Synthesis and beta-lactamase inhibitory activity of new 6 beta-sulfonamidopenicillanic acids.

New 6 beta-aryl(alkyl)sulfonamidopenicillanic acids and their sulfoxides were synthesized by sulfonylation of 6 beta-aminopenicilanic acid or its beta-sulfoxide with an appropriate sulfonyl chloride. The corresponding 6 beta-sulfonamidopenicillanic acids sulfones were prepared by oxidation of the sulfoxides with potassium permanganate in aqueous medium. The obtained compounds reduced the minimum inhibitory concentrations of ampicillin against 8 reference and 7 clinically isolated strains.