NZ243336A - 2-aminopyrimidine-4-carboxamide derivative, pharmaceutical compositions - Google Patents

Description

New Zealand Paient Spedficaiion for Paient Number £43336 9 {: 5 3 3 Priority D-usiV,; .

Complete Specification Filed: . cte^s: £p7ia+w.\\^;. l^ublication Date: 139$, P.O. Journal, No: ... ivjTTT! - NEW ZEALAND PATENTS ACT, 1953 riz. fv-yTg^T cnr^E 26 JUK 1032 No.: Date: COMPLETE SPECIFICATION 2 -AMINOPYRIMI DINE—4 -CARBOXAMIDE DERIVATIVES.

THEIR PREPARATION AND THEIR USE IN THERAPEUTICS We, SYNTHELABO, a French body corporate, of 22 avenue Galilee, 92350 Le Plessis-Robinson, France, hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- 24 3336 The invention relates to 2-aminopyrimidine-4-carboxamide derivatives, their preparation and their use in therapeutics.

The invention provides a compound which is a 2-aminopyrimidine carboxamide derivative represented by formula (i) ( <CH2> 2 q "l » A 11 (I) in which X represents hydrogen, fluorine, chlorine, methyl, 1- methylethyl or methoxy, wherein more than one substituent X may be present in which case each X may be the same or different, n represents 2 or 3, m represents l, in which case p represents 1, or else m represents 0, in which case p represents 2, q represents 0 or 1, and represents a hydrogen atom; or a pharmaceutically acceptable acid addition salt thereof.

A compound of the invention may be a pure enantiomer or a mixture of enantiomers, for example a racemate.

The invention also provides a process for preparing a compound of formula (I). ,r"-\ £«< /-N V ■A '^-6 AUG 1993 v\ ft A compound of the invention preferably has one or two substituents X. When one substituent X is present, the substituent is preferably at the 2- or 4- position. When two substituents X are present the substituents are preferably at the 2- and 5- positions.

In accordance with the invention, the compounds of general formula (I) can be prepared according to one of the two processes illustrated by Schemes 1 and 2 which follow. If desired the compounds of general formula (I) can be converted into acid addition salts in a manner known per se. "330 Scheme 1 °\ (CH2>n 0. ,N.

(CH?) (II') (III) (IV.') X (CH2>n" NH, (V») NH, 2'n (VI) (I') Scheme 1 concerns only the compounds of general formula (I) in which m=p=l and g=0, which corresponds to the general formula (I').

According to this scheme, the substituted piperidine 5 of formula (II'} is reacted with a phenoxyalkyl halide of general formula (III), in which X and n are as defined above and Y represents a chlorine or bromine atom, in 2-butanone in the presence of an inorganic base, for example potassium carbonate, at a temperature of 80°C. The acetal obtained is 10 then converted to a ketone of general formula (IV') by hydrolysis, for example with hydrochloric acid.

When all the substituents X are different from halogen atoms, the ketone of general formula (IV') can be converted to an amine of general formula (V') by reaction with ammonia in an 15 aliphatic alcohol, for example methanol, in the presence of 10% palladium on charcoal under a hydrogen atmosphere.

When one of the substituents X is a halogen atom, the ketone of general formula (IV') can be reacted with methoxyamine in aqueous ethanol and the oxime obtained then 20 reduced by an alkali metal hydride, for example lithium aluminium hydride, in an ether solvent such as tetrahydrofuran, to obtain the amine of general formula (V').

The 2-aminopyrimidine-4-carboxamide of general formula (I') is obtained by reacting the amine of formula (V') with 25 2-chloropyrimidine-4-carboxamide of formula (VI), in an aprotic solvent, for example N,N-dimethylformamide, in the presence of an inorganic base, for example potassium carbonate, at a temperature of 20 to 40°C.

The substituted .piperidine of formula (II')/ or < ■ t y / ««, \ , i rj l,4-dioxa-8-azaspiro[4.5]decane, is commercially available.

The phenoxyalkyl halides of general formula (III) can be prepared by methods analogous to those described in J. Pharm. Sci.. 1984, 73/9, 1241-1244, or in Synthesis, 1990, 1069-1071.

