| abstract |
Compounds of Structure (1): n<CHEM>n in whichn R<1> is H, C1-5 alkyl (straight or branched), or phenyl;n W is a bond, -NHC.HR<6>CO- or -NHCHR<6>CONH-CHR<7>CO-, where R<6> and R<7>, which can be the same or different are H or C1-5 alkyl (straight or branched);n R<2> is H, C1-5 alkyl (straight or branched), aryl or a benzyl group optionally substituted by C1-5 alkyl (straight or branched), C1-4 akoxy (straight or branched) or hydroxy;n R<3> and R<4>, which can be the same or different, are H, C1-5 alkyl (straight or branched) or phenyl, or R<3> and R<4> can together form a 1,4-butylene or 1,5-pentylene group;n R<5> is H or -CHR<8>CONR<9>R<1><0>, where R<8>, R<9> and R<1><0>, which can be the same or different, are H or C1-5 alkyl (straight or branched);n R<1><1> and R<1><2>, which can be the same or different, are H, C1-5 alkyl (straight or branched), or acyl or together with the nitrogen atom shown form a 2-oxo-pyrrolidino group optionally substituted in the 4-position by a hydroxy or C1-5 (straight or branched) alkoxy group, or a 5-oxo-1-imidazolidine group optionally substituted at the 2- position by one or two C1-5 alkyl groups or a 1,4-butylene or 1,5-pentylene group, or optionally substituted at the 4-position by C1-5 alkyl,n or a pharmaceutically acceptable salt thereof, processes and intermediates for making them, pharmaceutical compositions containing them and their use as nootropic agents. |