US20030027823A1

US20030027823A1 - N,N'-disubstituted benzimidazolone derivatives with affinity at the serotonin and dopamine receptors

Info

Publication number: US20030027823A1
Application number: US09/933,598
Authority: US
Inventors: Enzo Cereda; Luciano Maiocchi; Alessandro Brambilla; Ettore Giraldo; Eugenia Monferini; Giovanni Schiavi
Original assignee: Individual
Current assignee: Sprout Pharmaceuticals Inc
Priority date: 2000-09-19
Filing date: 2001-08-21
Publication date: 2003-02-06
Anticipated expiration: 2021-08-21
Also published as: US6521623B1

Abstract

A compound of formula (I)

wherein:

R¹is C₁-C₆-alkyl substituted by a group selected from OH, C₁-C₆-alkoxy, —OCONHC₁-C₆-alkyl, —OCONHC₁-C₆-alkyl, —NHSO₂C₁-C₆-alkyl, and —NHCOC₁-C₆-alkyl, or

R¹is C₁-C₆-alkyl substituted by a saturated or unsaturated 5- or 6-membered heterocycle containing one or two heteroatoms selected from the group consisting of nitrogen and oxygen, the heterocycle optionally substituted by a group selected from C₁-C₄-alkyl, halogen, and benzyl;

R²and R³together with the nitrogen form a saturated or unsaturated 5- or 6-membered heterocyclic ring optionally containing nitrogen or oxygen as an additional heteroatom, the heterocyclic ring thereof substituted by a group selected from phenyl, benzyl, and diphenylmethyl, each of these groups optionally mono- or di-substituted by one or two groups selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, benzyl, halogen, and OH, or

R²and R³together with the nitrogen form a saturated or unsaturated 5- or 6-membered heterocyclic ring optionally containing nitrogen or oxygen as an additional heteroatom, the heterocyclic ring thereof linked via a single bond, a methylene-bridge, or spiro-connected to a saturated or unsaturated heterocyclic group containing one or two heteroatoms selected from oxygen and nitrogen, the heterocyclic group optionally mono- or di-substituted by a group selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, benzyl, halogen, ═O, and OH, or

R²and R³together with the nitrogen form a saturated or unsaturated bi- or tricyclic heterocyclic ring-system optionally containing nitrogen or oxygen as an additional heteroatom, the heterocyclic ring-system being optionally substituted by a group selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, benzyl, halogen, ═O, and OH; and

A is C₁-C₆-alkylene, C₂-C₆-alkenylene, or C₂-C₆-alkynylene,

their pharmaceutically acceptable salts, their preparation, and their use for therapeutic purposes.

Description

The present invention relates to novel pharmacologically active N,N-disubstituted benzimidazolone derivatives and their addition salts which bind the serotonin or dopamine receptors, to their preparation and their use for therapeutic purposes. These compounds are able to discriminate the different serotonin and dopamine receptor subtypes like 5-HT _1A, 5-HT_2A, and D₄at which they can act as agonists or antagonists. Owing to this pharmacological activity, the present compounds are useful in the treatment of anxiety disorders, affective disorders such as depression, psychosis and schizophrenia, eating disorders, sexual disorders, Parkinson, stroke and traumatic brain injury.

BACKGROUND OF THE INVENTION

Serotonin (5-HT) and dopamine (DA) recognize several well defined cell surface receptor subtypes. Among these, 5-HT _1Aand 5-HT2A having a high and a low affinity for 5-HT, respectively, and D₄at which DA has high affinity, have been implicated in many Central Nervous System (CNS) disorders.

In the previous art, several classes of compounds able to interfere with the neurotransmission at 5-HT or DA receptor subtypes are known. Particularly, derivatives based on the core structure of the aryl piperazine and benzimidazolone have been described (e.g., GB 2023594, U.S. Pat. No. 3,472,854, U.S. Pat. No. 4,954,503, WO-9616949, WO-9501965, and WO-9833784), and targeted both to generic 5-HT or DA receptors and to a specific receptor subtype. In another patent (U.S. Pat. No. 5,576,318) are described compounds based both on the benzimidazolone and phenylpiperazine structures: in this latter case the described affinities are limited to 5-HT _1Aand 5-HT_2Areceptor subtypes.

DETAILED DESCRIPTION OF THE INVENTION

Now we describe, and this is the object of the present invention, new derivatives of a benzimidazolone core structure. The N-substituents are alkyl chains bearing additional hydrophilic functional groups whereas the N′-substituents are alkyl or alkenyl spacers connecting the benzimidazolone scaffold to a large set of secondary amines bearing other diversity points. The compounds included in this invention possess an interesting affinity profile at the said serotonin and dopamine receptor subtypes: indeed some of them have a high and preferential affinity at a given site (e.g., 5-HT _1A, 5-HT_2A, or D₄) whereas some others have a mixed affinity at the said receptors. Moreover, a selected pool of compounds possesses an agonistic activity at the 5-HT_1Areceptor coupled with an antagonistic activity at the 5-HT_2Areceptor. Owing to their peculiar profile, the present compounds may play a role in the regulation of neurotransmission at the serotonin and/or the dopamine sites and thus may be of value in the treatment of those diseases where an altered functioning of neurosignal transmission is present. Examples of these disorders include anxiety, depression, schizophrenia, Parkinson, sleep, sexual and eating disorders, stroke and brain injury. Particularly the compounds included in the present invention can be of value in the treatment of depression according to the mounting evidence that 5-HT_1Afull agonists or high efficiency partial agonists are required for a robust antidepressant effect. In fact, electrophysiology studies suggest that repeated administration of a variety of antidepressant treatments facilitate 5-HT_1Aneurotransmission in the hippocampus, possibly through either an increased sensitivity of post-synaptic 5-HT_1Areceptors or a decreased sensitivity of 5-HT_1Aautoreceptors. Furthermore, there is some evidence from controlled clinical trials to support this suggestion. In addition the compound's ability to block the 5-HT_2Areceptor is also of value: indeed, the stimulation of 5-HT_1Aand 5-HT_2Areceptors lead to opposite electrical events, inhibitory and excitatory, respectively. Thus only a concurrent activation of 5-HT_1Acoupled with antagonism at 5-HT_2Areceptors may completely and rapidly inhibit 5-HT post-synaptic cells, an important physiological event for antidepressant effects.

The present invention pertains to compounds of general formula (I)

wherein:

R ¹denotes C₁-C₆-alkyl, preferably C₁-C₄-alkyl, being substituted by a group selected from OH, C₁-C₆-alkoxy, —OCONHC₁-C₆-alkyl, —OCONHC₁-C₆-alkyl, —NHSO₂C₁-C₆-alkyl, and —NHCOC₁-C₆-alkyl, or

R ¹denotes C₁-C₆-alkyl, preferably C₁-C₄-alkyl, being substituted by a saturated or unsaturated 5- or 6-membered heterocycle containing one or two heteroatoms selected from the group consisting of nitrogen and oxygen, said heterocycle being optionally substituted by a group selected from C₁-C₄-alkyl, halogen, and benzyl;

R ²and R³together with the nitrogen form a saturated or unsaturated 5- or 6-membered heterocyclic ring which may contain nitrogen or oxygen as an additional heteroatom, whilst the heterocyclic ring is substituted by a group selected from phenyl, benzyl, and diphenylmethyl, said group being optionally mono- or di-substituted by one or two groups selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, benzyl, halogen, and OH, or

R ²and R³together with the nitrogen form a saturated or unsaturated 5- or 6-membered heterocyclic ring which may contain nitrogen or oxygen as an additional heteroatom, said heterocyclic ring being linked via a single bond, a methylene-bridge or spiro-connected to another saturated or unsaturated heterocyclic group containing one or two heteroatoms selected from oxygen and nitrogen, said heterocyclic group being optionally mono- or di-substituted by a group selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, benzyl, halogen, ═O, and OH, or

R ²and R³together with the nitrogen form a saturated or unsaturated bi- or tricyclic heterocyclic ring-system which may contain nitrogen or oxygen as an additional heteroatom, said heterocyclic ring-system being optionally substituted by a group selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, benzyl, halogen, ═O, and OH;

A denotes C ₁-C₆-alkylene, preferably C₁-C₄-alkylene, C₂-C₆-alkenylene, preferably C₂-C₄-alkenylene, or C₂-C₆-alkynylene, preferably C₂-C₄-alkynylene,

or a pharmaceutically acceptable salt thereof.