The 2-chloropyrimidine-4-carboxamide of formula (VI) can be prepared from 2-chloropyrimidine-4-carbonitrile by treatment with gaseous hydrochloric acid in formic acid, the said nitrile being itself prepared according to the method described in J. Het. Chei. , 1964, 1, 130-133. 10 According to Scheme 2 below, an amine of general formula (II), in which m, p, q and R1 are as defined above and R represents an amine-protecting group, for example a benzyloxycarbonyl or tert-butoxycarbonyl group, is first reacted with a phenoxyalkyl halide of general formula (III), in 15 which X and n are as defined above and Y represents a chlorine or bromine atom, in an aprotic solvent, for example N,N-dimethylformamide, in the presence of a base, for example an inorganic base such as potassium carbonate, at a temperature of 40 to 100°C.

A diamine of general formula (IV) is obtained, which is then deprotected, according to the nature of the protecting group R, by a method analogous to those described in the literature, for example by hydrogenation in the presence of palladium on charcoal (in the case of a benzyloxycarbonyl 25 group) or by reaction with trifluoroacetic acid in dichloromethane (in the case of a tert-butoxycarbonyl group).

A diamine of general formula (V) is obtained, which is finally reacted with 2-chloropyrimidine-4-carboxamide of formula (VI) in an aprotic solvent, for example 24 3336 N,N-dimethylformamide, in the presence of a base, for example an inorganic base such as potassium carbonate, at a temperature of 20 to 60°C.

The protected diamines of general formula (II), in 5 which g represents the number 1, can be prepared by a method analogous to those described for the synthesis of tert-butyl piperidine-4-carbamate (q = 0) in patent applications EP-410278 and EP-417698.

The phenoxyalkyl halides of general formula (III) and 10 2-chloropyrimidine-4-carboxamide of formula (VI) can be prepared as described in connection with Scheme 1.

. ' V .. •<> \ •V - \ c '• \ - 6 AUG 1993 ' 1 A /N Scheme 2 V HN ^ r ^ ^*1 (ID ^1^o/(ch2Vy (III) <CH2Vn-( ' I 0^' U 1 (IV) m (CH2)/ "R /<CH2W() I .NH (V) (£ (CHz>< (VI) >Ik, *1 |j (I) 3 3 3 6 9 The following examples illustrate in detail the preparation of some compounds in accordance with the invention. Elemental microanalyses and IR and NMR spectra confirm the structures of the products obtained. The numbers between 5 parentheses in the headings correspond to those in the table given later.

Example l (Compound No. 1) 2-[l-[2- (2-Methoxyphenoxy) ethyl]piperidin-4-ylamino]pyrimidine-4-carboxamide, hydrochloride. 10 1.1. 8-[2-(2-Methoxyphenoxy)ethyl]-l,4-dioxa-8-azaspiro- bromide, 19.95 g (0.139 mol) of l,4-dioxa-8-azaspiro[4.5]-decane, 28.8 g (0.208 mol) of potassium carbonate and 322 ml of 15 2-butanone are introduced into a 1 litre round bottom flask. The mixture is heated and stirred at the reflux temperature of the solvent for 7 hours. The mixture is cooled, the insoluble material is removed by filtration and the filtrate is concentrated under reduced pressure to give 40.8 g of oil. 20 1.2 l-[2-(2-Methoxyphenoxy)ethyl]piperidin-4-one. l,4-dioxa-8-azaspiro[4.5]decane are dissolved in 408 ml of acetic acid and 40.8 ml of concentrated hydrochloric acid. The mixture is brought to reflux temperature for 30 minutes. The 25 mixture is concentrated under reduced pressure and the residue is then taken up with a little water and dichloromethane. The solution is alkalified with concentrated aqueous ammonia, extracted with dichloromethane, the organic phase is then dried over magnesium sulphate and the solvent evaporated under [4.5]decane. 32.2 g (0.139 mol) of 2-(2-methoxyphenoxy)ethyl 40.8 g (0.139 mol) of 8-[2-(2-methoxyphenoxy)ethyl] u *w \ ■ ^ 0 reduced pressure. The solid obtained is recrystallised from 2-propanol to give 25.4 g of product.

Melting point: 73-75°C. 1.3. 1-[2-(2-Methoxyphenoxy)ethyl]piperidin-4-amine, 5 hydrochloride. .4 g (0.0216 mol) of l-[2-(2-methoxyphenoxy)-ethyl]piperidin-4-one and 200 ml of methanol are introduced into a 500 ml flask of a Parr apparatus. The mixture is cooled in an ice bath, the solution is saturated with ammonia and 10 0.5 g of 10% palladium on charcoal is then added.

