KR20000068255A - Troponyl piperazines as selective dopamine D4 receptor ligands - Google Patents

Abstract

Described herein are compounds of formula (I), stereoisomers, solvates or pharmaceutically acceptable salts thereof.

Formula I

In the above formula,

R ₁ is H; Halo; Aryl; Or aryl substituted with one or two groups independently selected from halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy or cyano,

R ₂ is C _4-9 alkyl; Phenyl or phenyl substituted with one or two groups independently selected from OH, cyano, halo, C _1-4 alkoxy, C _1-4 alkyl, trifluoromethyl, trifluoromethoxy, nitro or phenyl; Naphthyl; Phenyl fused to a 5 or 6 membered heterocycle; Coumarin residues Wherein R ₃ and R ₄ are independently selected from H, C _1-4 alkyl and C _1-4 alkoxy; Or 1,2-methylenedioxy phenyl,

Provided that when R ₁ is H, R ₂ is not phenyl or 3,4-dimethoxyphenyl.

Also described is its use as a medicament for treating diseases associated with dopamine D4 receptors, such as schizophrenia and anxiety.

Description

Troponyl piperazines as selective dopamine D4 receptor ligands

The present invention relates to compounds that bind to dopamine D4 receptor, methods for their preparation, and their use for therapeutic and drug screening purposes.

Neuronal receptors that bind the neurotransmitter dopamine constitute five or more structurally different protein groups that can now be produced using recombinant DNA technology. These techniques have been applied to construct cell lines incorporating dopamine receptors into their membranes, providing a renewable and homogeneous material that allows the selection of chemical libraries to identify potential CNS-active agents.

Recent evidence strongly relates to dopamine receptors that are classified as D4 in the pathogenesis of schizophrenia. It has been suggested that compounds that could interfere with the action of these receptors present in a cleaved state at levels six times normal would be useful for the treatment of these diseases. Seeman et al, Nature, 1993, 365: 441 ]. Some drugs currently on the market actually exhibit the desired antagonism of D4 receptor activity and bind to the receptor with relatively strong affinity. However, because of their structure, these agents also interact with related dopamine receptors, especially the D2 receptor type, resulting in marked side effects including modified locomotor action and rash. It may be desirable to provide compounds that exhibit a high degree of affinity for the D4 receptor as well as a relatively low degree of affinity for the D2 receptor. This desired combination of receptor binding properties is referred to herein as D4 selectivity.

Current products for the treatment of symptoms involving D4 receptor action include dibenzodiazepine, clozapine and dibenzoxazepine, isoxroxapin. Analysis of their dopamine receptor binding properties indicated that the binding of the D4 receptor to the D2 receptor was about 10-fold preferred for both products. Similarly, the two products bind to the D4 receptor with almost the same affinity (K _i value about 20 nM). Other products recently published in scientific books exhibit D4 selectivity profiles and D4 affinity values similar to D2.

For example, the use of certain troponyl piperazines as dopamine receptor agonists for treating Parkinson's disease and other related diseases is described in EP 034,894 and related scientific literature Bagli, J. et al. J. Med. Chem. 1984, 27: 875 and Bagli, J. et al., J. Med. Chem. 1986, 29: 186.

It is an object of the present invention to provide compounds which bind to the D4 receptor.

It is an object of the present invention to provide a D4 receptor-binding compound.

Another object of the present invention is to provide compounds which bind specifically to the D4 receptor, in particular over the D2 receptor.

A further object of the present invention is to provide a pharmaceutical composition comprising the compound of the present invention as an active ingredient.

It is another object of the present invention to provide an effective method for treating a medical disease such as schizophrenia and anxiety, which requires administration of a D4 receptor antagonist.

Summary of the Invention

According to one embodiment of the present invention, there is provided a compound of formula (I), a stereoisomer, solvate or pharmaceutically acceptable salt thereof.

In the above formula,

R ₁ is H; Halo; Aryl; Or aryl substituted with one or two groups independently selected from halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy or cyano,

R ₂ is C _4-9 alkyl; Phenyl or phenyl substituted with one or two groups independently selected from OH, cyano, halo, C _1-4 alkoxy, C _1-4 alkyl, trifluoromethyl, trifluoromethoxy, nitro or phenyl; Naphthyl; Phenyl fused to a 5 or 6 membered heterocycle; Coumarin residues Wherein R ₃ and R ₄ are independently selected from H, C _1-4 alkyl and C _1-4 alkoxy) or 1,2-methylenedioxy phenyl,

Provided that when R ₁ is H, R ₂ is not phenyl or 3,4-dimethoxyphenyl.

According to another aspect of the invention, there is provided a pharmaceutical composition comprising an effective amount of a compound of formula (I) and formula (II) and a pharmaceutically acceptable carrier to antagonize D4 receptor stimulation.

In the above formula,

R ₁ is H; Halo; Aryl; And aryl substituted with one or two groups independently selected from H, halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy and cyano and ,

R ₅ is C _4-9 alkyl; Phenyl or phenyl substituted with one or two groups independently selected from OH, cyano, halo, C _1-4 alkoxy, C _1-4 alkyl, trifluoromethyl, trifluoromethoxy, nitro or phenyl; Naphthyl; Phenyl fused to a 5 or 6 membered heterocycle; Coumarin residues Wherein R ₃ and R ₄ are independently selected from H, C _1-4 alkyl and C _1-4 alkoxy; Or 1,2-methylenedioxy phenyl.

It is essentially formula (I) unless there is a clue. Formula II may be used as a pharmaceutical composition.

In another aspect thereof, the present invention provides the use of the compounds of formulas (I) and (II) as a D4 receptor antagonist for the treatment of a medical disease achieved by inhibiting D4 receptor antagonism, and in the treatment of schizophrenia and anxiety.

In a further aspect of the invention there is provided an assay method for distinguishing D4 receptors from other receptor types, in particular D2 receptors, in a population of receptors using the compounds of the invention. The above and other aspects of the present invention are described in more detail.

Detailed Description and Preferred Embodiments

Justice:

The term "C _4-9 alkyl" as used herein refers to straight chain alkyl radicals having 4 to 9 carbon atoms and branched chain alkyl radicals having 6 to 8 carbon atoms and includes pentyl, hexyl, 1-methylhexyl and the like.

