Abstract: Sulfonamide derivatives of the formula I ##STR1## where R.sup.1 is a C.sub.1 -C.sub.4 -alkyl or phenyl group which may be substituted by halogen, trifluoromethyl or C.sub.1 -C.sub.4 -alkyl, R.sup.2 is hydrogen or C.sub.1 -C.sub.4 -alkyl, A is a group CHOR.sup.3 C.dbd.O, C.dbd.S or C.dbd.N--OR.sup.4, R.sup.3 is hydrogen, C.sub.1 -C.sub.4 -alkyl phenyl, benzyl or C.sub.1 -C.sub.4 -acyl, R.sup.4 is hydrogen or methyl, B may be methylene or ethylene in the m or p position or, of A is not carbonyl, may be methyleneoxy, the oxygen atom being bonded to the aromatic, and E is a carboxyl, phosphonic acid or sulfo radical, their physiologically acceptable salts, esters with C.sub.1 -C.sub.4 -alcohols or amides or the tetrazol-5-yl radical, their preparation and their use as drugs.