NOVEL PYRIDYL- AND PYRIMIDYLPIPERAZINE DERIVATIVES

Abstract: The present invention concerns novel compounds of general formula (I) wherein Ar are the same or different and selected from (a), (b) wherein R3 is fluoro or hydrogen, R1 and R2 are the same or different and selected from hydrogen or lower alkyl; n is 2 or 3, X is nitrogen or methine. When X is nitrogen Y is methylene. When X is methine Y is selected from nitrogen or oxygen. A is selected from pyrimidyl or pyridyl derivatives: (c), (d), (e), (f). The new compounds are useful for treating mental disorders.

Description: NOVEL PYRIDYL- AND PYRIMIDYLPIPERAZINE DERIVAT IV Background There is an urgent need for efficient drugs in the treatment of mental disorders which are more effective and which have fewer side effects than the drugs in clinical use today. Antipsychotic drugs in current use produce a range of troublesome extrapyramidal movement disorders (e.g. acute dystonic reactions and tardive dyskinesia) and are poor i ameliorating the negative symptoms (e.g. restricted or blunted emotional arousal) of schizophrenia. The main disadvantage of the anti-depressants is that they fail to alleviate depression in 30 to 40 % of patients. Anxioltyics are commonly associated with addictive properties. Prior An Various pyridyl- and pyrimidyl-piperazine derivates pharmacologically active in the centr nervous system are known in the art. Some representative examples can be mentioned. Azaperone, a neuroleptic drug of the butyrophenone series, is a sedative for pigs. Buspir is an anxiolytic. The anxiolytic effect is thought to be mediated via effects on the 5HT- receptors. Azaperone Buspirone SUBSTITUTE SHEET In the US Pat No. 4937245, compounds of the general formula C is disclosed wherein A is selected from pyridyl or pyrimidyl group, e.g. wherein preferably R6 is hydrogen and R7 is cyano, amides, methoxy or hydrogen substituent in the 3-position of the pyridyl ring, useful for the treatment of mental disord such as psychoses, depression and anxiety. Description of the invention According to the invention there are provided novel compounds having the general formula (I) SUBSTITUTE SHEET wherein Ar are the same or different and selected from wherein R3 is fluoro or hydrogen R j and R2 are the same or different and selected from hydrogen or alkyl; n is 2 or 3, X is nitrogen or methine . When X is nitrogen Y is methylene When X is methine or carbon Y is selected from nitrogen or oxygen, preferably oxygen. A is selected from the following pyrimidyl or pyridyl derivates. R4 and R5 are the same or different and selected from hydrogen, halogen, lower alkyl, electron donor groups such as lower alkoxy or hydroxy, electron acceptor groups such as cyano. nitro, trifluoromethyl, COOR-g, CONRγRg or CO-B; wherein Rg is hydrogen or SUBSTITUTE SHEET - A - lower alkyl; R7 and Rg are the same or different selected from hydrogen, lower alkyl or cycloalkyl; B is selected from wherein m is 1, 2, 3, or 4. R9 is selected from hydrogen or lower alkyl. And the pharmacologically active salts thereo Used in the foregoing definitions the term lower alkyl is meant to include straight and branched, saturated and unsaturated hydrocarbon groups having from 1 to 5 carbon atom the term cycloalkyl is meant to include cyclic, saturated and unsaturated hydrocarbon groups have from 3 to 8 carbon atoms, the term lower alkoxy is meant to include straight branched, saturated or unsaturated alkoxy groups having from 1 to 5 carbon atoms; the term halogen is meant to include fluoro, and bromo. The compounds of formula (I) have basic properties and, consequently, they may be converted to their therapeutically active acid addition salts by treatment with appropriated acids; e.g. inorganic acids such as hydrochloric, hydrobromic, sulfuric, nitric and phospho acid, or organic acids such as acetic, propanoic, glycolic, lactic, malonic, oxalic, succinic, fumaric, tartaric, citric