The mixture is stirred for 5 hours under a hydrogen atmosphere at ambient pressure, is then filtered and concentrated under reduced pressure.

The hydrochloride of the compound is prepared, which 15 is recrystallised from a 2-propanol/ethyl acetate mixture. 2.2 g of compound are obtained.

Melting point: 128-131°C. 1.4. 2-[l-[2-(2-Methoxyphenoxy)ethyl]piperidin-4-yl-amino]pyrimidine-4-carboxamide, hydrochloride. 2.1 g (0.0073 mol) of l-[2-(2-methoxyphenoxy)- ethyl]piperidin-4-amine, 1.15 g (0.0073 mol) of 2-chloropyrimidine-4-carboxamide and 3 g (0.0219 mol) of potassium carbonate in solution in 42 ml of N,N-dimethyl-formamide are introduced into a 100 ml round bottom flask. 25 The mixture is stirred for 48 hours at room temperature, it is poured into water and then extracted three times with ethyl acetate. The organic phase is washed once with water, dried over sodium sulphate, filtered and the filtrate is concentrated under reduced pressure. The base is recrystallised from 2-propanol to give 0.7 g of base. 19 ml of a 0. IN hydrochloric acid solution in 2-propanol are added to the base in solution in a mixture of dichloromethane and 2-propanol. The solvent is evaporated under 5 reduced pressure and the hydrochloride is recrystallised from 2-propanol. 0.26 g of compound are obtained.

Melting point: 194-196*C.

Example 2 (Compound No. 2) 2-[l-[2-(4-Fluorophenoxy)ethyl]piperidin-4-ylamino]pyrimidine-10 4-carboxamide, hydrochloride. 2. l 8- [2- (4-Fluorophenoxy) ethyl]-l, 4-dioxa-8-azaspiro-[4.5]decane. 21.91 g (0.1 mol) of 2-(4-fluorophenoxy)ethyl bromide, 14.32 g (0.1 mol) of l,4-dioxa-8-azaspiro[4.5]decane and 15 20.73 g (0.15 mol) of potassium carbonate are introduced into 250 ml of 2-butanone and the mixture is heated at boiling for 7 hours.

The mixture is cooled to room temperature, filtered, the insoluble material washed with 200 ml of ether and the 20 solvents evaporated under reduced pressure. 29 g of a yellow oil are obtained which is used as it is in the following stage. 2.2. 1- [2- (4-Fluorophenoxy) ethyl ]piperidin-4-one. ml of concentrated hydrochloric acid are added to a solution of 28.13 g (0.1 mol) of 8-[2-(4-fluorophenoxy)ethyl]-25 l,4-dioxa-8-azaspiro[4.5]decane in 300 ml of acetic acid. The mixture is heated for 1 hour at boiling, is evaporated under reduced pressure, the residue is treated with 150 ml of IN sodium hydroxide solution and is extracted with dichloromethane. The organic phase is dried over magnesium 12 sulphate, filtered and the solvent evaporated under reduced pressure. 24.9 g of product are obtained which is used as it is in the following stage. ethyl]piperidin-4-one, 10.65 g (0.1275 mol) of methoxyamine hydrochloride and 11.51 g (0.140 mol) of sodium acetate are placed in 300 ml of ethanol and 80 ml of water and the mixture is heated for 2 hours. and the mixture is extracted with dichloromethane. The organic phase is dried over magnesium sulphate, filtered and evaporated under reduced pressure. 4.84 g (0.127 mol) of lithium aluminium hydride are 15 suspended in 150 ml of tetrahydrofuran and then the crude product obtained previously is added dropwise. The mixture is heated at reflux temperature for 18 hours.

The excess hydride is hydrolysed with 5 ml of sodium hydroxide solution, the mixture is filtered on magnesium 20 sulphate and the solvent evaporated under reduced pressure. The residue is taken up with water, 100 ml of 2N sodium hydroxide solution are added and the mixture is extracted with dichloromethane. The organic phase is dried over magnesium sulphate, filtered and the solvent evaporated. The compound is 25 obtained in the base form.

The hydrochloride is prepared by adding a 0.1N hydrochloric acid solution in 800 ml of 2-propanol. 9.93 g of compound are obtained.

