracts are combined and extracted with 100 ml of toluene~ and such toluene extracts discar~ed. The acid solution remaining after such tolue~e extraction is treated by addition of 350 ml of toluene and 110 g of 50~ aqueous sodium hydroxide solution. The phases are separated and the toluene phase washed twice each with 100 ml of water, followed by drying over sodium sulphate, filtering and evaporation in vacuo. The solid residue is crystallised ~rom ethyl acetate to obtain 7 methyl-l-isopropyl-4-pher.yl-quinazolin-2(1H~-one, m.p. 139-141C.

. ,~.
r ~ '~ .
, - 1$11847 .;

EX~PLE 2~ sopro~yl-4-p-fluoro~henyl-7-methyl-2(lH) quinazolinone A mixture of 67 ml of xylene, 13.3 g of ferric oxide and 2.5 g of sulphur is heated under a nitrogen 5 atmosphere to reflux and there is then added thereto, ;
over a period of 20 minutes drop~Jise, a hot ~100-110C) solution of 10 g of 7-methyl-1-isopropyl-4-~-fluoro-phenyl-5,6,7,8-tetrahydro-2(lH)-quinazolinone in 100 ml of Yylene. The resulting solution is refluxed for 10 hours, during which time water is collected in a Dean Stark separator. The reaction mixture is then cooled to 80C and filtered through a Cellte~iad.

The filtrate and the filter cake are washed 3 times each with 50 ml of toluene. The filtrates are com-bined and then extracted successively with 200, 100 and50 ml of 4N hydrochlorlc acid. The acid extracts are combined and washed with 100 ml of toluene, the toluene extracts being discarded. To the acid solution, remaining after such toluene extraction,aré added 200 ml of toluene and 115 g of 50% aqueous sodium hydroxide solution ~;hilc stirring and cooling. TAe phases are separated and the aqueou~ phase washed twice each with 100 ml of toluene.

~''~' ' .
;
: -.., - . - .
~ '- '" ' ~ ~

84'7 The toluene phases are combined, wached twice each with 100 ml of water, followed by drying over anhydrous magnesium sulphate, filtering through Celite ~
and concentrating to yield 8.8 g (90%) of yellow crystals.
. 5 Recrystallisation occurs from ethylacetate to obtain the title compound with m.p. 175-176.5C.

EX~MPLE 3: 1-Iso~ro~vl-4-Dhenvl-7-methvl-2(1~)-auinazolinone A mixture of 28.2 g of 7-~.ethyl-1-isopropyl-4-phenyl-5,6,7,8-tetrahydro-2(lH)-quinazolinone, 9.6 g of 10 sulphur, 10 g of sodium hydroxide, 20 g of calcium chloride and 200 ml of carbitol (2-[2-ethoxyethoxy]ethanol~
~s heated under a nitrogen blanket at 150C for 2 hours.
The resulting miY.ture is then cooled to 65C, 500 ml of benzene added and the mixture cooled with stirring to 15C
15 and the liquid phase decanted. The organic phase is washed with ~ater and evaporated to obtain an oil which is dissol-ved in a mixture of 100 ml of benzene and 100 ml of 50~
aqueous hydrochloric acid. The xesultiny mixture is stirred for one hour at room temperature, tr.e phases separated and 20 the acid phase treated with 50 ml of benzene~ The acid phase is neutralised with 50~ sodium hydroxide solution, extracted with 150 ml o~ benzene and the benzene extracts washed with water until neu~ral. ~fter drying over sodium sulphate, the benzene sclution is evapcra~ed to obtain the B

crude product which is recrystallised from ethyl acetate to obtaln l-isopropyl-4-phenyl-7-methyl-2(lH)-quinazolinone, m.p. 141-142C.

EXAMPL~ 4: 7-Methyl-l-isopro~yl-4-(p-fluorophenvl)-quin azolin-2-(lH)-one To a stirred mixture of 4.3 g of sulphur, 6.8 g of zinc oxide and 67 ml of a mixture of xylenes heated to reflux (ca. 138C) under a nitrogen blanket is added a pre-heated (100-115C) solution of 10.0 g of 7-methyl-1-isopropyl-4-(~-fluorophenyl)-5,6,7,8-tetrahydro-2(1~)-quinazolinone in 100 ml of a mixture of xylenes. After addition'(ca. 20 m-nutes), the resulting ~ixture is refluxed overnight, cooled and filtered through Cellte. The solids ~
are washed with toluene and the filtrate and washin~s ex-tracted four times with 4N hydrochloric acid and the extractswashed with 100 ml of toluéne. The aqueous phase is treated with 200 ml of toluene and treated portionwise with 115 g of 50~ sodium hydroxide solution in an ice-bath. The aqueous phase is extracted twice each with 100 ml of toluene and the organic phase water washed and dried. The crude yellow solid obtained on filtering and concentration in vacuo is dissolved in 100 ml of ethyl acetate, filtered and concentrated to a volume o, 50 ml and cooled to 0C to ~ '.

- 11 - 6oo-G744/x obtain a precipitate which is recrystallised from ethyl acetate to yield 7-methyl-1-isopropyl-4~ fluorophenyl)-quinazolin-2(lH)-one.

EXAMPLE 5:
The procedure of Example 4 is repeated employing an equivalent molar amount of lead dioxide in place of zinc oxide to yield the same product.

