Thiophene derivatives

A compound of the formula:

• ##STR4## wherein R.sup.1 is bromo;
• cyano;
• lower alkyl substituted with a substituent selected from the group consisting of hydroxy, amino, acylamino, lower alkylamino, lower alkyl(acyl)amino, acyl, hydroxyimino and lower alkoxyimino;
• lower alkyl substituted with halogen;
• lower alkenyl optionally substituted with cyano;
• acyl;
• nitro;
• amino optionally substituted with substituent(s) selected from the group consisting of acyl and lower alkylsulfonyl;
• sulfo;
• sulfamoyl optionally substituted with lower alkyl, hydroxy;
• or a heterocyclic group other than thienyl and tetrazolyl substituted with substituent(s) selected from the group consisting of hydroxy, oxo, amino and lower alkylamino;
• R.sup.2 is aryl substituted with substituent(s) selected from the group consisting of halogen, lower alkoxy, lower alkylthio, lower alkylsulfinyl, lower alkylsulfonyl, nitro, amino, sulfamoyl and lower alkylsulfonylamino;
• and
• R.sup.3 is aryl substituted with substituent(s) selected from the group consisting of halogen, lower alkoxy, lower alkylthio, lower alkylsulfinyl, lower alkylsulfonyl, nitro, amino, lower alkylamino, acylamino, lower alkyl(acyl)amino, lower alkylsulfonylamino and sulfamoyl;
• provided that
• R.sup.3 is aryl substituted with substituent(s) selected from the group consisting of amino, mono(lower)alkylamino, acylamino, lower alkyl(acyl)amino and sulfamoyl
• when
• R.sup.1 is bromo or cyano, and pharmaceutically acceptable salts thereof.