Preferred compounds are those of formula (I), wherein:

R ¹denotes C₁-C₄-alkyl, preferably C₂-C₃-alkyl, being substituted by a group selected from OH, C₁-C₄-alkoxy, —OCONHC₁-C₄-alkyl, —OCONHC₁-C₄-alkyl, —NHSO₂C₁-C₄-alkyl, and —NHCOC₁-C₄-alkyl, or

R ¹denotes C₁-C₄-alkyl, preferably C₂-C₃-alkyl, being substituted by a saturated or unsaturated 6-membered heterocycle containing one or two heteroatoms selected from the group consisting of nitrogen and oxygen; p R²and R³together with the nitrogen form a saturated or unsaturated 5- or 6-membered heterocyclic ring which may contain nitrogen as an additional heteroatom, whilst the heterocyclic ring is substituted by a group selected from phenyl, benzyl, diphenylmethyl, pyridinyl, pyrimidinyl, benzimidazolonyl, and 3,4-methylenedioxibenzyl, said group being optionally mono- or di-substituted by a group selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, halogen, and OH;

A denotes C ₁-C₄-alkylene or C₂-C₄-alkenylene,

or a pharmaceutically acceptable salt thereof.

Also preferred compounds are those of formula (I), wherein:

R ¹denotes ethyl, being substituted by a group selected from OH, OCH₃, OCH₂CH₃, —OCONHCH₃, —OCONHCH₂CH₃, —NHSO₂CH₃, —NHSO₂CH₂CH₃, —NHCOCH₃, —NHCOCH₂CH₃, morpholinyl, piperazinyl, and piperidinyl

R ²and R³together with the nitrogen form a 6-membered saturated or unsaturated heterocyclic ring which may contain nitrogen as an additional heteroatom, whilst the heterocyclic ring is substituted by a group selected from phenyl, pyridinyl, pyrimidinyl, benzimidizalonyl, and substituted phenyl being mono- or di-substituted by a group selected from CF₃, CH₃, OCH₃, F, and Cl;

A denotes C ₁-C₄-alkylene or C₂-C₄-alkenylene,

or a pharmaceutically acceptable salt thereof.

Also of interest are compounds of formula (I), wherein:

R ¹denotes ethyl, being substituted by a group selected from OH, OCH₃, —OCONHCH₂CH₃, —NHSO₂CH₃, —NHCOCH₃, morpholinyl, and piperidinyl;

R ²and R³together with the nitrogen form a 6-membered saturated or unsaturated heterocyclic ring which may contain nitrogen as an additional heteroatom, whilst the heterocyclic ring is substituted by a group selected from pyridinyl, phenyl, and substituted phenyl being mono- or di-substituted by a group selected from CF₃, CH₃, OCH₃, F, and Cl;

A denotes ethylene, propylene, butylene, or butenylene,

or a pharmaceutically acceptable salt thereof.

Of particular interest are compounds of formula (I), wherein:

R ²and R³together with the nitrogen form a ring selected from the group consisting of piperazine, piperidine, and tetrahydropyridine, which is substituted by a group selected from pyridinyl, phenyl, and substituted phenyl being mono- or di-substituted by a group selected from CF₃, CH₃, and Cl;

A denotes ethylene, butylene, or butenylene,

or a pharmaceutically acceptable salt thereof.

Furthermore preferred are compounds of formula (I), wherein:

R ¹denotes ethyl, being substituted by a group selected from OH, OCH₃, —OCONHCH₂CH₃, and —NHSO₂CH₃;

R ²and R³together with the nitrogen form a piperazine ring, being substituted by a group selected from trifluoromethylphenyl, methylphenyl, dimethylphenyl, and chlorophenyl; and

A denotes ethylene, butylene, or butenylene,

or a pharmaceutically acceptable salt thereof.

The most preferred compounds according to the invention are:

(a) 1-(2-methoxyethyl)-3-(4-{4-[3-(trifluoromethyl)phenyl]-1-piperazinyl}butyl)-1,3-dihydro-2H-benzimidazol-2-one;

(b) 1-{4-[4-(2,3-dimethylphenyl)-1-piperazinyl]butyl}-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one;

(c) 2-[2-oxo-3-(4-{4-[3-(trifluoromethyl)phenyl]-1-piperazinyl}butyl)-2,3-dihydro-1H-benzimidazol-1-yl]ethyl-ethylcarbamate;

(d) 1-(2-methoxyethyl)-3-(2-{4-[3-(trifluoromethyl)phenyl]-1-piperazinyl}ethyl)-1,3-dihydro-2H-benzimidazol-2-one;

(e) 1-{2-[4-(2,3-dimethylphenyl)-1-piperazinyl]ethyl}-3-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one;

(f) 1-{2-[4-(3-chlorophenyl)-1-piperazinyl]ethyl}-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one;

(g) 2-[2-oxo-3-(2-{4-[3-(trifluoromethyl)phenyl]-1-piperazinyl}ethyl)-2,3-dihydro-1H-benzimidazol-1-yl]ethyl-ethylcarbamate;

(h) 2-(3-{2-[4-(2,3-dimethylphenyl)-1-piperazinyl]ethyl}-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl-ethylcarbamate;

(i) N-[2-(3-{2-[4-(2,3-dimethylphenyl)-1-piperazinyl]ethyl}-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl]methanesulfonamide;

(j) N-[2-(3-{(2Z)-4-[4-(3-methylphenyl)-1-piperazinyl]-2-butenyl}-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl]methanesulfonamide; and

(k) N-[2-(3-{(2E)-4-[4-(3-chlorophenyl)-1-piperazinyl]-2-butenyl}-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl]methanesulfonamide.

If required, the compounds of general formula (I) may be converted into the salts thereof, particularly, for pharmaceutical use, into the pharmaceutically acceptable salts thereof with an inorganic or organic acid. Suitable acids for this purpose include hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, methanesulfonic acid, acetic acid, fumaric acid, succinic acid, lactic acid, citric acid, tartaric acid, or maleic acid. Moreover, mixtures of these acids may be used.

The alkyl groups meant here (including those which are components of other groups) are branched and unbranched alkyl groups having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, such as: methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, and hexyl.

The alkylene groups meant here are branched and unbranched alkyl-bridges having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, such as: methylene, ethylene, n-propylene, isopropylene, butylene, isobutylene, sec-butylene, tert-butylene, pentylene, isopentylene, and hexylene.

Alkenyl groups (including those which are components of other groups) are the branched and unbranched alkenyl groups with 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, provided that they have at least one double bond, e.g., the alkyl groups mentioned above provided that they have at least one double bond, such as for example vinyl (provided that no unstable enamines or enolethers are formed), propenyl, isopropenyl, butenyl, pentenyl, and hexenyl.

Alkenylene groups are the branched and unbranched alkenyl-bridges with 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, provided that they have at least one double bond, e.g., the alkylene groups mentioned above provided that they have at least one double bond, such as for example vinylene (provided that no unstable enamines or enolethers are formed), propenylene, isopropenylene, butenylene, pentenylene, and hexenylene.

If not otherwise specified the alkenyl- and alkenylene-groups mentioned above are to be understood as embracing optionally existing stereoisomers. Accordingly, for instance the definition 2-butenyl is to be understood as embracing 2-(Z)-butenyl and 2-(E)-butenyl, etc.

The term alkynyl groups (including those which are components of other groups) refers to alkynyl groups having 2 to 6, preferably 2 to 4 carbon atoms, provided that they have at least one triple bond, e.g., ethynyl, propargyl, butynyl, pentynyl, and hexynyl.

Examples of N-linked 5- or 6-membered heterocyclic rings of general formula NR ²R³are as follows: pyrrole, pyrroline, pyrrolidine, piperidine, piperazine, morpholine, imidazole, imidazoline, imidazolidine, pyrazole, pyrazoline, and pyrazolidine, preferably morpholine, piperazine, and piperidine.

