Patent ID: 7732473

Claim:
A process for the preparation of compounds of the general formula (I) wherein: A is selected from the group consisting of carbocyclic aromatic groups, heterocyclic aromatic groups, and arylC 1-4 alkyl; R 1 is selected from the group consisting of: hydrogen, arylC 1-7 alkyl, optionally substituted on the aryl moiety with one or more groups chosen among hydroxy, C 1-4 alkoxy, halogen, haloC 1-4 alkyl; heterocyclylC 1-7 alkyl, optionally substituted on the heterocyclyl moiety with one or more groups chosen among C 1-4 alkyl and hydroxy; and C 1-7 alkyl, optionally interrupted by an oxygen or sulphur atom or optionally substituted at any position by one or more groups chosen among hydroxy, thio, amino, carboxyl, aminocarbonyl, guanidinyl; R 2 is selected from the group consisting of hydrogen, C 1-4 alkyl, arylC 1-4 alkyl and phenyl; or else R 1 and R 2 , taken together, form a saturated carbocyclic ring containing from 3 to 8 carbon atoms; R 3 is selected from the group consisting of hydrogen, C 1-4 alkyl, arylC 1-4 alkyl, CONH 2 and COOR 5 in which R 5 is selected from the group consisting of hydrogen and C 1-4 alkyl; R 4 is selected from the group consisting of hydrogen, C 1-4 alkyl, aryl, arylC 1-4 alkyl and heterocyclyl; n is 2, 3 or 4; in the form of a racemic mixture or in the form of enantiomers, and pharmaceutically acceptable salts thereof, comprising the following stages: i) reacting an aminoacid of formula (IV) or of one of its activated derivatives with a compound of formula (V) A-NH 2 (V) to obtain a compound of formula (VI): in which R 1 , R 2 and A are as defined above, and P is H or a suitable protective group; ii) reacting the compound of formula (VI) obtained in stage i) with a compound of formula (VII) to obtain a compound of formula (VIII) in which A, R 1 , R 2 , R 3 , R 4 and n are as defined above, P is defined as above, and R′ is an alkyl group; iii) optionally removing the protective group P by means of hydrogenolysis of the compound of formula (VIII) obtained from stage ii), to obtain the corresponding compound (VIII), in which P is H; and iv) cyclizing of the compound of formula (VIII), in which P is H coming from stage ii) or from stage iii), to obtain the desired compound of formula (I).