As used herein, the term “C _1-4 alkyl” refers to straight chain alkyl radicals having 1 to 4 carbon atoms and branched alkyl radicals having 3 or 4 carbon atoms and is methyl, ethyl, propyl, 1-methylethyl, butyl, 1- Methylpropyl and the like. 1-methylethyl and 1-methylpropyl are also known as isopropyl and secondary-butyl, respectively.

As used herein, the term “C _1-4 alkoxy” refers to straight chain alkoxy radicals having 1 to 4 carbon atoms and branched alkoxy radicals having 3 or 4 carbon atoms and includes methoxy, ethoxy, 1-methylethoxy, propyloxy, Butoxy and the like.

The term "halo" as used herein refers to halides and includes fluoro, chloro, bromo and iodo.

As used herein, the term “heterocycle” refers to a 5 or 6 membered saturated or unsaturated ring, wherein the heterocycle contains 1 to 3 heteroatoms independently selected from nitrogen, oxygen and sulfur and 1, 3-dioxol, thiophene, furan, pyrrole, imidazole, pyrazole, pyrrolidine, pyrroline, imidazolidine, pyrazolidine, pyrazoline, pyran, pyridine, pyrazine, pyrimidine, pyridazine, pyridine Ferridine, piperazine, morpholine and the like. Thus, some examples of “phenyl fused to a five or six membered heterocycle” include benzothiophene, isobenzofuran, chromate, indole, isoindole, indazole, isoquinoline, quinoline, phthalazine, quinoxaline, Quinazoline, cinnoline, isochroman, chromman, indolin, isoindolin.

The term aryl, as used herein, contains one or two nitrogen atoms, one or two oxygen atoms, one nitrogen and one oxygen atom, one nitrogen and one sulfur atom, or one sulfur atom. A 5 or 6 membered carbocyclic unsaturated ring system which is an aromatic (e.g. phenyl) or heteroaromatic ring and comprises thiophene, furan, pyrrole, pyran, pyridine, pyrazine, pyrimidine, pyridazine, isothiazole, isoxazole , Pyrazoline and pyrazine. Such aryls may be substituted with one or two groups independently selected from halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy and cyano to suit their chemical structure. Can be. Preferably aryl is phenyl substituted with one substituent in its meta- or para position.

The term “pharmaceutically acceptable salts” means acid addition salts or basic addition salts that are suitable for the treatment of patients for the desired use.

"Pharmaceutically acceptable acid addition salts" are non-toxic organic or inorganic acid addition salts of the base compound of formula (I) or intermediates thereof. Illustrative inorganic acids that form suitable salts include acid metal salts such as hydrochloric acid, bromic acid, sulfuric acid and phosphoric acid, and sodium monohydrogen orthophosphate and potassium hydrogen sulfate. Illustrative organic acids that form suitable salts include mono-, di- and tricarboxylic acids. Examples of such acids are, for example, acetic acid, glycolic acid, lactic acid, pyruvic acid, malonic acid, succinic acid, glutaric acid, fumaric acid, malic acid, tartaric acid, citric acid, ascorbic acid, maleic acid, hydroxymaleic acid, benzoic acid, Hydroxybenzoic acid, phenylacetic acid, cinnamic acid, salicylic acid, 2-phenoxybenzoic acid, p-toluenesulfonic acid, and sulfonic acids such as methanesulfonic acid and 2-hydroxyethanesulfonic acid. It may form monoacid or diacid and such salts may exist in hydrate, solvate or substantially anhydride form. In general, acid addition salts of these compounds are more soluble in water and various hydrophilic organic solvents and generally exhibit higher melting points when compared to their free base form.

"Pharmaceutically acceptable basic addition salt" means a nontoxic organic or inorganic basic addition salt of a compound of Formula (I) or an intermediate thereof. Examples include alkali metal or alkaline-earth metal hydroxides such as sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide or barium hydroxide; Ammonia and aliphatic, cycloaliphatic or aromatic organic amines such as methylamine, trimethylamine and picoline. Selection of suitable salts may be important since the esters are not hydrolyzed. Selection criteria for suitable salts will be known to those skilled in the art.

"Solvate" means a compound of Formula I or a pharmaceutically acceptable salt thereof, wherein molecules of a suitable solvent are incorporated into the crystal lattice. Suitable solvents are substantially nontoxic at the dosage administered as solvate to obtain the desired effect. Examples of suitable solvents are ethanol and the like.

The term “stereoisomers” is a general term for all isomers of individual molecules that differ only in atomic orientation in space. This includes enantiomers (enantiomers), geometric (cis / trans) isomers, and isomers (diastereomers) of compounds having at least one non-enantiomeric chiral center to each other.

The term "patient" means primates such as, for example, rats, mice, dogs, cats, warm-blooded animals such as guinea pigs and humans.

The term “treat” or “treating” means alleviating the symptoms, eliminating the cause of a temporary or permanent baseline symptom, or preventing or delaying the onset of symptoms of a named disease or condition.

The term "therapeutically effective amount" means an amount of a compound effective to treat a named disease or condition.

The term “pharmaceutically acceptable carrier” is a non-toxic solvent, dispersion, excipient, adjuvant or other substance which is mixed with an active ingredient to form a pharmaceutical composition, ie a dosage form which is administrable to a patient. One example of such a carrier is a pharmaceutically acceptable oil typically used for parenteral administration.

The term "schizophrenia" refers to schizophrenia, schizophrenia, schizophrenia, and psychiatric disorders (wherein the term "psychiatric" refers to delusions, prominent hallucinations, disorganized language, or deconstructed or strained behavior). [Reference: Diagnostic and Statistical Manual of Mental Disorder, 4th edition, American Psychiatric Association, Washington DC].

The present invention relates to compounds that bind to the dopamine D4 receptor in an alternative manner, instead of the dopamine D2 receptor.

In an embodiment of the invention, compounds of formulas (I) and (II) include compounds wherein R ₁ is H and R ₂ is C _4-9 alkyl.

In certain embodiments of the invention, the compounds of formulas (I) and (II) have the same R ₁ in H and the same R ₂ in n-pentyl.