Melting point: 159-162*C. 2.3. l-[2-(4-Fluorophenoxy)ethyl]piperidin-4-amine. .15 g (0.085 mol) of l-[2-(4-fluorophenoxy)- The ethanol is evaporated, 100 ml of water are added 4"" a 5 - 13 - ' 2.4. 2-[1-[2-(4-Fluorophenoxy)ethyl]piperidin-4-ylamino]-pyrimidine-4-carboxamide, hydrochloride. .5 g (0.02 mol) of l-[2-(4-fluorophenoxy)ethyl]-piperidin-4-amine, 3.15 g (0.02 mol) of 2-chloropyrimidine-5 4-carboxamide, 6.91 g (0.05 mol) of potassium carbonate and 0.4 g of sodium iodide are suspended, under argon, in 40 ml of N,N-dimethylformamide.

The mixture is stirred at room temperature for 17 hours and then at 40-45°C for 8 hours. The mixture is cooled to 10 room temperature, poured into 150 ml of water and extracted with ethyl acetate. The organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure. After chromatography on silica (eluent: dichloromethane/methanol 97.5/2.5 to 90/10), 15 4.95 g of base are obtained.

The hydrochloride is prepared from it by reaction with a 0.1N hydrochloric acid solution in 2-propanol. After recrystallisation from ethanol, 4.1 g of compound are obtained. Melting point: 202-205"C.

Example 3 (Compound No. 8) 2-[[[l-[2-(4-Fluorophenoxy)ethyl]piperidin-4-yl]methyl]-amino]pyrimidine-4-carboxamide, fumarate. 3.1. 1,1-Dimethylethyl [[l-[2-(4-fluorophenoxy)ethyl]~ piperidin-4-yl]methyl]carbamate. 25 6.8 g (0.031 mol) of 2-(4-fluorophenoxy)ethyl bromide, 6.0 g (0.028 mol) of l,l-dimethylethyl [(piperidin-4-yl)methyl]carbamate, 5.8 g of potassium carbonate and 60 ml of N,N-dimethylformamide are introduced into a 250 ml, three-necked round bottom flask and the mixture is heated at ^ ■ between 90 and 100*c for 8 hours under an argon atmosphere.

The mixture is cooled to room temperature, poured into 250 ml of water and extracted with ethyl acetate. The organic phase is washed with water, dried over magnesium sulphate, 5 filtered and the solvent evaporated under reduced pressure.

After purification by chromatography on a silica gel column (eluent: dichloromethane/methanol 98/2 to 92/8), 9 g of oily product are isolated which is used as it is in the following stage. 3.2. l-[2-(4-Fluorophenoxy)ethyl]piperidine-4-methenamine. 8.8 g (0.025 mol) of 1,1-dimethylethyl [[ 1- [2-(4-fluorophenoxy)ethyl]piperidin-4-yl]methyl]carbamate, 90 ml of dichloromethane and 90 ml of trifluoroacetic acid are introduced into a 500 ml, three-necked round bottom flask and 15 the mixture is heated at 40eC for 4.5 hours.

The mixture is concentrated under reduced pressure, the crude residue is treated with 200 ml of IN sodium hydroxide solution and the mixture is extracted with dichloromethane.

The organic phase is washed with water, dried over 20 magnesium sulphate, filtered and the solvent evaporated under reduced pressure. 6.2 g of yellow oil are obtained which is used as it is in the following stage. 3.3. 2 — [[[1—[2 —(4-Fluorophenoxy)ethyl]piperidin-4-yl]-25 methyl]amino]pyrimidine-4-carboxamide, fumarate.

A suspension of 3.1 g (0.0123 mol) of 1-[2-(4-fluorophenoxy)ethyl]piperidine-4-methenamine, 2.0 g (0.0127 mol) of 2-chloropyrimidine-4-carboxamide, 2.55 g (0.0185 mol) of potassium carbonate, 0.3 g of sodium iodide and $ W - 15 - 65 ml of N,N-dimethyIformamide is prepared under an argon atmosphere and the mixture is heated at 60#C for 7.5 hours.

The mixture is cooled to room temperature, poured into 150 ml of water, extracted with ethyl acetate, the organic 5 phase is washed with water, dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure. The residue is taken up with diethyl ether and 3.5 g of base are obtained.

The fumarate is prepared by addition of 1.07 g 10 (0.009 mol) of fumaric acid, in solution in 100 ml of ethanol, to 3.45 g (0.009 mol) of base, in solution in 200 ml of ethanol. The solvent is evaporated under reduced pressure and the residue is recrystallised from 2-propanol. 2.9 g of acid fumarate are finally obtained.