and pamoic acid. Conversely, the salt form can be converted into the free base form by treatment with alkali. The compounds of formula (I) and their pharmaceutically acceptable salts have valuable pharmacological properties, making them useful for the treatment of mental disorders such as psychoses, depression and anxiety, senile dementia, Alzheimer's disease, anorexia and substance abuse disorders. Stress and anxiety in animals can also be treated. Clinical studies have lent support to 5-hydroxytryptamine (5-HT) as being important in the pathogenesis of mental disorders ,such as psychoses, depression, anxiety and substance abuse disorders. Considerable current activities are directed in the discovery of new SUBSTITUTE SHEET - b - psycho tropic drugs such as 5-HT-; ^ agonists, e.g., buspirone and ipsapirone, 5-HT2 antagonists e.g. amperozide and ritanserin, 5-HT uptake inhibitors e.g. fluoxetine and paroxetine. Since 5-HT^ and 5-HT2 receptors have been found to interact functionally, compounds with a combined 5-HTIA agonistic and 5-HT2 antagonistic activity would represent very interesting drugs for the treatment of patients suffering from mental disorders. The compounds of the present invention show a high affinity for 5-HTι ^ and 5-HT2 receptors. While compounds of the general formula (C) and formula (I) posses high affinity for serotonin 5-HT JA and 5-HT2 receptor subtypes., it has now quite surprisingly been foun that compounds of the present invention is superior from a safety point of view, rendering them useful in therapy in the central nervous system, especially in the serotonergic system the brain. Effective quantities of any of the foregoing pharmacologically active compounds of form (I) may be administrated to a human being or an animal for therapeutic purposes accordin to usual routes of administration and in usual forms such as solutions, emulsions, tablets, capsules and patches, in pharmaceutically acceptable carriers and parenterally in t form of sterile solutions. Formulations for parenteral administration may be in the form o aqueous or non-aqueous isotonic sterile injection solutions or suspensions. Although very small quantities of active materials of the present invention are effective when minor therapy is involved or in cases of administration to subjects having a relativel low body weight, unit dosages are usually from 0.5 mg upwards , depending on the condition to be treated and the age and weight of the patient as well as the response to th medication. The unit dose may be from 0.1 to 100 milligrams, preferably from 1 to 10 milligrams. Dail doses should preferably range from 1 to 50 milligrams. The exact individual dosages as w as daily dosages will, of course be determined according to standard medical principals under the direction of a physician or veterinarian . SUBSTITUTE SHEET Methods of preparation The compounds having the general formula (I) may be prepared by conventional methods. Method 1 R 1 Ar \ > -Y-(CH 2 ) 2 — L H--N ΠΛ N — A / Ar RT ^Chφn II III A compound of formula (II), wherein Ar, X and Y are as previously defined and L is a suitable leaving group such as halogen and alkyl- or arylsulfonate is reacted with a compound of formula (III) wherein K\, R2, A and n are as defined previously. The reactions may be carried out using standard N-alkylating procedures. Method 2 IV SUBSTITUTE SHEET VIII VIII A compound of formula IN, wherein Ar, Rj, R2, X, Y, and n are as previously defined i reacted with a compound of formula V, VI, VII, or VHI, wherein R4 and R5, are as previously defined and L is a suitable leaving group. Method 3 IX X A compound of formula IX, wherein Ar is as previously defined is reacted with a compo of formula X, wherein R\, R2, n and A are as previously defined. L is hydroxy or a leavi group. SUBSTITUTE SHEET Method 4 XI A compound of formula XI wherein Ar, n, R and R2 are as previously defined is reacted with