Examples of saturated or unsaturated bi- or tricyclic heterocyclic ring-system of formula NR ²R³which may contain nitrogen or oxygen as an additional heteroatom, are as follows: indole, tetrahydroindole, benzimidazole, benzoxazole, 1,2-dihydrochinoline, 1,2-dihydroisochinoline, β-carboline, 9H-1,2,3,4-tetrahydropyridoindole, and 9,10-dihydroacridine.

Halogen means fluorine, chlorine, bromine, or iodine, preferably chlorine or bromine.

“═O” means an oxygen atom linked by a double bond.

The compounds of general formula (I) may be conveniently prepared by a variety of synthetic processes analogous to those known in the art using conventional methods. For example, these compounds may be prepared by alkylating the suitable secondary amine (III) with the proper benzimidazolone (II) bearing in the alkyl or alkenyl side chain suitable leaving group X such as halogen, methanesulfonate, or 4-methylbenzenesulfonate (Scheme 1).

Scheme 1

The reaction conditions for the conventional synthesis of compounds of formula (I) according to Scheme 1 are disclosed in EP 526 434 A1. Said reference additionally describes the possible synthetic pathways for the preparation of starting compounds (II).

According to a second option, the reaction sequence according to Scheme 1 can not only be conducted via the conventional synthetic methods outlined in EP 526 434 A1 but, in the alternative, via combinatorial chemistry. For this approach a set of N-alkyl-N′-halo alkyl/alkenyl benzimidazolones of formula (II) (hereinafter identified as Building Blocks or BB; see hereto Table 1) was prepared via the traditional methods described in EP 526 434 A1 and then combinatorially reacted with the suitable secondary amines of formula (III) (Table 2). The process was carried out in a special apparatus consisting of a lower vial (reacting chamber) and an upper vial (condenser). Each compound was reacted with each amine in DMF under stirring at a temperature between 40° C. and 100° C., preferably at 60° C., for 6 to 8 hours in the presence of Na ₂CO₃. The excess amine was then scavenged at room temperature by introducing a polystyrene isocyanatemethyl resin of formula (IV) able to catch the excess amine as an urea of formula (V) immobilized on the solid support (Scheme 2).

Scheme 2

The upper part of the reaction apparatus is substituted with another vial containing a frit inside and a connection to the vacuum. Filtration after turning over the apparatus and evaporation to dryness afforded the desired compounds of formula (I) in excellent yield and good purity. The parallel application of the aforementioned process to all of the compounds of formula (II) as shown in Table 1 and all of the selected amines (III) as shown in Table 2 allows the efficient synthesis of all of the compounds (I) according to the present invention.

TABLE 1


Building Blocks (BB) of Formula (II) Subjected to the Process of Scheme 2

(II)

Building		Building
Block No.	Structure	Block No.	Structure


BB01		BB02

BB03		BB04

BB05		BB06

BB07		BB08

BB09		BB10

BB11		BB12

BB13		BB14

BB15		BB16

BB17		BB18

BB19		BB20

BB21		BB22

BB23		BB24

BB25		BB26

BB27		BB28

TABLE 2


Amines (AM) of Formula (III) Subjected to the Process of Scheme 2

(III)

Amine No.	Structure	Amine No.	Structure


AM01		AM02

AM03		AM04

AM05		AM06

AM07		AM08

AM09		AM10

AM11		AM12

AM13		AM14

AM15		AM16

AM17		AM18

AM19		AM20

AM21		AM22

For pharmaceutical use, the compounds of general formula (I) may be used as such or in the form of physiologically acceptable acid addition salts. The term “physiologically acceptable acid addition salts” includes the salts resulting from both organic and inorganic acids such as maleic, citric tartaric, methanesulfonic, acetic, benzoic, succinic, gluconic, isethionic, glycinic, lactic, malic, mucoic, glutammic, sulfamic, and ascorbic acids; inorganic acids include hydrochloric, hydrobromic, nitric, sulfuric, or phosphoric acid.

According to a further feature of the present invention, there are provided pharmaceutical compositions comprising as an active ingredient at least one compound of formula (I), as before defined, or a physiologically acceptable addition salt thereof in addition to one or more pharmaceutical carrier, diluents or excipients. For pharmaceutical administration, the compounds of general formula (I) and their physiologically acceptable acid addition salts may be incorporated into the conventional pharmaceutical preparation in solid, liquid, or spray form. The composition may, for example, be presented in a form suitable for oral, rectal, or parenteral administration or for nasal inhalation: preferred forms include, for example, capsules, tablets, coated tables, ampoules, suppositories, and nasal spray. The active ingredient may be incorporated in excipients or carriers conventionally used in pharmaceutical compositions such as, for example, talc, arabic gum, lactose, gelatine, magnesium stearate, corn starch, aqueous or nonaqueous vehicles, polyvinyl pyrrolidone, semisynthetic glycerides of fatty acids, benzalcon chloride, sodium phosphate, EDTA, or polysorbate 80.

In case it is desired to further increase the solubility of the compounds of general formula (I) or of their physiologically acceptable salts, surfactants or nonionic surfactants such as PEG 400, cyclodextrin, metastable polymorphs, or inert adsorbents such as bentonite, may be incorporated. Furthermore, some techniques may be employed by preparing, for example, eutectic mixtures and/or solid dispersion by using mannitol, sorbitol, saccharose, or succinic acid or physically-modified forms by using hydrosoluble polymers, PVP, or PEG 4000-20,000. The compositions are advantageously formulated in dosage units, each dosage unit being adapted to supply a single dose of the active ingredient. Each dosage unit may conveniently contain from 0.01 mg to 100 mg, preferably from 0.1 to 50 mg.

However, it could be necessary to depart from the cited amounts, depending on the body weight or on the administration route, on the individual response to the medicament, on the type of formulation and on the time, or time range, in which the administration is carried out. Therefore, it can be sufficient, in some cases, to use a lower amount then the cited minimum amount, whereas in other cases the higher range could be exceeded. When administering higher amounts, it would be advisable to subdivide them in repeated administrations during the day. Moreover, the compounds of general formula (I) or the acid addition salts thereof can also be combined with other, different active substances.

The following examples illustrate the present invention, without limiting the scope thereof. [0073]
Examples of Pharmaceutical Formulations [0074]

A. Tablets Containing 100 mg of Active Substance

Component Amount per tablet (mg)

active substance 100

lactose 140

maize starch 240

polyvinylpyrrolidone 15

magnesium stearate 5

TOTAL 500

The finely ground active substance, lactose, and part of maize starch are mixed. The mixture is sieved, wetted with a solution of polyvinylpyrrolidone in water, kneaded, finely granulated, and dried. The granulate, the remaining maize starch, and magnesium stearate are sieved and mixed together. The mixture is compressed to tablets of suitable form and size.

