Substituted imidazo[1,5-A]pyridine derivatives and other substituted bicyclic derivatives, useful as aromatase inhibitors

A compound of the formula ##STR30## wherein n denotes 0, 1, 3 or 4;

• R.sub.1 represents hydrogen, lower alkyl;
• lower alkyl substituted by hydroxy, lower alkoxy, lower alkanoyloxy, lower alkanoyl, amino, lower alkylamino or di-lower alkylamino, halogen, sulfo, sulfamoyl, carboxy, lower alkoxycarbonyl, carbamoyl or cyano;
• nitro, halogen, hydroxy, lower alkoxy, aryloxy, aryl-lower alkoxy, lower alkanoyloxy, aroyloxy, lower alkoxycarbonyloxy, mercapto, lower alkylthio, arylthio, aryl-lower alkylthio, aryl-sulfinyl, aryl-sulfonyl, lower alkyl-sulfinyl, lower alkylsulfonyl, lower alkanoylthio, amino, lower alkylamino, arylamino, aryl-lower alkylamino, lower alkanoylamino, aroylamino, di-lower alkylamino;
• pyrrolidino, piperidino, morpholino, thiomorpholino or optionally 4-lower alkylsubstituted piperazino;
• quaternary ammonium derived from a disubstituted amino group mentioned above which contains as quaternary substituent lower alkyl, hydroxy- or halo-lower alkyl or aryl-lower alkyl;
• sulfo, lower alkoxysulfonyl, sulfamoyl, lower alkylsulfamoyl, di-lower alkylsulfamoyl, formyl or formyl as a di-lower alkyl acetal derivative;
• iminomethyl which may be N-substituted by hydroxy, lower alkoxy, lower alkanoyloxy, lower alkyl, aryl or amino;
• C.sub.2 -C.sub.20 -alkanoyl, halo-C.sub.2 -C.sub.7 -alkanoyl, aroyl, cyano, carboxy, lower alkoxycarbonyl, carbamoyl, lower alkylcarbamoyl, di-lower alkylcarbamoyl or hydroxycarbamoyl;
• R.sub.2 represents hydrogen, lower alkyl;
• lower alkyl substituted by aryl, carboxy or lower alkoxycarbonyl;
• hydroxy, lower alkoxy, aryloxy, aryl-lower alkoxy, lower alkanoyloxy, aroyloxy, lower alkoxycarbonyloxy, mercapto, lower alkylthio, arylthio, aryl-lower alkylthio, aryl-sulfinyl, aryl-sulfonyl, lower alkylsulfinyl, lower alkylsulfonyl, lower alkanoylthio, C.sub.2 -C.sub.20 -alkanoyl, halo-C.sub.2 -C.sub.7 -alkanoyl, aroyl, cyano, carboxy, lower alkoxycarbonyl, carbamoyl, lower alkyl-carbamoyl, di-lower alkylcarbamoyl or hydroxycarbamoyl;
• aroyl within said definitions represents arylcarbonyl;
• and aryl within any of the above definitions represents 1- or 2-naphthyl, phenyl, or phenyl substituted by lower alkyl, lower alkoxy or halogen;
• or a pharmaceutically acceptable salt thereof.