a compound of formula V, VI, VII, or VIE, to yield a product of formula XII xπ wherein Ar, n, R\, R2 and A are as previously defined. The compound XII is reduced to yield the desired product a compound of formula XIII, Wherein Ar, R\, R2, n and A are as previously defined. SUBSTITUTE SHEET Examples The following examples are intended to illustrate but not limit the scope of the invention, although the compounds named are of particular interest for our intended purposes. These compounds have been designated by a number code, a:b, where a means the number of the example, wherein the preparation of the compound in question is described, and b refers to the order of the compounds prepared according to that example. Thus, compound 1:2 means the second compound prepared according to Example 1. The structures of the compound are confirmed by NMR, masspectra and elementary analysis. When melting points are given, these are uncorrected. Example 1 : 1 l-{3-[Bis-(4-fluorophenyl) amino]propyl}-4-(2-pyridyI)-piperazine dihydrochloride 2.8 g (0.01 mol) of 3-[Bis-(4-p-fluorophenyl)amino]propylchloride, 3.3 g (0.02 mol) of 2-pyridylpiperazine and 0.1 g of iodine was stirred together with 20 ml of toluene at 150° (temperature of oil bath) for 48h. After cooling, the reaction mixture to - 75 °C 50 ml of toluene and 75 ml of water was added. The phases were separated and an aqueous layer was extracted three times with toluene. Evaporation of the solvents yielded the crude base which was purified by flash chromatography and isolated as an oil. 3.2 g of the free base was dissolved in 40 ml of ether. The dihydrochloride was precipitate with excess of hydrochloric acid in ethanol. Recrystallisation in 2-propanol yielded 3.2 g o the titled compound (1 : 1), m.p. 222-224°C. SUBSTITUTE SHEET Example 2: 1 l-{3-(Bis-[4-fluorophenyl)amino]propyI}-4-(3-hydroxy-2-pyridyl)- piperazine, hydrochloride 6.6 g (0.020 mol) of 3-(N-4-Pyridyl-4-fluoroanilino)propylpiperazine, 2.8 g (0.022 mol) of 2-chloro-3-hydroxypyridine and 4.0 g (0.0031 mol) of N-N-diisopropylethylamine was refluxed in xylene for 34 hr under an atmosphere of nitrogen. After cooling, 100 ml of toluene and 100 ml of water were added to the reaction mixture. The phases were separated and the aqueous layer was extracted three times with diethyl ether. Evaporation of the solvents yielded the crude base which was purified by flash chromatography and isolated. The crystals were recrystallised in ethanol: water 1 :1 3 g of the free base was dissolved in 30 ml of ethanol. ethyl acetate 1 :4. The hydrochlorid was precipitated with excess of hydrochloric acid in ethanol. Recrystallisation yielded 2.2 of the titled compound (2:1), m.p. 205-207°C. In essentially the same method was used to prepare following compounds. 2:2 1 - { 3-[Bis(p-fluorophenyl)amino]propyl } -4-pyrimidyl-piperazine hydrochloride m.p. 200-202°C l-{3-(N-4-pyridyI-4-fluoroanilino)propyl}-4-(3-carbamoyl-2-pyridyl)piperazine m.p. 120-121°C 2:4 1 - { 3 -(N-4-pyridyl-4-fluoroanilino)propyl } -4-(5-nitro-2-pyridyl)piperazine 1.5 hydrochloride hemihydrate m.p. 225-228°C 2:5 l-{3-[Bis(p-fluorophenyl)amino]propyl}-4-(3-carbamoyl-2-pyridyl)piperazine dihydrochloride m.p. 226-227°C 2:6 1 - { 3-[Bis(p-fluorophenyl)amino]propyl } -4-(5-nitro-2-pyridyl)piperazine hydrochloride m.p. 210-211°C SUBSTITUTE SHEET 2:7 l-{3-[Bis(p-fluorophenyl)amino]propyl}-4-(2-(methyl-pyridine-3-carboxylate)yl)piperazi hydrochloride m.p. 181-182°C 2:8 l-{3-[Bis(p-fluorophenyl)amino]propyl}-4-(6-chloro-2-pyridyl)piperazine hydrochloride m. p. 193-194°C 2:9 l-{2-[(4,4'-Difluorobenzhydryl)oxy]ethyl}-4-(2-(methyl-pyridine-3-carboxylate)yl) piperazine dihydrochloride m.p. 163-165°C 2:10 l-{3-[Bis(p-fluorophenyl)amino]propyl}-4-(3-nitro-2-pyridyl)piperazine hydrochloride m.p. 170-171°C 2:11 l-{3-[Bis(p-fluorophenyl)amino]propyl}-4-(6-fluoro-2-pyridyl)piperazine hydrochloride m.p. 190-191°C 2:12 l-{2-[(4,4 ' -Difluorobenzhydryl)oxy]ethyl}-4-(6-chloro-2-pyridyl)piperazine hydrochloride m.p. 180-181°C Example 3 : 1 4-{2-[(4.4'-Difluorobcnzhydryl)oxy]ethyl}-l-(2-pyridyI)piperazine dihydrochloride 4.1 g (0.020 mol ) of l-(2-hydroxyethyl)-4-(2-pyridyl)piperazine and 2.4 g (0.010 mol) of 4-fluorobenzhydrylchloride were stirred at 165-170°C (temperature of oil bath) for 45 mi under an atmosphere of nitrogen. After cooling, 60 ml of water and 60 ml of toluene wer added to the reaction mixture. The phases were separated. Evaporation of the organic solvents yielded the crude base which was purified by flash chromatography and isolated an oil. SUBSTITUTE SHEET 2.2 g of the free base was dissolved in 40 ml of ethyl acetate. The dihydrochloride was precipitated with excess of hydrochloric acid in ethanol. Recrystallisation from isopropanol: diethyl ether 3: 1 yielded 1.8 g of the titled compound (3: 1), m.p. 167-168°C Example 4: 1 l-{2-[(4,4VDifluorobenzhydιyI)amino]ethyl}-4-(6-chloro-2-pyridyI)piperazine 2.25 hydrochloride. 6.5 g (0.02 mol) of l-{2-[(4,4'-Difluorobenzhydrilidene)amino]ethyl}piperazine, 3.0 g of (0.021 mol) of 2,6-dichloropyridine, 3.0 g (0.025 mol) of K2CO3 and 0.1 g of iodine were stirred together with 50 ml of xylene at 140°C for 16h After cooling, 100 ml of toluene was added. The solution was filtered and washed three times with water. The organic layer was dried over sodium sulphate, filtered. Evaporation of the solvent yielded 8 g of l-{2-[(4,4'-difluorobenzhydrilidene)amino]ethyl}-4-(6-chloro 2-pyridyl)piperazine as an oil. 8 g (0.018 mol) of the oil was dissolved in 75 ml of methanol and 3.5 g (0.035 mol) of NaBH4 was added and refluxed for 3h. After cooling, 75 ml of water was added and the solvent was extracted with toluene. The organic layer was dried over sodium sulphate, filtrated and concentrated to yield 7.0 g of an oil. The hydrochloride was precipitated with hydrochloric acid in ethanol. Recrystallisation from 2-propanol yielded 5.0 g of the title compound (4: 1), m.p. 235-236°C. In essentially the same method was used to prepare following compounds. 4:2 1 { [2-[(4,4 ' -Difluorobenzhydryl)amino]ethyl } -4-(2-(ethyl-pyridine-3 - carboxylate)yl)piperazine 2.25 hydrochloride m.p. 224°C. (dec.) 4:3 l-{2-[(4,4 ' -Difluorobenzhydryl)amino]ethyl}-4-(3-carboxy-2-pyridyl)piperazine m.p. 229-230°C. SUBSTITUTE SHEET Example 5 This example illustrates the potency of compounds of formula (II) and their therapeuticall active acid addition salts for treatment of mental disorders. Test I. Affinity to 5-HT2 receptors. The binding assay is carried out essentially as described by Leysen et al. (Mol. Pharmacol. 21, 301-14, 1982) using 3 H-ketanserin as ligand. Test 2. Affinity for 5HTι ^-receptors. The binding assay was carried out essentially as described by Peroutka S.J., (Brain Res. 344, 167-171, 1985). Table 1 Affinity to 5-HTo receptors. KjinM) 11 18 Affinity for 5HTJ ^-receptors. Kj fnM) 1.7 SUBSTITUTE SHEET Example 6 The following formulations are representative for all of the pharmacologically active compounds of this invention. Example of a suitable capsule formulation: In case of higher amounts of active ingredients, the amount of lactose used may be reduce Example of a suitable tablet formulation. Solutions for parenteral applications by injection can be prepared in a aqueous solution of water-soluble pharmaceutically acceptable salt of the active substance preferably in a concentration of from about 0.5% to about 5% by weight. These solutions may also cont stabilising agents and/or buffering agents and may conveniently be provided in various dosage unit ampoules. SUBSTITUTE SHEET