In other embodiments of the invention, compounds of Formulas I and II are those wherein R ₁ is H and R ₂ is naphthyl; Phenyl; Phenyl and a 5 or 6 membered heterocycle substituted with one or two groups selected from methyl, methoxy, nitro, bromo, chloro, fluoro, trifluoromethoxy, trifluoromethyl, phenyl and cyano Compound selected from fused phenyl.

In certain embodiments of the invention, compounds of Formulas I and II are those wherein R ₁ is H and R ₂ is

4-methylphenyl;

4-trifluoromethoxyphenyl;

4-trifluoromethylphenyl;

4-nitrophenyl;

3-cyanophenyl;

3-trifluoromethylphenyl;

4-bromophenyl;

3,5-difluorophenyl;

2-cyanophenyl;

2-chlorophenyl;

2-nitrophenyl;

3-methylphenyl;

2-phenylphenyl;

3-bromophenyl;

3,5-bis (trifluoromethyl) phenyl;

3-nitrophenyl;

4-cyanophenyl;

3-methoxyphenyl;

2-naphthyl;

1,2-methylenedioxyphenyl; (preferably, R ₂ together with the methylene to which it is attached form piperonyl)

4-chlorophenyl; And

Compounds that are 3-chlorophenyl.

In other embodiments of the invention, compounds of Formulas (I) and (II) are compounds wherein R ₁ is H, R ₂ is a coumarin moiety shown below, and R ₃ and R ₄ are selected from H and C _1-4 alkoxy.

Certain embodiments of the invention include compounds of Formulas I and II wherein R ₁ is H and R ₂ is 1- (6,7-dimethoxycoumarin) and 1- (7-methoxycoumarin).

In other embodiments of the invention, the compounds of Formulas I and II are those wherein R ₁ is halo; Aryl; And aryl substituted with one or two groups independently selected from H, halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy and cyano and R ₂ C _4-9 alkyl, naphthyl, phenyl; To a phenyl, 5- or 6-membered heterocycle substituted with one or two groups selected from methyl, methoxy, nitro, bromo, chloro, fluoro, trifluoromethoxy, trifluoromethyl, cyano and phenyl Fused phenyl and the following coumarin moieties, wherein R ₃ and R ₄ are selected from H and C _1-4 alkoxy.

In a more preferred embodiment of the invention, the compounds of formulas (I) and (II) are selected from aryl wherein R ₁ is attached to the seventh carbon of the halo and 7 membered ring and R ₂ is methyl, methoxy, nitro, bromo, chloro, fluoro Or phenyl substituted with one or two groups selected from trifluoromethoxy, trifluoromethyl, cyano and phenyl; R ₂ is naphthyl or a phenyl fused to a 5 or 6 membered heterocycle.

In certain embodiments of the invention, the compounds of formulas (I) and (II) are selected from thienyl wherein R ₁ is attached to the seventh carbon of the bromo and 7 membered ring and R ₂ is substituted with 1,2-methylenedioxyphenyl and chloro Compound selected from phenyl.

In certain embodiments of the invention, the compounds of Formulas I and II are:

2- (4-benzyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- (4-hexyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one;

2- [4- (3,5-difluorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (2-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (2-phenylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- {4- [3,5-bis (trifluoromethyl) benzyl] -1-piperazinyl} -2,4,6-cycloheptatrien-1-one;

2- [4- (3-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

7-bromo-2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- (4-piperonyl-1-pyrerazinyl) -7-thien-2-yl-2,4,6-cycloheptatrien-1-one;

2- {4- [1- (6,7-dimethoxycoumarin) methyl] -1-piperazinyl} -2,4,6-cycloheptatrien-1-one; And

2- {4- [1- (7-methoxycoumarin) methyl] -1-piperazinyl} -2,4,6-cycloheptatrien-1-one.

For its enhanced D4 efficacy, compounds of formula (I) and (II) are preferred:

2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- (4-hexyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one;

2- [4- (3-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; And

2- (4-piperonyl-1-piperazinyl) -7-thien-2-yl-2,4,6-cycloheptatrien-1-one.

Particularly preferred compounds of formulas I and II are:

2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; And

2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one.

Most preferred compounds of formula (I) and (II) are:

2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one;

2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one:

2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one;

7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; And

2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one.

Acid addition salts of the compounds of formulas (I) and (II) are most suitably formed from pharmaceutically acceptable acids, for example inorganic acids such as hydrochloric acid, sulfuric acid or phosphoric acid and organic acids such as succinic acid, maleic acid, acetic acid or fumaric acid. It includes that formed by). Other non-pharmaceutically acceptable salts, such as oxalates, can be used, for example, for the separation of compounds of formula (I) for laboratory or subsequent conversion to pharmaceutically acceptable acid addition salts. Also solvates or hydrates of the invention are included within the scope of the invention.

The conversion of the proposed compound salt to the desired compound salt is carried out by applying standard techniques, wherein the aqueous salt of the presented salt is treated with a solution of base, for example sodium carbonate or potassium hydroxide, followed by free salt extraction with a suitable solvent such as ether. Liberate. The free base is then separated from the aqueous fraction, dried and treated with the required acid to give the desired salt.

Compounds of the invention can be prepared by methods analogous to those known in the art. The present invention thus provides in a further aspect a process for preparing a compound of formulas I and II or salts, solvates or hydrates thereof, wherein R ₁ is H or halo, comprising one of two possible methods.

The first involves coupling a reagent of Formula A with a reagent of Formula B in reflux methanol as described in EP 034,894 and useful in synthetic or commercial methods for the corresponding reagent of Formula B. Can be used when

R ₁ is a suitable Trojan polron H or halo reagent (A) can be synthesized using the established techniques that are treated with methylated [Reference: Pietra, F. Chem when one R ¹ is H. Rev. 1973, 73: 293 and Takeshita, H. when R ¹ is halo; Mori, A. Synthesis, 1986, 578]. For example, tropolone is treated with dimethyl sulfate and potassium carbonate in acetone.

It is known that the compound of Reagent B is either commercially available or can be prepared by conventional methods. For example, methods useful for preparing the compounds of Reagent B are described in EP 034,894.

