Patent ID: 7169791

Claim:
A compound of formula I wherein R 1 represents hydrogen, lower alkyl, lower alkoxy-lower alkyl, or benzyl; R 2 represents phenyl substituted by one or two substituents selected from the group consisting of lower alkyl, trifluoro-lower alkyl, hydroxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino-lower alkyl, N-cyclohexyl-N-lower alkylamino-lower alkyl, lower alkoxycarbonylpiperidino-lower alkyl, N-lower alkylpiperazino-lower alkyl, lower alkoxycarbonyl-lower alkyl, hydroxy, lower alkoxy, trifluoro-lower alkoxy, 1H-imidazolyl-lower alkoxy, lower alkanoyloxy, benzoyloxy, carboxy, lower alkoxycarbonyl, carbamoyl, lower alkylcarbamoyl, amino, lower alkanoylamino, benzoylamino, amino mono- or disubstituted by lower alkyl, by hydroxy-lower alkyl or by loweralkoxy-lower alkyl, 1H-imidazolyl, lower alkyl-1H-imidazolyl, carboxy-1H-imidazolyl, lower alkyl-estercarboxy-1H-imidazolyl, pyrrolidino, piperidino, piperazino, N-lower alkylpiperazino, morpholino, sulfamoyl, lower alkylsulfonyl, phenyl, pyridyl, halogenyl, or benzoyl; and R 4 represents hydrogen, lower alkyl or halo; or a N-oxide or pharmaceutically acceptable salts thereof.