B. Tablets Containing 80 mg of Active Substance

	Component	Amount per tablet (mg)

	active substance	80
	lactose	55
	maize starch	190
	polyvinylpyrrolidone	15
	sodium carboxymethyl starch	23
	magnesium stearate	2
	TOTAL	400

The finely ground active substance, part of the maize starch, lactose, microcrystalline cellulose and polyvinylpyrrolidone are mixed. The mixture is sieved and worked up with the remaining maize starch and water, to obtain a granulate, which is dried and sieved. This is added to sodium carboxymethyl starch and magnesium stearate and mixed, and the mixture is then compressed to tablets of suitable size. [0076]

C. Solutions for Vials

Component Amount

active substance 50 mg

sodium chloride 50 mg

water for injection 5 ml
The active substance is dissolved in water, optionally at pH of 5.5 to 6.5, and treated with sodium chloride as an osmolality agent. The resulting solution is filtered apyrogenically, and the filtrate is placed in vials under aseptic conditions, then the vials are sterilized and flame sealed. The vials contain 5 mg, 25 mg, and 50 mg of active substance. [0077]
Experimental [0078]
The following examples illustrate the preparation of all the new compounds included in the present invention. It should be understood that the invention is not limited to the given examples of chemical methods and processes for the preparation of the substances, as other conventional methods well known to those skilled in the art, are suitable too. In the following descriptions, each of the 28 Building Blocks prepared is identified by its relevant Tag. [0079]
A. Preparation of the Building Blocks (BB) of Formula (II) [0080]
Description 1 [0081]
1-[2-(1-piperidinyl)ethyl)-1,3-dihydro-2H-benzimidazol-2-one [0082]
A solution of 1-isopropenyl-1,3-dihydro-2H-benzimidazol-2-one (35 g, 0.2 moles) in DMF (250 ml) was added dropwise to a suspension of 80% sodium hydride (6 g, 0.2 moles) in DMF (50 ml). The reaction mixture was first heated at 45° C. for 30 minutes, allowed to cool at room temperature, and an additional amount of 80% sodium hydride (7.2 g, 0.24 moles) was added. Then 1-(2-chloroethyl)piperidine hydrochloride (44.16 g, 0.24 moles) was added portionwise and the reaction mixture was heated at 80° C.-90° C. for 3 hours. The mixture was then cooled at room temperature, adjusted to pH 3 with 37% aqueous HCl, and heated to 80° C. for additional 2 hours. The reaction mixture was poured into water and washed with ethyl acetate. The aqueous phase was adjusted to pH 8-9 with a saturated sodium carbonate solution and extracted into ethyl acetate. The organic layer was taken to dryness to give an ivory solid which after crystallization from isopropyl ether afforded 22.9 g of the title compound. M.p. 123° C.-125° C. [0083]
According to the above described procedure, the following compound was prepared from the suitable intermediates: [0084]
1-[2-(4-morpholinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0085]
11.7 g; m.p. 122° C.-126° C. [0086]
Description 2 [0087]
1-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0088]
Phenyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxylate (80 g, 0.315 moles) was added to a suspension of 80% sodium hydride (11.3 g, 0.378 moles) in DMF (500 ml) and heated at 35° C. for 1 hour. To the cooled solution, 2-chloroethylmethylether (43 ml, 0.472 moles) was added and the reaction mixture was heated at 100° C. for 4 hours. The reaction mixture was poured into water and extracted with ethyl acetate. The combined extracts were taken to dryness to give 52 g of the protected intermediate. This was suspended in methanol (500 ml), a solution of K[0089] ₂CO₃(44 g) in water (230 ml) was added, and the mixture and stirred for 2 hours at room temperature. After evaporation, the reaction mixture was acidified and extracted into ethyl acetate. The organic layer was taken to dryness and from the crude oily residue, after crystallization with isopropyl ether, 21 g of the title compound was obtained as a white solid. M.p. 88° C.
Description 3 [0090]
1-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0091]
(a) Phenyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxylate (50 g, 0.197 moles) was added to a suspension of 80% sodium hydride (7 g, 0.236 moles) in DMF (400 ml) and stirred for 1 hour at room temperature, then 2-(2-chloroethoxy)tetrahydro-2H-pyran (34.8 ml, 0.236 moles) was added and the reaction mixture was heated at 100° C. for 7 hours. The reaction mixture was then poured into water and extracted into ethyl acetate. The organic layer was taken to dryness to give an oily residue. [0092]
(b) This residue (83 g) was dissolved in methanol, a solution of KOH (26 g in 260 ml water) was added and stirred for 2 hours at room temperature. The methanol was evaporated and the residue was extracted into ethyl acetate. The organic layer was washed with an aqueous 5% HCl solution, dried, and taken to dryness. The oily residue was crystallized from diisopropyl ether to give 26 g of the title compound. M.p. 115° C. [0093]
Description 4 [0094]
1-(2-aminoethyl)-1,3-dihydro-2H-benzimidazol-2-one hydrochloride [0095]
(a) A suspension of phenyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxylate (10 g, 39 mmoles) and 80% sodium hydride (1.3 g, 43 mmoles) in DMF (100 ml) was stirred at room temperature for 30 minutes. N-(2-bromoethyl)phthalimide (10 g, 39 mmoles) was added and the mixture heated at 100° C. for 12 hours. The reaction mixture was then poured into 600 ml of water and stirred for 4 hours at room temperature. The precipitated phthaloyl derivative was filtered off (white solid; 6.5 g). [0096]
(b) This intermediate was suspended in methanol (70 ml), a 10% aqueous K[0097] ₂CO₃solution was added and the reaction mixture stirred overnight at room temperature. The methanol was evaporated, the residue was extracted with dichloromethane, and the aqueous solution was acidified with 10% aqueous HCl to give the corresponding 2-carboxybenzamido derivative which was filtered off (5 g).
(c) To the crude intermediate was added 32 ml of a 15% aqueous HCl solution and the resulting suspension was heated at 90° C. for 3 hours. After cooling, the solid was filtered off and the acidic solution was taken to dryness to give 1.5 g of the hydrochloride of the title compound as a pinkish solid. M.p. >280° C. [0098]
Description 5 [0099]
N-[2-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl]-acetamide [0100]
To a cooled solution of NaOH (0.41 g, 10 mmoles) in water (5 ml) were simultaneously added 1-(2-aminoethyl)-1,3-dihydro-2H-benzimidazol-2-one hydrochloride (0.7 g, 3.3 mmoles) and a solution of acetic anhydride (0.37 ml, 3.9 mmoles) in dioxane (10 ml). The reaction mixture was stirred for 2 hours at room temperature and then taken to dryness. The residue was dissolved in water, adjusted to pH 4 with 10% aqueous HCl, and extracted with CHCl[0101] ₃. The organic layer was taken to dryness and from the crude residue 0.35 g of the title compound was obtained after crystallization from diethyl ether. M.p. 153° C.
Description 6 [0102]
N-[2-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl]methanesulfonamide [0103]
To a solution of 1-(2-aminoethyl)-1,3-dihydro-2H-benzimidazol-2-one hydrochloride (2.8 g, 13 mmoles) in THF (30 ml) and triethyl amine (5.5 ml, 39 mmoles) was added methanesulfonyl chloride (1.12 ml, 14 mmoles) and the reaction mixture was stirred for 2 hours at room temperature. The organic solvent was evaporated and the residue was partitioned into water and ethyl acetate. The organic layer was washed with saturated aqueous Na[0104] ₂CO₃solution and taken to dryness. The crude residue was purified by flash chromatography (CH₂Cl₂-methanol 96-4) to give 0.5 g of the title compound as a white solid. M.p. 162-170° C.
Description 7 [0105]
1-(2-chloroethyl)-3-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0106]
Into a stirred solution of 1-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one (6.5 g, 25 mmoles) in DMF (40 ml) 80% sodium hydride (0.9 g, 30 mmoles) was added. After 30 minutes of stirring and heating to 35° C., 1-bromo-2-chloroethane (6.2 g, 48 mmoles) was added, the reaction temperature was increased to 90° C. and kept for 6 hours then cooled at room temperature. The reaction mixture was poured into water, extracted with diethyl ether, and the organic layer was taken to dryness. The residue was purified by flash chromatography (cyclohexane-ethyl acetate 50-50) to give 2.8 g of the title compound as a thick oil which was used without any further purification. [0107]
According to the above described procedure, the following compounds were prepared from the suitable intermediates: [0108]
1-(4-chlorobutyl)-3-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0109]
The compound was purified by flash chromatography (cyclohexane-ethyl acetate 50-50). Thick oil. [0110]
[BB01]: 1-(2-chloroethyl)-3-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0111]
White solid. M.p. 55° C., from diisopropyl ether. [0112]
[BB01]: 1-(4-chlorobutyl)-3-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0113]
The compound was purified by flash chromatography (cyclohexane-ethyl acetate 50-50). Thick oil. [0114]
[BB15]: 1-[(2Z)-4-chloro-2butenyl)]-3-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0115]
The compound was purified by flash chromatography (cyclohexane-ethyl acetate 70-30). Thick oil. [0116]
[BB24]: N-{2-[3-(2-chloroethyl)-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl}-acetamide [0117]
White solid. M.p. 140° C.-142° C., from acetone. [0118]