Compounds of formulas (I) and (II) can also be prepared by coupling a reagent of formula (C) with a reagent of formula (D) in the presence of a base such as potassium carbonate in an inert organic solvent such as acetonitrile as described herein. Reagent C compounds wherein R ₁ is H or halo are described, for example, using Bagli [J. Med. Chem. 1984, 27: 875] and reacts reagent A with piperazine according to the method described. Reagent D can be obtained commercially or synthesized by established techniques, for example by treating the corresponding alcohols with halogenating agents such as CBr ₄ and triphenylphosphine (X = Br) or thionyl chloride (X = Cl). can do.

R ₁ is aryl; Or aryl substituted with one or two groups independently selected from H, halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy and cyano Is reacted with a metallo-aryl compound R ₁ -M attached to a carbon node of an aryl group, wherein R ₁ is as defined above and M is an optionally substituted metal substituent, suitable for cross-linking reactions. Can be prepared from compounds of Formulas I and II wherein R ₁ is halo using standard palladium catalyzed crosslinking techniques. Examples of such M groups include (alkyl) ₃ Sn-, (alkyl) ₂ B-, (HO) ₂ B-, (alkoxy) ₂ B-, Li, Cu, chloroZn or haloMg. Most preferred M group is chloroZn. The reaction is carried out in an inert solvent, optionally in the presence of a base, lithium chloride and a suitable catalyst. Suitable catalysts include palladium (II) and palladium (0) species such as palladium (II) acetate, palladium (II) chloride and tetrakis (triphenylphosphine) palladium (0). Preferred catalyst is tetrakis (triphenylphosphine) palladium (0). Suitable inert solvents include acetonitrile, N, N-dimethylformamide and tetrahydrofuran, with tetrahydrofuran being preferred. The reaction is carried out at a temperature of 25 to 100 ° C, preferably 50 to 100 ° C. Compounds of formula R ₁ -M can be prepared separately or in situ by standard metallization from reagents of R ₁ -Y, wherein Y is halo or triflate. For example, compound R ₁ -M wherein M is chloro-Zn can be prepared in situ form prior to crosslinking reaction by treating R ₁ -Br with n-butyl lithium and zinc chloride in tetrahydrofuran at -78 ° C. have.

Clozapine-based binding profiles of the compounds indicate their use as a medicament that may be useful as a neurosuppressive agent in the treatment of various diseases involving D4 receptor stimulation, such as for the treatment of anxiety and schizophrenia. Thus, in other aspects, the present invention provides pharmaceutical compositions useful for treating D4-related medical conditions, wherein the compound of Formula II is present in an amount effective to antagonize D4 receptor stimulation with a pharmaceutically acceptable carrier. The compound of formula (II) further comprises a compound included by formula (I), but wherein R ₂ is phenyl or 3,4-dimethoxyphenyl. In another aspect, the present invention provides a method of treating a medical condition in which a D4 antagonist is indicated, comprising administering to a patient a compound of Formula II and a pharmaceutically acceptable carrier thereof effective for antagonizing D4 receptor stimulation. .

The compounds of the present invention can be administered in standard pharmaceutical compositions for use in medicine. Thus in a further aspect the present invention provides a pharmaceutical composition comprising a pharmaceutically acceptable carrier and a compound of Formula II or a pharmaceutically acceptable salt, solvate or hydrate thereof in an amount effective to antagonize D4 receptor stimulation.

The compounds of the present invention can be administered by conventional routes such as oral, parenteral, buccal, sublingual, nasal, rectal or transdermal administration and pharmaceutical compositions can be prepared thereby. Compounds of formulas (I) and (II) and their stereoisomers, solvates, hydrates, or pharmaceutically acceptable salts thereof when administered orally are prepared in liquids, such as syrups, suspensions or emulsions, or tablets, capsules and sugar tablets. It can be prepared in the same solid form. Liquid formulations are generally in combination with suspending agents, preservatives, fragrances or coloring agents of suitable pharmaceutical liquid carriers such as ethanol, glycerin, non-aqueous solvents such as polyethylene glycol, oils, or compounds in water or pharmaceutically acceptable salts. It may consist of a suspension or a solution. Tablet-like compositions can be prepared using suitable pharmaceutical carriers which are used continuously for the preparation of solid preparations. Examples of such carriers include magnesium stearate, starch, lactose, sucrose and cellulose. Capsule compositions can be prepared using continuous encapsulation methods. For example, pellets containing the active ingredient may be prepared using standard carriers and then filled into hard gelatin capsules, and the dispersions or suspensions may generally be dispersed in a suitable pharmaceutical carrier such as an aqueous gum, cellulose, silicate or oil. And dispersions or suspensions filled with soft gelatin capsules.

Typical parenteral compositions are solutions or suspensions of a compound or pharmaceutically acceptable salt in a heterogeneous aqueous carrier or parenterally acceptable oil, such as polyethylene glycol, polyvinyl pyrrolidone, lecithin, arachis oil or sesame oil. Is done. Alternatively, the solution may be lyophilized and then reconstituted with a suitable solvent just prior to administration.

Compositions for nasal administration may be conveniently prepared as aerosols, drops, gels and powders. Aerosol formulations typically comprise a solution or microsuspension of the active substance in a physiologically acceptable aqueous or non-aqueous solvent and are generally present in a single or multidose in a heterogeneous form in a sealed container, for use with a spray device. It may take the form of a cartridge or a refill. Alternatively, the sealed container may be a unit dispensing device such as a single dose nasal inhaler or an aerosol dispenser equipped with a metering valve to be removed after use. If the dosage form comprises an aerosol dispenser, it may contain a propellant, which may be a compressed gas such as compressed air, or an organic propellant, such as fluorochlorohydrocarbon. Aerosol dosage forms can also take the form of a pump-spray.

Compositions suitable for buccal or sublingual administration include tablets, sugar tablets and troches, wherein the active ingredient is formulated with a carrier such as sugar, acacia, tragacanth or gelatin and glycerin. Compositions for rectal administration are, for convenience, suppositories containing conventional auxiliary bases, such as cocoa butter.

Preferably, the composition is in unit dosage form such as a tablet, capsule or ampoule. Suitable unit dosages, ie, therapeutically effective amounts, can be measured during clinically appropriately designated clinical trials for each of the conditions in which administration of the selected compound is indicated and can, of course, vary depending on the desired clinical endpoint. It is contemplated that dosage sizes suitable for administering the compounds of the Examples may be approximately equivalent or somewhat smaller than the compounds currently used for clozapine. Thus, each dosage unit for oral administration may contain from 1 to about 500 mg and may be administered in any number of times suitable for initial and sustained treatment.