Claims: CLAIMS 1. Novel compounds having the general formula (I) wherein Ar are the same or different and selected from wherein R3 is flouro or hydrogen. R] and R2 are the same or different and selected from hydrogen or lower alkyl. n is 2 or 3 X is nitrogen or methine When X is nitrogen, Y is methylene. When X is methine Y is selected from nitrogen or oxygen, preferably oxygen. SUBSTITUTE SHEET A is selected from the following pyrimidyl and pyridyl. R4 and R5 are the same or different and selected from hydrogen, halogen, lower alkyl, electron donor groups such as lower alkoxy or hydroxy, electron acceptor groups such as cyano, nitro, trifluoromethyl, COOR , CONRγRg or CO-B; wherein Rg is hydrogen or lower alkyl; R7 and Rg are the same or different selected from hydrogen, lower alkyl or cycloalkyl; B is selected from ,R 9 — N— - _R a -N O ! ( (cCιHi 2 ):m wherein m is 1, 2, 3, or 4. R9 is selected from hydrogen or lower alkyl, and the pharmacologically active salts thereo 2. Compounds according to claim 1 wherein n is 2. 3. Compounds according to claim 1 or 2, wherein R\ and R2 are hydrogen. SUBSTITUTE SHEET 4. Compounds according to claim 3, wherein A is 5. Compounds according to claim 4 wherein X is nitrogen and Y is methylene. 6. Compounds according to claim 4 wherein X is methine and Y is oxygen. 7. Compounds according to claim 5 or 6, wherein R4 is hydrogen, alkyl. trifluoromethyl, alkoxy, amide, nitro, alkylcarboxylate or cyano and R- is hydrogen, alkyl, alkoxy, nitro, halogen, cyano, alkylcarboxylate or an amide group. 8. Compounds according to claim 7, wherein R4 is hydrogen and R5 is hydrogen, alkyl, alkoxy, nitro, halogen, cyano, alkylcarboxylate or an amide group. 9. A method of preparing compounds having the general formula (I) wherein Ar are the same or different and selected from SUBSTITUTE SHEET wherein R3 is halogen or hydrogen. R\ and R2 are the same or different and selected from hydrogen or alkyl; n is 2 or 3, X is nitrogen or methine When X is nitrogen Y is methylene. When X is methine Y is selected from nitrogen or oxygen. A is selected from the following pyrimidyl or carboxylic derivates. R4 and R5 are the same or different and selected from hydrogen, halogen, lower alkyl, electron donor groups such as lower alkoxy or hydroxy, electron acceptor groups such as cyano, nitro, trifluoromethyl, COORg, COOR Rg or CO-B; wherein Rg is hydrogen or lower alkyl; R7 and Rg are the same or different selected from hydrogen, lower alkyl or cycloalkyl; B is selected from -N O • (Ch-ym wherein m is 1, 2, 3 or 4. R9 is selected from hydrogen or lower alkyl, and the pharmacologi¬ cally active salts thereof wherein a compound having the general formula (II) SUBSTITUTE SHEET Ar \ X — Y— (CH,)!— L / ' Ar π wherein Ar, X and Y are as defined above and L is a leaving group, is reacted with a compound having the general formula (III) R^CI-φn m wherein Ri , R2, n and A are as defined above or wherein a compound having general formula (TV) IN wherein Ar, Rj, R2, X, Y, and n are as previously defined, is reacted with a compound having the formula (V), (VI), (VII) or (VIII) SUBSTITUTE SHEET _ - 20 - VII VIII or wherein a compound having the general formula DC A Arr Ar IX Wherein Ar is as previously defined and L is a leaving group or a hydroxyl, is reacted wit compound of formula X wherein Ri , R2, n and A are as previously defined. 10. Pharmaceutical compositions containing as an active ingredient one or more of the compounds having the general formula (I), preferably together with a pharmaceutically acceptable carrier and, if desired, other pharmacologically active agents. 11. A method of treating a living body suffering from a mental disorder, which comprises the step of administering to said living animal body a compound having the general formula (I). BSTITUTE SHEET

Inventors: ABRAMO LISBETH, BRODSZKI MARTIN, LUNDSTEDT TORBJOERN, NORDVI CURT, OLSSON KNUT GUNNAR, ABRAMO, LISBETH, BRODSZKI, MARTIN, LUNDSTEDT, TORBJOERN, NORDVI, CURT, OLSSON, KNUT, GUNNAR
Applicants: ABRAMO LISBETH, BRODSZKI MARTIN, KABI PHARMACIA AB, LUNDSTEDT TORBJOERN, NORDVI CURT, OLSSON KNUT GUNNAR
Application year: 1993
Main classification: C07D213
IPC codes: A61K31, A61P25, A61P43, C07D213, C07D241