Melting point: 167-169.5°C.

Example 4 (Compound No. 10) 2-[[[l-[2-(2-Methoxyphenoxy)ethy1]piperidin-3-yl]methyl]-amino]pyrimidine-4-carboxamide, fumarate. 4.1. l,l-Dimethylethyl [[1-[2-(2-methoxyphenoxy)ethylJ-2 0 piperidin-3-y1]methyl]carbamate. 4.62 g (0.02 mol) of 2-(2-methoxyphenoxy)ethyl bromide, 4.29 g (0.02 mol) of 1,1-dimethylethyl [(piperidin- 3-yl)methyl]carbamate, 3.32 g (0.024 mol) of potassium carbonate and 40 ml of N,N-dimethylformamide are introduced into a 150 ml Keller flask and the mixture is heated at between 80 and 90"C for 6 hours under an argon atmosphere. The mixture is cooled to room temperature, poured into 500 ml of water and extracted with ethyl acetate. The organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent ■"j % '"'i is evaporated under reduced pressure.

The residue is taken up with petroleum ether and 6.8 g of solid are obtained which is used as it is in the following stage.

Melting point: 78-79'C. 4.2. l-[2-(2-Methoxyphenoxy)ethyl]piperidine-3-methenamine. 6.8 g (0.0186 mol) of 1,1-dimethylethyl [[l-[2-(2-methoxyphenoxy)ethy1]piperidin-3-yl]methyl]carbamate, 55 ml of dichloromethane and 55 ml of trifluoroacetic acid are 10 introduced into a 250 ml round bottom flask and the mixture is heated at 40"C for 4.5 hours.

The mixture is concentrated under reduced pressure, the crude residue is treated with 200 ml of IN sodium hydroxide solution and the mixture is extracted with dichloromethane. 15 The organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure. 4.76 g of yellowish oil are obtained which is used as it is in the following stage. 20 4.3. 2-[[[l-[2-(2-Methoxyphenoxy)ethyl]piperidin-3-yl]- methyl]amino]pyrimidine-4-carboxamide, fumarate.

A suspension of 4.76 g (0.018 mol) of 1-[2-(2-methoxyphenoxy)ethyl]piperidine-3-methenamine, 2.84 g (0.018 mol) of 2-chloropyrimidine-4-carboxamide, 3 g 25 (0.0216 mol) of potassium carbonate, 0.3 g of sodium iodide and 36 ml of N,N-dimethylformamide is prepared under an argon atmosphere and the mixture is stirred at room temperature for 24 hours.

The mixture is poured into 50s0 ml of water, extracted 3 3 17 with ethyl acetate, the organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure.

After purification of the residue by chromatography on a silica gel column (eluent: dichloromethane/ methanol 98/2 to 90/10), 4.4 g of base are finally isolated. (0.0114 mol) of fumaric acid, in solution in 100 ml of ethanol, to 4.4 g (0.0114 mol) of base, in solution in 100 ml of 10 ethanol. The solvent is evaporated under reduced pressure and the residue is recrystallised from a mixture of 2-propanol and ethanol. 2.65 g of acid fumarate are finally obtained.

Melting point: 154-156#C.

Example 5 (Compound No. 4) 15 2-[1-[2-[5-Methyl-2-(1-methylethyl)phenoxy]ethyl]piperidin-4-ylamino]pyrimidine-4-carboxamide, fumarate. 5.1. 1,1-Dimethylethyl [l-[2-[5-methyl-2-(1-methylethyl)- ethyl)phenoxy]ethyl bromide, 3.87 g (0.0193 mol) of 1,1-dimethylethyl (piperidin-4-yl)carbamate, 4.0 g (0.029 mol) of potassium carbonate and 40 ml of N,N-dimethylformamide are introduced into a 250 ml, three-necked round bottom flask and the mixture is heated at between 90 and 100"C for 8 hours under 25 an argon atmosphere. 200 ml of water and extracted with ethyl acetate. The organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent, evaporated under reduced pressure. The The fumarate is prepared by addition of 1.33 g phenoxy]ethyl]piperidin-4-y1]carbamate. .48 g (0.0231 mol) of 2-[5-methyl-2-(l-methyl- The mixture is cooled to room temperature, poured into residue is purified by chromatography on a silica gel column by eluting with a 98/2 to 95/5 dichloromethane/methanol mixture. 7.1 g of amorphous solid are obtained which is used as it is in the following stage. 5.2. l-[2-[5-Methyl-2-(l-methylethyl)phenoxy]ethyl]-piperidin-4-amine. 7.0 g (0.0186 mol) of 1,l-dimethylethyl [l-[2-[5-methyl-2-(1-methylethyl)phenoxy]-ethyl]piperidin-4-yl]carbamate, 70 ml of dichloromethane and 70 ml of 10 trifluoroacetic acid are introduced into a 250 ml, three-necked round bottom flask and the mixture is heated at 40"C for 4 hours.