For laboratory use as a ligand, the present invention can be stored in a package for reconstitution and use. The present compounds can be used to distinguish dopamine receptors from other receptor types in the receptor population, such as glutamate and opioid receptors, and in particular between D4 and D2 receptors. The latter can be obtained by incubating the preparations of the D4 and D2 receptors with the D4 selective compounds of the invention, followed by incubation of the obtained preparations with radiolabeled dopamine receptor ligands such as ³ H-Spiferon. The D2 and D4 receptors are then distinguished by measuring differences in membrane-bound radioactivity with D4 receptors that exhibit lower radioactivity, ie, lower ³ H-Spiferon binding.

In other embodiments of the invention, the compounds are provided in labeled form by incorporation into a radiolabeled form, such as ³ H or ¹⁴ C, or by conjugation to ¹²⁵ I or ¹²³ I. This radiolabeled form can be used directly to distinguish dopamine D4 and dopamine D2 receptors. In addition, radiolabeled forms of the compounds may be developed to block for more potential dopamine D4 ligands by measuring the ability of the test ligand to replace the radiolabeled compounds of the invention.

Example 1 (a)

2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one

2-methoxytropon (1.36 g, 10.0 mmol) in methanol (50.0 mL) [manufactured by Pietra, F. Chem Review, 1973, 73: 293] and 1-piperonylpiperazine (6.61 g, 30.0 m) Mol)) is refluxed for 16 h. After cooling to room temperature the solvent is removed in vacuo. The residue is column chromatographed using ethyl acetate as eluent. The title compound is obtained as a yellow oil (1.24 g, 38%). MS (FAB) 325 (M ⁺ +1).

In a similar manner, the following additional compounds are prepared:

(b) 7-bromo-2-methoxytropon [manufacturer: Takeshita, H .; 7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one from Mori, A. Synthesis, 1986, 578.

Example 2 (a)

2- (1-piperazinyl) -2,4,6-cycloheptatrien-1-one acetic acid salt

Such compounds are described in Bagli, J. et al., J. Med. Chem. 1984, 27: 875, prepared from 2-methoxytropon and piperazine.

In a similar manner, the following additional compounds are prepared:

(b) 7-bromo-2- (1-piperazinyl) -2,4,6-cycloheptatrien-1-one acetic acid salt

Example 3 (a)

2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one

2- (1-piperazinyl) -2,4,6-cycloheptatrien-1-one acetic acid salt (0.171 g, 0.680 mmol, Example 2a), 3-methoxy in acetonitrile (2.00 mL) A mixture of benzyl chloride (0.118 g, 0.750 mmol) and potassium carbonate (0.276 g, 2.00 mmol) is stirred at room temperature for 16 hours. The solvent is removed in vacuo. The residue is triturated with dichloromethane and filtered. The filtrate is concentrated to dryness in vacuo and the residue is preparative thin layer chromatography using ethyl acetate: methanol (9: 1) as eluent. The title compound is obtained as a yellow oil (0.095 g, 45%); MS (FAB) 311 (M ⁺⁺ 1).

In a similar manner, the following additional compounds are prepared:

b) 2- (4-hexyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one from 1-bromohexane; Yellow oil (51%); MS (ES) 275 (M ⁺ +1).

c) 2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 4-cyanobenzyl bromide; Yellow solid (44%); Melting point 136-138 ° C .; MS (FAB) 306 (M ⁺ +1).

d) 2- [4-benzyl-1-piperazinyl] -2,4,6-cycloheptatrien-1-one from benzyl bromide.

e) 2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from α-bromo-p-xylene; MS (FAB) 295 (M ⁺ +1).

f) 2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 4- (trifluoromethoxy) benzyl bromide ; MS (FAB) 365 (M ⁺ +1).

g) 2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cyclohepta from α'-bromo-α, α, α-trifluoroxylene Trien-1-one; Melting point 111-113 ° C .; HRMS (FAB): MH ⁺ for C ₁₉ H ₁₉ F ₃ N ₃ O, calcd. 349.1529. Found 349.1528.

h) 2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 4-nitrobenzyl bromide; Melting point 108-110 ° C .; HRMS (FAB): MH ⁺ for C ₁₈ H ₁₉ N ₃ O ₃ , calcd. 326.1506, found 326.1512.

i) 2- [4- (3-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from α-bromo-m-tolunitrile.

j) 2- [4- (3-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6 from α'-bromo-α, α, α-trifluoro-m-xylene -Cycloheptatrien-1-one; MS (FAB) 349 (M ⁺⁺ 1).

k) 2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 4-bromobenzyl bromide; Melting point 122-124 ° C .; MS (FAB) 359 (M ⁺ +1).

l) 2- (2-methyl-4-naphthyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one from 2- (bromomethyl) -naphthalene; MS (FAB) 331 (M ⁺ +1).

m) 2- [4- (3,5-difluorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatriene from α-bromo-3,5-difluorotoluene -1-one.

n) 2- [4- (2-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from α-bromo-o-tolunitrile.

o) 2- [4- (2-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 2-chlorobenzyl bromide.

p) 2- [4- (2-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 2-nitrobenzyl bromide.

q) 2- [4- (3-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from α-bromo-m-xylene.

r) 2- {4- [1- (6,7-dimethoxycoumarin) methyl] -1-piperazinyl} -2,4, from 4- (bromomethyl) -6,7-dimethoxycoumarin 6-cycloheptatrien-1-one.

s) 2- {4- [1- (7-methoxycoumarin) methyl] -1-piperazinyl} -2,4,6-cyclohepta from 4- (bromomethyl) -7-methoxycoumarin Trien-1-one.

t) 2- [4- (2-phenylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 2- (bromomethyl) biphenyl.

u) 2- [4- (3-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 3-bromobenzyl bromide.

v) 2- {4- [3,5-bis (trifluoromethyl) benzyl] -1-piperazinyl-2,4,6-cyclo from 3,5-bis (trifluoromethyl) benzyl bromide Heptatrien-1-one.

w) 2- [4- (3-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 3-nitrobenzyl bromide.

x) 2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 4-chlorobenzyl bromide; HRMS (FAB): MH ⁺ for C ₁₈ H ₁₉ CIN ₂ O, calcd. 315.1264. Found 315.1270.

y) 2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one from 3-chlorobenzyl bromide; HRMS (FAB): MH ⁺ for C ₁₈ H ₁₉ CIN ₂ O, calcd. 315.1264. Found 315.1258.

z) 7-bromo-2- from 7-bromo-2- (1-piperazinyl) -2,4,6-cycloheptatrien-1-one and 4-chlorobenzyl bromide of Example 2b [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one.