EXAMPLE 6:
In a manner analogous to any one of the preceding Exampies and employing appropriate starting materials in approximately equivalent amounts, the following compounds may be obtained:-5,7-dimethyl-1-isopropyl-4-phenyl-quinazolin-2~lH)-one;
l-isopropyl-7-methyl-4-(~-methylphenyl)-quinazolin-2(lH)-one;l-isopropyl~7-methyl-4-(2-thienyl)-quinazolin-2(1H)-one;
l-cyciopropylme~hyl-6-methoxy-4-phenyl-quinazolin-2(lH)-one.

Claims (2)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. A process for the production of a compound of formula I, I

in which R1 signifies a (C1-C8) hydrocarbon radical optionally mono-, di- or tri-substituted with fluoro, chloro or bromo R2 signifies monocyclic aryl, and R3 and R4, which may be the same or different, each signifies a hydrogen atom, a (C1-C3) alkyl or alkoxy radical, or fluorine, chlorine, bromine or trifluoro-methyl, or R3 and R4 together signify 6,7-methylenedioxy, by dehydrogenating a corresponding 5,6,7,8-tetrahydro-
2(1H)-quinazolinone of the formula II, II

in which R1, R2, R3 and R4 are as defined above, with sulphur, in an inert organic solvent, characterised by performing the dehydrogenation in the presence of an inorganic metal compound which is an oxide, hydroxide or salt of a metal, other than magnesium, aluminium, beryllium or an alkali metal, and which forms a metal sulphide under the reaction conditions.
CA310,645A 1977-09-06 1978-09-05 Preparation of quinazoline derivatives Expired CA1111847A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US83041177A 1977-09-06 1977-09-06
US830,411 1977-09-06

Publications (1)

Publication Number Publication Date
CA1111847A true CA1111847A (en) 1981-11-03

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JP (1) JPS5455583A (en)
AR (1) AR228235A1 (en)
AT (1) AT376211B (en)
AU (1) AU523728B2 (en)
BE (1) BE870185A (en)
CA (1) CA1111847A (en)
CH (1) CH642638A5 (en)
DD (1) DD138657A5 (en)
DE (1) DE2837403A1 (en)
DK (1) DK144999C (en)
ES (1) ES473103A1 (en)
FI (1) FI66362C (en)
FR (1) FR2401917A1 (en)
GB (1) GB2003873B (en)
GR (1) GR73605B (en)
HU (1) HU183018B (en)
IE (1) IE47184B1 (en)
IL (1) IL55492A (en)
IT (1) IT1106289B (en)
NL (1) NL7808981A (en)
NO (1) NO782945L (en)
NZ (1) NZ188329A (en)
PL (1) PL114207B1 (en)
PT (1) PT68505A (en)
SE (1) SE7809098L (en)
SU (1) SU900810A3 (en)
YU (1) YU211078A (en)
ZA (1) ZA785061B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH637114A5 (en) * 1978-08-16 1983-07-15 Sandoz Ag 2- (N-CARBOALKOXYAMINO) -BENZOPHENONE, THEIR PRODUCTION AND USE.
CH645362A5 (en) * 1979-07-05 1984-09-28 Sandoz Ag METHOD FOR PRODUCING 4-PHENYL-2 (1H) -QUINAZOLINONES.
GB0230015D0 (en) * 2002-12-23 2003-01-29 Novartis Ag Organic compounds

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE785937A (en) * 1971-07-08 1973-01-08 Sandoz Sa NEW DERIVATIVES OF QUINAZOLINE, THEIR PREPARATION AND THEIR APPLICATION AS MEDICINAL PRODUCTS

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Publication number Publication date
PL114207B1 (en) 1981-01-31
PT68505A (en) 1978-10-01
ZA785061B (en) 1980-04-30
DK144999B (en) 1982-07-26
YU211078A (en) 1982-10-31
AU523728B2 (en) 1982-08-12
IT1106289B (en) 1985-11-11
AT376211B (en) 1984-10-25
NZ188329A (en) 1981-05-15
GR73605B (en) 1984-03-26
AR228235A1 (en) 1983-02-15
IL55492A0 (en) 1978-12-17
IT7850936A0 (en) 1978-09-01
CH642638A5 (en) 1984-04-30
GB2003873A (en) 1979-03-21
BE870185A (en) 1979-03-05
NL7808981A (en) 1979-03-08
FR2401917B1 (en) 1982-12-17
JPS5455583A (en) 1979-05-02
NO782945L (en) 1979-03-07
IE781780L (en) 1979-03-06
DD138657A5 (en) 1979-11-14
ES473103A1 (en) 1979-04-01
ATA639978A (en) 1984-03-15
DE2837403A1 (en) 1979-03-08
FR2401917A1 (en) 1979-03-30
IL55492A (en) 1982-08-31
PL209423A1 (en) 1979-06-04
IE47184B1 (en) 1984-01-11
DK144999C (en) 1982-12-13
FI782619A7 (en) 1979-03-07
HU183018B (en) 1984-04-28
SU900810A3 (en) 1982-01-23
FI66362B (en) 1984-06-29
GB2003873B (en) 1982-03-10
AU3957178A (en) 1980-03-13
SE7809098L (en) 1979-03-07
FI66362C (en) 1984-10-10
DK382078A (en) 1979-03-07

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