[BB06]: N-{2-[3-(4-chlorobutyl)-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl}-acetamide [0119]
Ivory solid. M.p. 100° C., from diethyl ether. [0120]
Description 8 [0121]
1-[(2Z)-4-chloro-2-butenyl]-3-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0122]
To a solution of 1-[2-(tetrahydro-2H-pyran-2yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one (12 g, 46 mmoles) in DMF (120 ml) was added 80% sodium hydride (1.7 g, 55 mmoles) and the mixture was stirred at room temperature for 1 hour. Cis-1,4-dichloro-2-butene (5.8 ml, 55 mmoles) was added dropwise and the reaction mixture was stirred for 3 hours at room temperature. The reaction mixture was poured into water and extracted with ethyl acetate. The organic layer was taken to dryness and the residue was purified by flash chromatography (cyclohexane-ethyl acetate 70-30) to give 2.8 g of the title compound as a thick oil which was used without any further purification. [0123]
According to the above described procedure, the following compounds were prepared from the suitable intermediates: [0124]
1-[(2E)-4-chloro-2-butenyl)]-3-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0125]
The compound was purified by flash chromatography (cyclohexane-ethyl acetate 70-30). Waxy solid. [0126]
[BB16]: 1-[(2E)-4-chloro-2-butenyl)]-3-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0127]
The compound was purified by flash chromatography (cyclohexane-ethyl acetate 70-30). Thick oil. [0128]
[BB25]: N-(2-{3-[(2Z)-4-chloro-2-butenyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]}ethyl)-acetamide [0129]
The compound was purified by flash chromatography (CH[0130] ₂Cl₂-methanol 97-3). Waxy solid from diisopropyl ether, m.p. 118° C.
[BB26]: N-(2-{3-[(2E)-4-chloro-2-butenyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]}ethyl)-acetamide [0131]
White solid from diethyl ether, m.p. 108° C. [0132]
[BB13]: N-{2-[3-(2-chloroethyl)-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl}methanesulfonamide [0133]
The compound was purified by flash chromatography (CH[0134] ₂Cl₂-methanol 98-2). White low melting solid.
[BB07]: N-{2-[3-(4-chlorobutyl)-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl}methanesulfonamide [0135]
White solid, m.p. 104° C. from diethyl ether. [0136]
[BB27]: N-(2-{3-[(2Z)-4-chloro-2-butenyl)]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl}methanesulfonamide [0137]
The compound was purified by flash chromatography (CH[0138] ₂Cl₂-methanol 97-3). White solid, m.p. 83° C. from diethyl ether.
[BB28]: N-2-{3-[(2E)-4-chloro-2butenyl)]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl}methanesulfonamide [0139]
The compound was purified by flash chromatography (CH[0140] ₂Cl₂-methanol 98-2). White solid, m.p. 98° C. from diethyl ether.
Description 9 [0141]
[BB08]: 1-(2-chloroethyl)-3-[(2-piperidinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0142]
A solution of 1-[2-(1-piperidinyl)ethyl)-1,3-dihydro-2H-benzimidazol-2-one (4 g, 16.3 mmoles) in DMF (50 ml) was added to a suspension of 80% sodium hydride (0.49 g, 16.3 mmoles) in DMF (25 ml) and the reaction mixture was heated under stirring for 30 minutes at 40° C. The solution was slowly transferred (3 hours) into a solution of 1-bromo-2-chloroethane (2.7 ml, 32.6 mmoles) in DMF (30 ml), the temperature was increased to 60° C. and stirred for 5 hours. The reaction mixture was then taken to dryness under vacuum, and the residue partitioned between 5% aqueous HCl and diethyl ether. The aqueous layer was adjusted to pH 9 to 10 with sodium carbonate and extracted with ethyl acetate. After evaporation and flash chromatography purification (CH[0143] ₂Cl₂-methanol-NH₄OH 95-5-0.5), 2.2 g of the pure title compound was obtained as a clear oil.
According to the above described procedure, the following compounds were prepared from the suitable intermediates: [0144]
[BB02]: 1-(4-chlorobutyl)-3-[(2-(1-piperidinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0145]
The compound was purified by flash chromatography (CH[0146] ₂Cl₂-methanol-NH₄OH 95-5-0.5). Ivory solid, m.p. 82° C.-87° C. from diethyl ether.
[BB12]: 1-(2-chloroethyl)-3-[2-(4-morpholinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0147]
The compound was purified by flash chromatography (CH[0148] ₂Cl₂-methanol-NH₄OH 95-5-0.5). Thick oil.
[BB03]: 1-(4-chlorobutyl)-3-[2-(4-morpholinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0149]
The compound was purified by flash chromatography (CH[0150] ₂Cl₂-methanol-NH₄OH 95-5-0.5). Clear oil.
Description 10 [0151]
[BB14]: 1-[(2Z)-4-chloro-2-butenyl)]-3-[2-(4-morpholinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0152]
A solution of 1-[2-(4-morpholinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one (4 g, 16.2 mmoles) in DMF (50 ml) was added dropwise to a suspension of 80% sodium hydride (0.49 g, 16.2 mmoles) in DMF (50 ml) and the mixture was heated under stirring at 45° C. for 30 minutes. This solution was slowly transferred (4 hours) to a solution of cis-1,4-dichloro-2-butene (3.43 ml, 32.4 mmoles) in DMF (20 ml). The reaction mixture was stirred overnight at room temperature, taken to dryness under vacuum, and partitioned between ethyl acetate and water. From the organic solution after evaporation and flash chromatography purification (CH[0153] ₂Cl₂-methanol-NH4OH 95-5-0.5), 2.4 g of the title compound were obtained as an oil.
According to the above described procedure, the following compounds were prepared from the suitable intermediates: [0154]
[BB19]: 1-[(2E)-4-chloro-2-butenyl]-3-[2-(4-morpholinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0155]
The compound was purified by flash chromatography (CH[0156] ₂Cl₂-methanol-NH₄OH 95-5-0.5). Thick oil.
[BB17]: 1-[(2Z)-4-chloro-2-butenyl]-3-[2-(1-piperidinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0157]
The compound was purified by flash chromatography (CH[0158] ₂Cl₂-methanol-NH₄OH 95-5-0.5). Thick oil.
[BB18]: 1-[(2E)-4-chloro-2-butenyl]-3-[2-(1-piperidinyl)ethyl]-1,3-dihydro-2H-benzimidazol-2-one [0159]
The compound was purified by flash chromatography (CH[0160] ₂Cl₂-methanol-NH₄OH 95-5-0.5). Thick oil.
Description 11 [0161]
[BB10]: 1-(2-chloroethyl)-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0162]
A solution of 1-(2-chloroethyl)-3-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1,3-dihydro-2H-benzimidazol-2-one (2.2 g) and a catalytic amount of p-toluenesulfonic acid (0.1 g) in methanol (30 ml) was stirred at room temperature for 2 hours. The reaction mixture was evaporated to dryness, the residue was dissolved in CH[0163] ₂Cl₂and washed with a saturated aqueous solution of K₂CO₃. The organic layer was taken to dryness to give 1.5 g of the title compound as white solid. M.p. 135° C.
According to the above described procedure, the following compounds were prepared from the suitable intermediates: [0164]
[BB04]: 1-(4-chlorobutyl)-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0165]
Thick oil. [0166]
[BB20]: 1-[(2Z)-4-chloro-2-butenyl]-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0167]
White solid, m.p. 80° C. from diethyl ether. [0168]
[BB21]: 1-[(2E)-4-chloro-2-butenyl]-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one [0169]
Ivory solid, m.p. 73° C. from diethyl ether. [0170]
Description 12 [0171]
[BB11]: 2-[3-(2-chloroethyl)-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl-ethylcarbamate [0172]
1-(2-chloroethyl)-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one (2.6 g, 11 mmoles) and ethyl isocyanate (20 ml) were refluxed under stirring for 6 hours then left overnight at room temperature. The reaction mixture was taken to dryness and the residue was crystallized from diisopropyl ether to give 3 g of the title compound. M.p. 125° C. [0173]
According to the above described procedure, the following compound was prepared from the suitable intermediate: [0174]
[BB05]: 2-[3-(4-chlorobutyl)-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl-ethylcarbamate [0175]
White solid, m.p. 75° C. from diethyl ether. [0176]
Description 13 [0177]
[BB22]: 2-{3-[(2Z)-4-chloro-2-butenyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl]ethyl-ethylcarbamate [0178]
1-(4-chlorobutyl)-3-(2-hydroxyethyl)-1,3-dihydro-2H-benzimidazol-2-one (1.8 g, 6.8 mmoles) and ethyl isocyanate (6 ml) were stirred at room temperature for 48 hours. The reaction mixture was then taken to dryness and the residue was crystallized from diethyl ether to give 1.8 g the title compound. M.p. 107° C. [0179]
According to the above described procedure, the following compound was prepared from the suitable intermediate: [0180]
[BB23]: 2-{3-[(2E)-4-chloro-2-butenyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl}ethyl-ethylcarbamate [0181]
The compound was purified by flash chromatography (cyclohexane-ethyl acetate 50-50). White solid, m.p. 70° C. from diethyl ether. [0182]
B. General Method for the Preparation of the Compounds of Formula (I) [0183]
A solution of each building block of formula (II) (0.1 mM) was reacted under stirring with each amine (0.2 mM) in anhydrous DMF (100 μl) in the presence of Na[0184] ₂CO₃(0.3 mM) at a temperature ranging from room temperature to 100° C., preferably between 60° C. and 80° C., for about 6 to 8 hours. Isocyanatemethyl Polystyrene Resin (loading 0.23 meq/g) (0.2 mM) was introduced and the mixture was gently stirred at room temperature for 8 hours. The resin was then filtered off under vacuum, washed with DMF, and filtered again. The collected solutions were evaporated to dryness in a speed-vac centrifuge. The compounds which were prepared according to the above described procedure are listed in Table 3.