The mixture is diluted with 150 ml of dichloromethane, cooled to 0°C, and a stream of gaseous ammonia is passed 15 through it. The insoluble material is removed by filtration, the solvent is evaporated under reduced pressure, the residue is taken up with dichloromethane, the solution is dried over magnesium sulphate, filtered and evaporated under reduced pressure. 5.05 g of orange-coloured oil are obtained which is used as it is in the following stage. .3. 2-[l-[2-[5-Methyl-2-(1-methylethyl)phenoxy]ethyl]-piperidin-4-ylamino]pyrimidine-4-carboxamide, fumarate.

A suspension of 3.4 g (0.0123 mol) of l-[2-[5-methyl- 2-(l-methylethyl)phenoxy]ethyl]-piperidin-4-amine, 2.0 g (0.0127 mol) of 2-chloropyrimidine-4-carboxamide, 2.55 g (0.0185 mol) of potassium carbonate, 0.3 g of sodium iodide and 65 ml of N,N-dimethylformamide is prepared under an argon * 1 J <L. ' atmosphere and the mixture is heated at 60 *C for 7.5 hours.

The mixture is cooled to room temperature, poured into 150 ml of water, extracted with ethyl acetate, the organic phase is washed with water, dried over magnesium sulphate, 5 filtered and the solvent evaporated under reduced pressure. The residue is taken up with diethyl ether, which provides 3.4 g of base which are recrystallised from toluene to give 2.6 g of white solid.

Melting point: 157.5-160°C. in order to prepare the fumarate from it, it is dissolved in 150 ml of ethanol and 0.76 g (0.0064 mol) of fumaric acid in solution in 100 ml of ethanol is added, the solvent is evaporated under reduced pressure and the residue is recrystallised from methanol. 3.6 g of acid fumarate are finally obtained.

Melting point: 241-244°C.

Example 6 (Compound No. 5) 2-[1-[3-(5-Fluoro-2-methoxyphenoxy)propyl]piperidin-4-ylamino]pyrimidine-4-carboxamide, fumarate. 20 6.1. 1,1-Dimethylethyl [l-[3-(5-fluoro-2-methoxyphenoxy)-propyl]piperidin-4-yl]carbamate. 6.35 g (0.0241 mol) of 3-(5-fluoro-2-methoxyphenoxy) propyl bromide, 4.37 g (0.0218 mol) of 1,1-dimethylethyl (piperidin-4-yl)carbamate, 4.5 g of potassium 25 carbonate and 45 ml of N,N-dimethylformamide are introduced into a 250 ml, three-necked round bottom flask and the mixture is heated at between 90 and 100"C for 8.5 hours under an argon atmosphere.

The mixture is cooled to room temperature, poured into $ 3 3 3 6 250 ml of water and extracted with ethyl acetate. The organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure. The residue is purified by chromatography on a silica gel column by 5 eluting with a 97/3 to 92/8 dichloromethane/methanol mixture. 7.3 g of amorphous solid are obtained which is used as it is in the following stage. 6.2. 1- [ 3 - (5-Fluoro-2 -methoxyphenoxy) propyl ]piperidine-4-amine. 5.7 g (0.0149 mol) of 1,1-dimethylethyl [1-[3-(5-fluoro-2-methoxyphenoxy)propyl]piperidin-4-yl]-carbamate, 60 ml of dichloromethane and 60 ml of trifluoroacetic acid are introduced into a 250 ml, three-necked round bottom flask and the mixture is heated at 40"C for 4 15 hours.

