Substituted 1-sulfonylbenzimidazoles

A compound of the formula ##STR3## wherein R.sub.1 is R.sub.4 R.sub.5 NH-, wherein R.sub.4 and R.sub.5 are independently C.sub.1 -C.sub.3 alkyl and when taken together with the nitrogen atom to which they are attached, are pyrrolidino, piperidino or morpholino;

• R.sub.2 is hydrogen, formyl, acetyl or propionyl;
• R.sub.3 is C.sub.1 -C.sub.8 alkoxycarbonyl, allyloxycarbonyl, propargyloxycarbonyl, (C.sub.3 -C.sub.7 cycloalkyl)oxycarbonyl, (C.sub.3 -C.sub.7 cycloalkyl)methyloxycarbonyl, 1-(C.sub.3 -C.sub.7 cycloalkyl) ethyloxycarbonyl, benzyloxycarbonyl, .alpha.-methylbenzyloxycarbonyl, phenoxycarbonyl, hydrazinocarbonyl, carboxy, carboxamido, N-(C.sub.1 -C.sub.4 alkyl)carboxamido, N-(C.sub.1 -C.sub.4 alkoxy)carboxamido or cyano;
• and R.sub.3 is at the 5 or 6 position.