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Beta-sultams are the sulfonyl analogues of beta-lactams and N-acyl beta-sultams are novel inactivators of the class C beta-lactamase of Enterobacter cloacae P99. The analogous N-acyl beta-lactams undergo enzyme-catalyzed hydrolysis, the rate of which is compatible with significant amide anion expulsion/S-N fission in the transition state, and the enzyme reaction displays a later transition compared with hydrogen-ion-catalyzed hydrolysis of the beta-sultam.

The structural relationship between the active site of [beta]-lactam-recognizing enzymes (BLRE) and amidase signature (AS) enzymes which represent a superfamily of largely bacterial proteins exhibiting bacterial resistance to lactam antibiotics is discussed. The close spatial overlap between the two tetrads might be attributed to a process of convergent evolution driven by a mechanistic imperative.

Raman microscopy is used for studying the reactions between single crystals of the SHV-1 [beta]-lactamase enzyme and the carbapenems, meropenem, imipenem and ertapenem. The studies have shown that mechanism-based inhibitors like carbapenems have behaved differently in the crystalline and solution phase of the SHV-1 [beta]-lactamase.

The synthesis of two new classes of azido- and aziridino-hydroxyl-[beta]-lactam containing structures is presented by means of a stereo- and regioselective epoxide ring opening. The straightforward procedure is useful for the synthesis of potentially bioactive compounds.