The mixture is diluted with 200 ml of dichloromethane, cooled to 0°C and a stream of gaseous ammonia is passed through it. The insoluble material is removed by filtration, the solvent is evaporated under reduced pressure, the residue is 20 taken up with dichloromethane, the solution dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure. 4.1 g of orange-coloured oil are obtained which is used as it is in the following stage. 25 6.3. 2-[l-[3-(5-Fluoro-2-methoxyphenoxy)propyl]piperidin-4-ylamino]pyrimidine-4-carboxamide, fumarate.

A suspension of 3.5 g (0.0123 mol) of l-[3-(5-fluoro-2-methoxyphenoxy)propyl]piperidin-4-amine, 2.0 g (0.0127 mol) of 2-chloropyrimidine-4-carboxamide, 2.55 g (0.0158 mol) of 243336 potassium carbonate, 0.3 g of sodium iodide and 65 ml of N,N-dimethylformamide is prepared under an argon atmosphere and the mixture is heated at 60*C for 7 hours.

The mixture is cooled to room temperature, poured into 150 ml of water, extracted with ethyl acetate, the organic phase is washed with water, dried over magnesium sulphate, filtered and the solvent evaporated under reduced pressure. The residue is taken up with diethyl ether and 3.3 g of base are obtained which are recrystallised from toluene to give 2.55 g of solid.

The latter is dissolved in 150 ml of ethanol, 0.74 g (0.00632 mol) of fumaric acid in solution in 80 ml of ethanol are added, the solvent is evaporated under reduced pressure and the residue is recrystallised from methanol. 2.5 g of acid fumarate are finally obtained.

Melting point: 244.5-247°C. 4 3 3 The following table structures and the physical according to the invention. illustrates the chemical properties of some compounds Table <CH2>^n,( >» I I1 ^ .A.

(I) 'NH, No.

X n m,p q * Salt M.p. (®C) 1 2-OCH3 2 1,1 0 H HCl 194-196 2 4-F 2 1,1 0 H HCl 202-205 3 2-OCH3, 5-F 2 1,1 0 H fum 211-213.5 4 2-iC3H7, 5-CH3 2 1,1 0 H fum 241-244 2-OCH3, 5-F 3 1,1 0 H fum 244.5-247 6 4-F 3 1,1 0 H fum 239-241 7 B 2 0,2 1 H fum 167.5-170 8 4-F 2 1,1 1 H fum 167-169.5 9 4-F 2 0,2 1 H ffum 170-173 2-0(3% 2 0,2 1 H fum 154-156 11 2-OCH3, 5-CI 2 1,1 1 H fum 172.5-175 Note: in column "X", "iCjH/' denotes a 1-methylethyl group; in column "Salt", "HCl" denotes a hydrochloride, "fum." denotes a hydrogen fumarate (1 mole of base per 1 mole of diacid) and "jfum." denotes a fumarate composed of 2 moles of base and 3 moles of diacid. * 4 3 3 3 The compounds of the invention were made the subject of studies regarding their antagonist activity of c^-adrenergic receptors at the level of the lower urinary apparatus.

Their in vitro activity was studied on isolated rabbit urethra.

Adult rabbit urethra rings are prepared according to the method of Ueda et al.# Eur. J. Pharmacol.. (1984), 103, 249-254, and then, after sensitisation to noradrenalin, the concentration-response curve to phenylephrine is determined in 10 the absence and in the presence of the study compound.

The potency of the a^-adrenergic antagonism of each compound is evaluated by calculation of the pA2, the antilogarithm of the molar concentration of the antagonist in the presence of which the concentration of the agonist must be 15 doubled to cause the same effect as in its absence.

The pA2 values of the compounds are of the order of 5.5 to 9.

The in vivo activity of the compounds of the invention was studied with regard to their effect on the urethral 20 hypertonia caused by the stimulation of the sympathetic fibres of the hypogastric nerve in anaesthetized cat.

Adult male cats are anaesthetized by sodium pentobarbital and they are prepared according to the method of Theobald, J. Auton. Pharmac., (1983), 3, 235-239, in order to obtain a urethral hypertonia by stimulation of the sympathetic fibres of the hypogastric nerve. The contractile responses of the urethra to the electrical stimulation of the hypogastric nerve are recorded before and after intravenous administration of the study compounds, at cumulative doses from 1 to sps =7 =7 T ./ —i 4 r v, {•• 1000 /xg/kg.

The strength of the c^-adrenergic antagonism of each compound is evaluated by calculation of the IDS0, the dose which inhibits by 50% the urethral hypertonia.