Example 4

(a) 2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one, maleic acid salt

2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one (0.949 g, 2.92 mmol, Example 1a) was converted to diethyl ether (15.0 mL). Is dissolved in and a maleic acid solution (0.373 g, 3.22 mmol) in methanol (0.50 mL) is added. The resulting mixture is stirred at rt for 16 h. The mixture was filtered to afford maleic acid salt as a yellow solid (1.09 g, 85%); Melting point 142-144 ° C .; MS (ES) 325 (M ⁺ -C ₄ H ₄ O ₄ ).

In a similar manner, maleic acid salts of the following additional compounds are prepared:

b) 2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one (Example 3f); Melting point 170-172 ° C .; HRMS (FAB): MH ⁺ for C ₁₉ H ₁₉ F ₃ N ₂ O ₂ (free base), calculated 365.1523. Found 365.1477.

c) 2- (2-methyl-4-naphthyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one (Example 3l); Melting point 170-172 ° C.

Example 5

2- (4-piperonyl-1-piperazinyl) -7-thien-2-yl-2,4,6-cycloheptatrien-1-one

To a solution of 2-bromothiophene (1.0 g, 6.1 mmol) in tetrahydrofuran (50 mL) at 78 ° C. was added n-butyl lithium (1.6 M in cyclohexane, 4.0 mL) and the resulting solution was stirred for 5 minutes. do. At this time, ZnCl ₂ (0.5M in THF, 20 mL) is added and the solution is allowed to warm to room temperature over 2 hours. The reaction mixture was then added to palladium tetrakis (triphenylphosphine) (200 mg) and 7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4 in tetrahydrofuran (5 mL). An acetic acid salt solution of, 6-cycloheptatrien-1-one (300 mg, 0.74 mmol, Example 1b) is added and the resulting mixture is refluxed for 18 hours. The reaction is quenched with saturated aqueous ammonium chloride solution and the product is extracted with methylene chloride (3 x 200 mL). The crude product is purified by silica gel chromatography to give the title compound as dark yellow oil (50 mg, 50%).

Example 6

Receptor binding assay

The D2 and D4 receptor-binding affinity of the compounds of Examples 1 and 2 is measured according to their ability to reduce the binding of ³ H-sphyrone as compared to the relevant compound clozapine. The efficacy of a test compound to reduce ³ H-Spiferon binding is correlated with its binding affinity for the receptor.

D4 receptor manufacturing

HEK 298 (human fetal kidney) cells stably transfected with the human D4 receptor [D4.2 sub-type] were grown in a NUNC cell factory for 5 days (75% fusion) without changing the medium and versen (cells) About 19 mg of cells per factory tray). Cells are then centrifuged for 10 minutes at 5000 rpm (GS3 rotor) in a Sorval centrifuge and pellets are quickly frozen in liquid nitrogen and stored at -80 ° C until used for binding assays. If used for the assay, cells are thawed on ice for 20 minutes before 10 ml of culture buffer (50 mM Tris, 1 mM EDTA, 4 mM MgCl ₂ , 5 mM KCl, 1.5 mM CaCl ₂ , 120 mM NaCl, pH 7.4) is added. The cells are then vortexed, resuspended in pellets, adjusted to 7 and homogenized for 15 seconds with a Kinematica CH-6010 Kriens-LU homogenizer. The concentration of receptor protein is measured using the Pierce BCA assay.

D2 receptor manufacturing

GH ₄ C ₁ (rat pituitary) cells stably transfected with human D2 receptor (short isoform) are grown for 5 days in HAM'S F10 medium in a NUNC cell factory. 100 μM ZnSO _{4 is added} to the cells (D2 promoter is zinc inducible). After 16 hours fresh medium is added to allow cells to regenerate for 24 hours. Cells are collected using Versine and then centrifuged at 5000 rpm (GS3 motor) in a Sorbal centrifuge for 10 minutes. The pellet is quickly frozen in liquid nitrogen and stored at -80 ° C until used for binding assays. When used in the assay, cells are thawed on ice for 20 minutes. The cell factory produces about 72 mg of protein each. 10 ml of culture buffer is then added to pellets which are vortexed, resuspended and adjusted to 7 and homogenized with a Kinematica CH-6010 Kriens-LU homogenizer. Receptor protein concentrations are measured using the Pierre Body BCA assay.

Total Spifferon Binding Assay

100 μl of membrane equivalent solution (50 μg protein) was added to 300 μl of culture buffer in 96-well polypropylene plate (1 ml per well) and 100 μl of ³ H-Spiferon (final concentration 0.25 nM) [90 diluted in borosilicate glass vial. Incubation is initiated by addition to a solution of Ci / mmol Amersham. The plate is vortexed and incubated for 90 minutes at room temperature. The binding reaction is stopped by filtration using a Packard Harvester. Samples are filtered under vacuum on a glass fiber filter plate (Whatman GF / B) pre-soaked in 0.3% polyethyleneimine (PEI) in 50 mM Tris buffer (pH 7.4) for 2 hours. The filter is then washed six times with 7 ml of ice cold 50 mM Tris buffer (pH 7.4). Dry the filter plate overnight and add 35 μl of Microscint-O (Packard). Plates are sealed and measured at Packard Top Count (3 minutes per well).

Nonspecific binding assay for D4

100 μl of membrane equivalent solution (50 μg protein) was added to 200 μl of culture buffer in 96-well polypropylene plate (1 ml per well) and 100 μl of ³ H-sphyrrone (90 Ci diluted to 0.25 nM in borosilicate glass vials). / mmol Amersham) and 100 μl fresh dopamine (30 μM final concentration) (manufactured by Research Biochemicals Inc., photoprotected and dissolved in culture buffer) initiate incubation. The plate is vortexed and incubated for 90 minutes at room temperature where the binding reaction is stopped by filtration. The filter is washed and calibrated using the same method as in the overall binding assay described above to obtain a nonspecific binding value (NSB).

