β-sultams - Mechanism of reactions and use as inhibitors of serine proteases

β-Sultams are reactive sulfonyl analogues of β-lactams and show enormous rate enhancements over analogous reactions of sulfonamides. N-Acyl β-sultams undergo S-N rather than C-N fission, although α-alkenyl substituents direct nucleophilic attack to the acyl center. They also inactivate serine enzymes such as elastase and β-lactamase by sulfonylation of the active site serine. Structure-activity relationships are used to identify differences in transition state structures.