The ID50 values of the compounds of the invention are of the order of 0.01 to 1 mg/kg.

The results of the tests show that the compounds of the invention show, in vitro, an antagonist activity of the 0,,-adrenergic receptors of the smooth muscles of the lower 10 urinary apparatus (urethra) stimulated by an ^-adrenergic agonist (phenylephrine). In vivo, they inhibit the urethral hypertonia caused by sympathetic nervous stimulation.

The invention therefore includes compounds of the invention for use as active therapeutic substances, and 15 particularly compounds of the invention for use as a-adrenergic receptor antagonists.

The compounds of the invention can thus be used for the symptomatic treatment of diseases and complaints which involve a hyperactivity of the a-adrenergic system at the level 20 of the lower urinary apparatus, and especially for the treatment of benign hypertrophia of the prostate, of dysuria and of pollakiuria.

The invention includes pharmaceutical compositions comprising a compound of the invention and a pharmaceutically 25 acceptable carrier or diluent.

Compounds of the invention can be introduced in all forms appropriate for enteral or parenteral administration, combined with pharmaceutical excipients, for example in the form of tablets, sugar- coated pills, gelatin capsules, 24 3 3 3 6 capsules, drinkable or injectable solutions or suspensions, or suppositories, the charges being such as to allow a daily dose from 0.5 to 500 mg of active substance. h • *

Claims (13)

WHAT WE CLAIM IS: \lQD£C^93 / V,-?1-. .... .' $n'"

1. A compound which is a 2-aminopyrimidine carboxamide derivative represented by formula (I) (C"2W( V 'N I ()m <C[I2> (I) 15 n m m q Ri 10 in which X represents hydrogen, fluorine, chlorine, methyl, 1- methylethyl or methoxy, wherein more than one substituent X may be present in which case each X may be the same or different, represents 2 or 3, represents 1, in which case p represents 1, or else represents 0, in which case p represents 2, represents 0 or 1, and represents a hydrogen atom; 20 or a pharmaceutically acceptable acid addition salt thereof.

2. A compound according to claim 1 which is a pure enantiomer or a mixture of enantiomers.

3. A compound according to claim 1 or 2 wherein one or two substituents X, wherein X is other than hydrogen, are present.

4. A compound according to claim 3 wherein one substituent X, wherein X is other than hydrogen,is present at the 2- or" 4-. position.

5. A compound according to claim 3 wherein two substituents X, wherein X is other than hydrogen, are present at the .2-r:and--5- positions.

6. A compound according to claim 1 specifically - 27 - identified herein.

7. A process for the preparation of a compound as claimed in any one of the preceding claims, which process comprises reacting a diamine of formula (V) ()m " (ch2) 10 I1 NH (v) in which X, n, m, p, q and R, are as defined in claim 1, with 2-chloropyrimidine-4-carboxamide in an aprotic solvent and in the presence of a base, and optionally converting the resulting 15 compound of formula (I) into an acid addition salt thereof.

8. A process according to claim 7 wherein the diamine of formula (V) is produced by reacting an amine of formula (II) 20 J ^ HN Ps I '( ), m I1 <CHZ>q'N^R (II) 25 in which m, p, q and R, are as defined in claim 1 and R represents an amine-protecting group, with a phenoxyalkyl halide of formula (III) 243 3 3 6 - 28 - (III) 5 in which X and n are as defined in claim 1 and Y represents chlorine or bromine, in an aprotic solvent and in the presence of a base, to thereby obtain a diamine of formula (IV) 10 / (CHp) ( ) N X I (IV) (L <CH2>< .R in which X, m, n, p, q, R and R1 are as defined above, which diamine is then deprotected. 15

9. A process for producing a compound as claimed in claim 1 substantially as described in any one of Examples 1 to 6.

10. A compound as claimed in any one of claims 1 to 6 whenever prepared by a process as claimed in any one of 20 'claims 7 to 9.

11. A compound as claimed in any one of claims 1 to 6 and 10, for use as an active therapeutic substance.

12. A compound according to claim 11, for use as an c^-adrenergic receptor antagonist. 25

13. A pharmaceutical composition comprising a compound as claimed in any one of claims 1 to 6 and 10, and a pharmaceutically acceptable carrier or diluent. °^\ ^-pfc.bb.Q„. V ± By the authorised agents \ A J PARK £7S0N Per 6Ab'G1995/