Nonspecific binding assay for D2

The assay uses the same method as the nonspecific binding assay for D4 except using 2 μM (final concentration) of sulfide (manufactured by Research Chemicals Inc.) in place of dopamine.

Alternative binding analysis

In a 96-well polypropylene plate (1 ml per well), 100 μl membrane equivalent (50 μg protein) was added to 200 μl of culture buffer, 100 μl of ³ H-Spiferon (final concentration 0.25) (90 Ci diluted in borosilicate glass vial. / mmol, Amersham) and 100 μl of test compound prepared from 1 mM stock solution stored at −20 ° C. in polypropylene cryogenic storage vials until dissolved in DMSO and diluted in culture buffer in 96-well polypropylene plates. Add to solution to initiate incubation. The plate is vortexed and incubated for 90 minutes at room temperature where the binding reaction is stopped by filtration. The filter is washed and calibrated using the same method as in the overall binding assay described above to obtain an alternative binding value (B _D ).

Calculation

The test compounds are analyzed at initial concentrations at 1 μM and 0.1 μM, followed by a range of selected concentrations such that the average dose can inhibit about 50% of the ³ H-Spiferon binding. In the absence of test compound (B ₀ ) specific binding is the difference between total binding (B _T ) -nonspecific binding (NSB) and similarly specific binding (in the presence of test compound (B)) is alternative binding (B _D )- Difference in nonspecific binding (NSB). IC ₅₀ is determined from the logarithmic-log plot of inhibition response curve,% B / B ₀ versus test compound concentration.

Ki is determined from the Cheng and Prustoff transformations:

K _i = IC ₅₀ / (1+ [L] / K _D )

In the above conversion formula,

[L] is the concentration of ³ H-Spiferon used in the assay,

K _D is the dissociation constant of ³ H-Spiferon independently determined under the same binding conditions.

The analytical results are shown in the table below and clearly show the advantages with regard to the D4 selectivity and / or binding affinity of the compounds of the invention for clozapine.

D ₄ affinity and selectivity

Example 7

Action analysis

D4 receptor responses to dopamine and other agonists by reducing adenyl cyclase mediate the production of cyclic AMPs. Certain test compounds are analyzed for their ability to reverse dopamine inhibition of adenyl cyclase by the following method. Forskolin is used to enhance the base adenyl cyclase activity.

Five CHO Pro cells stably expressing human D4.2 receptors were treated with DMEM [(Dulbecco Modified Eagle Medium) / F12 (10% FCS (mortal bovine serum) and G418 (Zinetissen disulfate)). Six well plates in nutrient mixture F12 (Ham))] are left to stand and incubated at 37 ° C. in a CO ₂ incubator. Allow cells to grow to about 70% fusion before being used for analysis.

Antagonist Analysis

The culture medium of each well is removed and the wells are washed once with serum free medium (SFM) (DMEM / F12) medium. Then 2 ml of fresh SFM + IBMX medium (SFM with 0.5 mM IBMX, 3-isobutyl-1-methylxanthine, 0.1% ascorbic acid and 10 μM pargiline) was added to each well and then in a CO ₂ incubator for 10 minutes. Incubate at 37 ° C. SFM + IBMX medium was removed after incubation and fresh SFM + IBMX medium was a) forskolin (final concentration 10 μM); b) dopamine and forskolin (both at a final concentration of 10 μΜ); And c) to the wells separately with one of the test compounds (10 ^-4 to 10 ^-6 M). Base adenyl cyclase activity is measured from the wells with only added SFM + IBMX medium.

The cells are then incubated at 37 ° C. for 30 minutes in a CO ₂ incubator. After incubation, the medium is removed from each well and then washed once with 1 ml of PBS (phosphate buffered saline). The wells are then treated with 1 ml of cold 95% ethanol: 5 mM EDTA (2: 1) at 4 ° C. for 1 hour each. Cells from each well are then scraped off and transferred to separate Eppendorf tubes. The tube is centrifuged at 4 ° C. for 5 minutes and the supernatant is transferred to a new Ippendorf tube. Pellets are decanted and the supernatant is stored at 4 ° C. until analyzed for cAMP concentration. The cAMP content, measured in mol / well for each extract, is determined by EIA (enzyme-immunoassay) using the Amersham Biotrack cAMP EIA kit (Amersham RPN 225).

Total inhibition of forskolin-stimulated adenyl cyclase activity by dopamine (I ₀ ) was determined by cAMP in forskolin-treated cells (C _f ) and dopamine-forskolin treated cells (C _d ). Measured by the difference in concentration.

I _O = C _f -C _d

Net suppression of forskolin-stimulated adenyl cyclase activity by dopamine in the presence of an antagonist (I) was observed in forskolin-treated cells (C _f ) and test compounds, dopamine and forskolin treated cells ( It is measured by the difference in cAMP concentration in C).

I = C _f -C

The ability of the test compound to reverse dopamine inhibition (% reverse,% R) is determined using the formula:

% R = (1-I / I ₀ ) × 100

compound Inversion% of the dopamine effect 1 μM 10 μM Clozapine 6 58 2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one 32 65 2- (4-hexyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one 45 50

Agonist Analysis

Test compound and forskolin (final concentration 10 μM) are added to D4.2 stably expressing CHO cells prepared as described above. Cells are incubated as above, extracted and measured for cAMP concentration. The agonist activity of the test compound may cause a decrease in cAMP concentration compared to cells treated with forskolin (C _f ) alone. Since no decrease is observed, the test compound shows no dopamine agonist activity. Based on structural and biological action similarities, it is assumed that the remaining compounds of the present invention may also exhibit dopamine antagonist activity.