Table 3 collects the structural formula of the synthesized compounds along with the corresponding characterizing mass data (i.e., [M+H] ⁺) obtained for each of the compounds according to the invention. The identification of the compounds and their purity was carried out by using positive APCI-LC/MS technique.

TABLE 3


Compounds of Formula (I)

(I)


Compound No.	—R¹	—A—	[M + H]⁺


1				409

2				533

3				423

4				410

5				443

6				411

7				419

8				478

9				477

10				406

11				477

12				464

13				526

14				439

15				457

16				478

17				467

18				437

19				439

20				462

21				586

22				476

23				463

24				496

25				464

26				472

27				531

28				530

29				459

30				530

31				517

32				579

33				492

34				510

35				531

36				520

37				490

38				492

39				464

40				588

41				478

42				465

43				498

44				466

45				474

46				533

47				532

48				461

49				532

50				519

51				581

52				494

53				512

54				533

55				522

56				395

57				419

58				409

59				396

60				429

61				397

62				405

63				464

64				463

65				392

66				463

67				450

68				512

69				425

70				443

71				464

72				453

73				423

74				425

75				466

76				590

77				480

78				467

79				500

80				468

81				476

82				535

83				534

84				463

85				534

86				521

87				583

88				496

89				514

90				535

91				524

92				494

93				496

94				480

95				480

96				500

97				436

98				560

99				450

100				437

101				470

102				438

103				446

104				505

105				504

106				433

107				504

108				491

109				553

110				466

111				484

112				505

113				494

114				464

115				466

116				450

117				450

118				470

119				472

120				596

121				486

122				473

123				506

124				474

125				482

126				541

127				540

128				469

129				540

130				527

131				589

132				502

133				520

134				541

135				530

136				500

137				502

138				486

139				486

140				506

141				434

142				558

143				448

144				435

145				468

146				436

147				444

148				503

149				502

150				431

151				502

152				489

153				551

154				464

155				482

156				503

157				492

158				462

159				464

160				381

161				505

162				395

163				382

164				415

165				383

166				391

167				450

168				449

169				378

170				449

171				436

172				526

173				411

174				429

175				450

176				450

177				409

178				411

179				367

180				491

181				381

182				368

183				401

184				369

185				377

186				436

187				435

188				364

189				435

190				422

191				484

192				397

193				415

194				436

195				436

196				395

197				397

198				438

199				562

200				452

201				439

202				472

203				440

204				448

205				507

206				506

207				435

208				506

209				493

210				555

211				468

212				486

213				507

214				496

215				466

216				468

217				452

218				452

219				472

220				436

221				560

222				450

223				437

224				470

225				438

226				446

227				533

228				504

229				433

230				504

231				491

232				553

233				466

234				484

235				505

236				494

237				444

238				568

239				458

240				445

241				478

242				446

243				454

244				513

245				512

246				441

247				512

248				499

249				561

250				474

251				492

252				513

253				502

254				472

255				474

256				458

257				458

258				478

259				462

260				586

261				476

262				463

263				496

264				464

265				472

266				531

267				530

268				459

269				530

270				517

271				579

272				492

273				510

274				531

275				520

276				407

277				531

278				421

279				408

280				441

281				409

282				417

283				476

284				475

285				404

286				475

287				462

288				524

289				437

290				455

291				476

292				465

293				407

294				531

295				421

296				408

297				441

298				409

299				417

300				432

301				475

302				404

303				475

304				462

305				524

306				437

307				455

308				476

309				465

310				460

311				584

312				474

313				461

314				694

315				462

316				470

317				465

318				528

319				457

320				528

321				515

322				577

323				490

324				508

325				529

326				518

327				460

328				584

329				474

330				461

331				494

332				462

333				470

334				465

335				528

336				457

337				528

338				515

339				577

340				490

341				508

342				529

343				518

344				462

345				586

346				476

347				463

348				496

349				464

350				472

351				467

352				530

353				459

354				530

355				517

356				579

357				492

358				510

359				531

360				520

361				393

362				517

363				407

364				394

365				427

366				395

367				403

368				476

369				461

370				390

371				461

372				448

373				510

374				423

375				441

376				462

377				451

378				393

379				517

380				407

381				394

382				427

383				395

384				403

385				476

386				461

387				390

388				461

389				448

390				510

391				423

392				441

393				462

394				451

395				464

396				588

397				478

398				465

399				699

400				466

401				474

402				469

403				532

404				461

405				532

406				519

407				581

408				494

409				512

410				533

411				522

412				464

413				588

414				478

415				465

416				498

417				466

418				474

419				469

420				532

421				461

422				532

423				519

424				581

425				494

426				512

427				533

428				522

429				408

430				532

431				422

432				409

433				442

434				410

435				418

436				477

437				476

438				405

439				476

440				463

441				525

442				438

443				456

444				477

445				466

446				436

447				438

448				422

449				422

450				442

451				434

452				558

453				448

454				435

455				468

456				436

457				444

458				503

459				502

460				431

461				502

462				489

463				551

464				464

465				482

466				503

467				492

468				462

469				464

470				448

471				448

472				468

473				434

474				558

475				448

476				435

477				468

478				436

479				444

480				503

481				502

482				431

483				502

484				489

485				551

486				464

487				482

488				503

489				492

490				462

491				464

492				448

493				448

494				468

495				470

496				594

497				484

498				471

499				504

500				472

501				480

502				539

503				538

504				467

505				538

506				525

507				587

508				500

509				518

510				539

511				528

512				498

513				500

514				484

515				484

516				504

517				470

518				594

519				484

520				471

521				504

522				472

523				480

524				539

525				538

526				467

527				538

528				525

529				587

530				500

531				518

532				539

533				528

534				498

535				500

536				484

537				484

538				504

The biological profile of the compounds of the invention, was assessed by evaluating their activity at the 5-HT[0186] _1A, 5-HT_2A, and D₄receptors, according to the methods described below.
Receptor Binding Studies [0187]
Receptor binding studies were carried out to determine the affinity of the compounds for 5-HT[0188] _1A, 5-HT_2A, and D₄receptors
5-HT[0189] _1ARadioligand Receptor Binding Assay