Claims (22)

A compound of formula I, a stereoisomer, solvate or pharmaceutically acceptable salt thereof. Formula I In the above formula, R ₁ is H; Halo; Aryl; Or aryl substituted with one or two groups independently selected from halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy or cyano, R ₂ is C _4-9 alkyl; Phenyl or phenyl substituted with one or two groups independently selected from OH, cyano, halo, C _1-4 alkoxy, C _1-4 alkyl, trifluoromethyl, trifluoromethoxy, nitro or phenyl; Naphthyl; Phenyl fused to a 5 or 6 membered heterocycle; Coumarin residues Wherein R ₃ and R ₄ are independently selected from H, C _1-4 alkyl and C _1-4 alkoxy) or 1,2-methylenedioxy phenyl, Provided that when R ₁ is H, R ₂ is not phenyl or 3,4-dimethoxyphenyl. A compound according to claim 1, wherein R ₂ is phenyl substituted with one or two groups selected from methyl, methoxy, nitro, bromo, chloro, fluoro, trifluoromethoxy, trifluoromethyl or cyano . The compound of claim 2, wherein R ₂ is 4-methylphenyl; 4-trifluoromethoxyphenyl; 4-trifluoromethylphenyl; 4-nitrophenyl; 3-cyanophenyl; 3-trifluoromethylphenyl; 4-bromophenyl; 3,5-difluorophenyl; 2-cyanophenyl; 2-chlorophenyl; 2-nitrophenyl; 3-methylphenyl; 2-phenylphenyl; 3-bromophenyl; 3,5-bis (trifluoromethyl) phenyl; 3-nitrophenyl; 4-cyanophenyl; 3-methoxyphenyl; 2-naphthyl; 3-chlorophenyl, 4-chlorophenyl or 1,2-methylenedioxy phenyl. The compound of claim 3, wherein R ₁ is H, halo or aryl. The compound of claim 4, wherein R ₁ is H, bromo or thiophene. 6. The compound of claim 5, wherein R ₁ is attached at the 7 position of the 7 membered ring. The compound of claim 6, wherein R ₁ is thiophene or R ₂ is 1,2-methylenedioxy phenyl. The compound of claim 1, wherein R ₂ is a coumarin residue and R ₄ and R ₅ are independently selected from H or C _1-4 alkoxy. The compound of claim 8, wherein R ₂ is 1- (6,7-dimethoxycoumarin) or 1- (7-methoxycoumarin). The compound of claim 9, wherein R ₁ is H. 11. 2. A compound according to claim 1 further comprising: 2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- (4-hexyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one; 2- [4- (3,5-difluorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (2-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (2-phenylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- {4- [3,5-bis (trifluoromethyl) benzyl] -1-piperazinyl} -2,4,6-cycloheptatrien-1-one; 2- [4- (3-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 7-bromo-2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- (4-piperonyl-1-piperazinyl) -7-thien-2-yl-2,4,6-cycloheptatrien-1-one; 2- {4- [1- (6,7-dimethoxycoumarin) methyl] -1-piperazinyl} -2,4,6-cycloheptatrien-1-one; or 2- {4- [1- (7-methoxycoumarin) methyl] -1-piperazinyl} -2,4,6-cycloheptatrien-1-one. 12. The composition of claim 11 further comprising: 2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- (4-hexyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one; 2- [4- (3-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; or 2- (4-piperonyl-1-piperazinyl) -7-thien-2-yl-2,4,6-cycloheptatrien-1-one. 13. The compound of claim 12 further comprising: 2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- [4- (3-methoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-cyanobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (3-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-methylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; or 2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one. The method of claim 13, further comprising: 2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; 2- [4- (4-bromobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethylbenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-trifluoromethoxybenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one: 2- [4- (4-nitrobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 2- [4- (4-chlorobenzyl) -1-piperazinyl] -2,4,6-cycloheptatrien-1-one; 7-bromo-2- (4-piperonyl-1-piperazinyl) -2,4,6-cycloheptatrien-1-one; or 2- (4-naphthyl-2-methyl) -1-piperazinyl-2,4,6-cycloheptatrien-1-one. The compound of claim 1, wherein R ₁ is H and R ₂ is phenyl substituted with a substituent of one of halo, cyano, alkoxy, trifluoromethoxy, trifluoromethyl or C _1-4 alkyl; Or 1,2-methylenedioxy phenyl. A pharmaceutical composition comprising a pharmaceutically acceptable carrier and a therapeutically effective amount of a compound of formula II. Formula II In the above formula, R ₁ is H; Halo; Aryl; And aryl substituted with one or two groups independently selected from halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy and cyano, R ₅ is C _4-9 alkyl; Phenyl or phenyl substituted with one or two groups independently selected from OH, cyano, halo, C _1-4 alkoxy, C _1-4 alkyl, trifluoromethyl, trifluoromethoxy, nitro or phenyl; Naphthyl; Phenyl fused to a 5 or 6 membered heterocycle; And coumarin residues Wherein R ₃ and R ₄ are independently selected from H, C _1-4 alkyl and C _1-4 alkoxy. The pharmaceutical composition of claim 16, wherein when R ₁ is H, R ₂ is phenyl or 3,4-dimethoxyphenyl. Use of a compound according to claim 1 in any combination with a pharmaceutical carrier for the manufacture of a pharmaceutical composition for antagonizing the dopamine effect at a D4 receptor in a patient. Use of a compound according to claim 1 used in any combination with a pharmaceutical carrier for preparing a pharmaceutical composition for treating schizophrenia. Use of a compound according to claim 1 used in any combination with a pharmaceutical carrier for preparing a pharmaceutical composition for treating anxiety. The compound of claim 1 for use as a pharmaceutically active compound. A method of preparing a compound of Formula I, a stereoisomer, solvate or pharmaceutically acceptable salt thereof, comprising coupling a reagent of Formula A with a reagent of Formula B in reflux methanol. Formula I Formula A Formula B In the above formula, R ₁ is H; Halo; Aryl; Or aryl substituted with one or two groups independently selected from halo, C _1-4 alkyl, C _1-4 alkoxy, nitro, trifluoromethyl, trifluoromethoxy or cyano, R ₂ is C _4-9 alkyl; Phenyl or phenyl substituted with one or two groups independently selected from OH, cyano, halo, C _1-4 alkoxy, C _1-4 alkyl, trifluoromethyl, trifluoromethoxy, nitro or phenyl; Naphthyl; Phenyl fused to a 5 or 6 membered heterocycle; Coumarin residues Wherein R ₃ and R ₄ are independently selected from H, C _1-4 alkyl and C _1-4 alkoxy) or 1,2-methylenedioxy phenyl, Provided that when R ₁ is H, R ₂ is not phenyl or 3,4-dimethoxyphenyl.