Membranes from CHO cells, expressing 5-HT[0190] _1Ahuman receptors were suspended in incubation buffer.
Binding Assay: [0191]
Binding assays were performed in MultiProbe 204 pipetting system (Packard), according to a predetermined mapping, consistent with the software Screen. The compounds were tested in singlicate at one concentration (10[0192] ⁻¹M) in a total volume of 1000 μl. 980 μl of diluted membranes, 10 μl DMSO or unlabelled ligand and 10 μl of [³H]-8-OH-DPAT (0.6-0.7 nM) were incubated for 60 minutes at 27° C. The reaction was stopped by rapid filtration through Tomtec Cell Harvester (48 wells) using Filtermat B (presoaked in 0.1% PEI) filters. Filters were washed with ice-cold 50 mM Tris-HCl (pH 7.4) buffer (9×700 μl), dried, covered with MeltiLex B/HS scintillator sheets (Wallac) and heated at 80° C. to 90° C. for about 10 minutes, transferred into plastic sample bags (Wallac), sealed, and put into 1024 Beta Plate scintillation counter (Wallac). Non-specific binding was determined in the presence of 5-HT (10⁻⁵M).
Data Analysis: [0193]
The specific radioligand binding to the receptor was defined by the difference between total binding and non-specific binding, determined in the presence of an excess of unlabelled ligand. Results were expressed as percentage of control specific binding obtained in the presence of the compounds. The affinity values (IC[0194] ₅₀) for the compounds were obtained by a nonlinear least squares regression analysis on the basis of a one binding site model.
5-HT[0195] _1AFunctional Assay (cAMP)
CHO/5-HT[0196] _1Acells were random seeded at a density of about 200,000/well in 24 well plates the day prior to the experiment. On the day of the experiment, cells were pretreated for 15 minutes at 37° C. with 500 μM isobutylmethylxantine (IBMX) dissolved in culture medium without serum. Wells were then divided in different groups in duplicate as follows: control, 10 μM FSK, 10 μM FSK+1 μM 5-HT as positive standard and 10 μM FSK+10 μM of the different compound under evaluation. Sample solutions were added and incubated for additional 15 minutes at 37° C. After incubation, the medium was aspirated and the reaction stopped by adding 200 μl of lysis buffer. Plates were shaken for 5 minutes, then the lysate was removed and samples were stored at 4° C. until the day of the assay. For the cAMP evaluation, samples were properly diluted and the cAMP content was measured by an enzyme immunoassay system.
Data Analysis: [0197]
Results are expressed as % inhibition of the cAMP accumulation induced by 10 μM FSK. [0198]
D[0199] ₄Radioligand Receptor Binding Assay
Membranes from CHO cells expressing D[0200] ₄human receptors, were suspended in incubation buffer.
Binding Assay: [0201]
Binding assays were performed in MultiProbe 204 pipetting system (Packard), according to a predetermined mapping, consistent with the software Screen. The compounds were tested in singlicate at one concentration (10[0202] ⁻⁷M) in a total volume of 1000 μl (980 μl of diluted membranes, 10 μl DMSO or unlabelled ligand and 10 μl of [³H] YM-09151-2 (0.15-0.25 nM). After incubation for 120 minutes at 27° C., the reaction was stopped by rapid filtration through Tomtec Cell Harvester (48 wells) using Filtermat B (presoaked in 0.1% PEI) filters. Filters were washed with ice-cold 50 mM Tris-HCl (pH 7.4) buffer (9×700 μl), dried, covered with MeltiLex B/HS (Wallac) scintillator sheets and heated in oven at 80° C. to 90° C. for about 10 minutes, transferred into plastic sample bags (Wallac), sealed, and put into 1024 Beta Plate scintillation counter (Wallac). Non-specific binding was determined in the presence of clozapine dissolved in DMSO to a final concentration of 10⁻⁵M.
Data Analysis: [0203]
The specific radioligand binding to the receptor was defined by the difference between total binding and non-specific binding, determined in the presence of an excess of unlabelled ligand. Results were expressed as percentage of control specific binding obtained in the presence of the compounds. [0204]
5-HT[0205] _2ARadioligand Receptor Binding Assay
Tissue Preparation: [0206]
Rats (male Sprague-Dawley, 200-250 g) were used. Cerebral frontal cortex was homogenized in 10 volumes of ice cold 0.32 M sucrose in 5 mM Tris-HCl (pH 74) buffer. After centrifugation of the homogenate (1,000×g for 10 minutes) the supernatant was then recentrifuged at 48,000×g for 15 minutes. The resulting pellet was gently homogenized in an equal volume of 50 mM Tris-HCl buffer (pH 7.4) and incubated at 37° C. for 10 minutes. Membranes were then collected by centrifugation as above described and finally resuspended in 10 volumes of 50 mM Tris-HCl buffer (pH 7.4). [0207]
Binding Assay: [0208]
For displacement experiments membranes (980 μl) were diluted in 50 mM Tris-HCl buffer (pH 7.4) to a final concentration of 1:100 (w/v); the tissue suspension was then incubated at 37° C. for 10 minutes in a final volume of 1 ml in the presence of 0.5 nM [[0209] ³H]-Ketanserin. Non-specific binding was determined by incubating similar samples with unlabelled methysergide (100 μM). After incubation, samples prepared in a 24 wells cell culture cluster (Costar) were rapidly filtered by Inotech Cell Harvester (IH 201 filters). The filters were washed three times with 2 ml ice-cold Tris-HCl buffer and placed in polyethylene vials, then 4 ml of Filter Count scintillation cocktail (Packard) were added. The radioactivity present was counted by liquid scintillation spectrometry.
Data Analysis: [0210]
The affinity values (IC[0211] ₅₀) for the compounds were obtained by a nonlinear least squares regression analysis on the basis of a one binding site model.
5-HT[0212] _2AFunctional Assay (PI turnover)
Tissue Preparation: [0213]
Cross-chopped miniprisms (350×350 μm) were prepared from mouse whole cerebral cortices and incubated for 60 minutes at 37° C. in Krebs-Henseleit buffer containing 2 g/l glucose. [0214]
Functional Assay: [0215]
Cerebral cortex miniprisms were distributed in vials and incubated for 30 minutes with approximately 170 nM [[0216] ³H]-myoinositol (10-20 Ci/mmol) and 10 mM lithium chloride. Samples were divided in different groups in triplicate: control, 100 μM 5-HT, 10 and 30 μM flibanserin+100 μM 5-HT, as standards, and 10 μM of the different compound under investigation+100 μM 5-HT. When 5-HT was added the incubation continued for 45 minutes. Compounds under investigation and flibanserin were added 10 minutes before dispensing 5-HT. Incubation was terminated by the addition of 940 μl chloroform-methanol (1:2 v/v). Further aliquots of chloroform (310 μl) and water (310 μl) were added and labeled inositol phosphates (1 Ps) were extracted from the aqueous phase by ion exchange chromatography using Dowex resin in the formate form. After addition of 10 ml of PicoFluor 40 scintillation cocktail (Packard), the radioactivity present in an aliquot (400 μl) of the aqueous extract was counted by liquid scintillation spectrometry.
Data Analysis: [0217]
Results are expressed as % inhibition of the PI turnover accumulation induced by 100 μM 5-HT. [0218]

The following Tables 4 to 6 collect the biological data at the receptors of the new compounds.

TABLE 4


% Inhibition at 5-HT_1Aand D₄Receptors

	5-HT_1AReceptor	D₄Receptor		5-HT_1AReceptor	D₄Receptor
	Binding Assay	Binding Assay		Binding Assay	Binding Assay
Comp.	% inhibition	% inhibition	Comp.	% inhibition	% inhibition
No.	(10⁻⁷M)	(10⁻⁷M)	No.	(10⁻⁷M)	(10⁻⁷M)

1	56	38	78	69	44
5	92	54	79	86	58
7	77	91	81	55	78
9	93	32	83	89	39
10	60	47	84	52	42
11	48	90	85	77	79
19	69	32	92	94	55
20	50	60	93	94	62
23	73	48	94	88	72
24	90	67	95	85	64
25	48	44	96	92	72
26	70	94	107	55	58
28	89	35	118	80	36
29	57	83	145	85	42
30	44	90	149	88	35
37	90	54	150	57	52
38	92	78	158	95	72
39	36	42	159	85	50
43	104	55	164	96	41
45	100	82	169	85	58
56	63	71	177	98	39
59	75	51	182	62	45
60	93	82	183	96	62
62	73	96	187	94	36
64	92	43	188	78	78
65	52	74	189	54	99
66	65	99	197	77	43
73	91	58	215	98	48
74	92	62	216	92	44
75	67	54	219	89	37
224	98	51	332	78	85
226	71	32	333	99	80
228	95	33	335	95	55
229	67	34	336	90	81
241	69	32	348	99	51
254	85	34	349	73	31
255	58	33	361	86	46
256	59	51	364	77	36
263	92	42	365	89	63
265	55	78	367	61	90
280	93	38	369	96	59

TABLE 5


5-HT_1AAgonist Activity

5-HT_1A

	Receptor Binding	cAMP
Compound No.	IC₅₀(nM)	% inhibition

5	13	63
9	9.9	48
37	16	44
60	6.2	65
64	12	52
73	13	45
83	15	64
158	13	48
164	4.2	73
168	5.0	71
177	3.3	76
183	7.2	66
187	8.2	44
202	1.7	72
206	2.1	80
215	0.85	83
217	5.2	68
219	15	61
228	6.0	82
254	7.4	66
263	8.8	63
284	4.9	82
285	5.2	47
296	8.2	82
297	7.9	74
301	2.6	83
310	15	63
314	7.1	44
318	3.1	61
330	7.9	62
333	16	67
335	3.5	69
347	13	65
348	3.5	57
352	4.1	79
365	15	82
369	3.5	84
370	4.4	52
381	44	79
382	11	64
386	6.7	82
403	5.5	84
404	2.1	60
415	14	82
416	7.9	77
420	1.8	87
421	0.66	56
446	7.3	81
459	8.8	86
468	3.1	66
472	3.1	67
481	11	82
499	5.0	74
503	2.8	87
504	3.6	50
512	0.59	68
514	7.9	67
520	8.1	70
521	0.61	67
525	1.5	87
536	9.5	55

[0221]

TABLE 6

5-HT_2AAntagonist Activity

5-HT_2A

Receptor

Binding PI Turnover

Compound No. IC₅₀(nM) % inhibition

9 16 45

73 0.90 42

83 43 86

168 46 22.00

177 7.7 39

183 27 12.00

206 17 90

215 3.2 83

254 65 64

514 74 41

521 30 48

Claims

We claim:

1. A compound of formula (I)

wherein:

A is C₁-C₆-alkylene, C₂-C₆-alkenylene, or C₂-C₆-alkynylene,

or a pharmaceutically acceptable salt thereof.

2. The compound of formula (I) according to claim 1, wherein:

R¹is C₁-C₄-alkyl substituted by a group selected from OH, C₁-C₄-alkoxy, —OCONHC₁-C₄-alkyl, —OCONHC₁-C₄-alkyl, —NHSO₂C₁-C₄-alkyl, and —NHCOC₁-C₄-alkyl, or

R¹is C₁-C₄-alkyl substituted by a saturated or unsaturated 6-membered heterocycle containing one or two heteroatoms selected from the group consisting of nitrogen and oxygen;

R²and R³together with the nitrogen form a saturated or unsaturated 5- or 6-membered heterocyclic ring optionally containing nitrogen as an additional heteroatom, the heterocyclic ring thereof substituted by a group selected from phenyl, benzyl, diphenylmethyl, pyridinyl, pyrimidinyl, benzimidazolonyl, and 3,4-methylenedioxibenzyl, each of these groups optionally mono- or di-substituted by a group selected from CF₃, C₁-C₄-alkyl, C₁-C₄-alkoxy, halogen, and OH; and

A is C₁-C₄-alkylene or C₂-C₄-alkenylene,

or a pharmaceutically acceptable salt thereof.

3. The compound of formula (I) according to claim 1, wherein:

R¹is ethyl substituted by a group selected from OH, OCH₃, OCH₂CH₃, —OCONHCH₃, —OCONHCH₂CH₃, —NHSO₂CH₃, —NHSO₂CH₂CH₃, —NHCOCH₃, —NHCOCH₂CH₃, morpholinyl, piperazinyl, and piperidinyl;

R²and R³together with the nitrogen form a 6-membered saturated or unsaturated heterocyclic ring optionally containing nitrogen as an additional heteroatom, the heterocyclic ring thereof substituted by a group selected from phenyl, pyridinyl, pyrimidinyl, benzimidizalonyl, and phenyl mono- or di-substituted by a group selected from CF₃, CH₃, OCH₃, F, and Cl;

A is C₁-C₄-alkylene or C₂-C₄-alkenylene,

or a pharmaceutically acceptable salt thereof.

4. The compound of formula (I) according to claim 1, wherein:

R¹is ethyl substituted by a group selected from OH, OCH₃, —OCONHCH₂CH₃, —NHSO₂CH₃, —NHCOCH₃, morpholinyl, and piperidinyl;

R²and R³together with the nitrogen form a 6-membered saturated or unsaturated heterocyclic ring optionally containing nitrogen as an additional heteroatom, the heterocyclic ring thereof substituted by a group selected from pyridinyl, phenyl, and phenyl mono- or di-substituted by a group selected from CF₃, CH₃, OCH₃, F, and Cl; and

A is ethylene, propylene, butylene, or butenylene,

or a pharmaceutically acceptable salt thereof.

5. The compound of formula (I) according to claim 1, wherein:

R¹is ethyl substituted by a group selected from OH, OCH₃, —OCONHCH₂CH₃, —NHSO₂CH₃, —NHCOCH₃, morpholinyl, and piperidinyl

R²and R³together with the nitrogen form a heterocyclic ring selected from the group consisting of piperazine, piperidine, and tetrahydropyridine, the heterocyclic ring thereof substituted by a group selected from pyridinyl, phenyl, and phenyl mono- or di-substituted by a group selected from CF₃, CH₃, and Cl; and

A is ethylene, butylene, or butenylene,

or a pharmaceutically acceptable salt thereof.

6. The compound of formula (I) according to claim 1, wherein:

R¹is ethyl substituted by a group selected from OH, OCH₃, —OCONHCH₂CH₃, and —NHSO₂CH₃;

R¹and R³together with the nitrogen form a piperazine ring, the piperazine ring thereof substituted by a group selected from trifluoromethylphenyl, methylphenyl, dimethylphenyl, and chlorophenyl; and

A is ethylene, butylene, or butenylene,

or a pharmaceutically acceptable salt thereof.

7. The compound of formula (I) according to claim 1, wherein R¹is a C₁-C₄-alkyl group.

8. The compound of formula (I) according to claim 1, wherein A is C₁-C₄-alkylene, C₂-C₄-alkenylene, or C₂-C₄-alkynylene.

9. A compound selected from the group consisting of:

(e) 1-{[2-[4-(2,3-dimethylphenyl)-1-piperazinyl]ethyl}-3-(2-methoxyethyl)-1,3-dihydro-2H-benzimidazol-2-one;

(k) N-[2-(3-{(2E)-4-[4-(3-chlorophenyl)-1-piperazinyl]-2-butenyl}-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)ethyl]methanesulfonamide,

or a pharmaceutically acceptable salt thereof.

10. A pharmaceutical composition comprising an effective amount of a compound of formula (I) according to one of claims 1 to 9 and a pharmaceutical carrier, diluent, or excipient.

11. A method for treatment or prophylaxis of anxiety disorders and affective disorders, in a host in need of such treatment or prophylaxis, which method comprises administering the host an effective amount of a compound according to one of claims 1 to 9.

12. A method for treatment or prophylaxis of treatment of a disease selected from the group consisting of depression, psychosis, schizophrenia, eating disorders, sexual disorders, Parkinson's disease, and stroke and traumatic brain injury, in a host in need of such treatment or prophylaxis, which method comprises administering the host an effective amount of a compound according to one of claims 1 to 9.