The interaction of chlorinated 6-spiroepoxypenicillins with Bacillus cereusβ-lactamase I: irreversible inhibition and turnover

Abstract

The chlorinated 6-spiroepoxypenicillin anilides (1a) and (1b) are irreversible inhibitors of β-lactamase I from Bacillus cereus, but they are also turned over by this enzyme to yield the same hydrolysis product, whose structure has been revealed to be an unusual 6-substituted-1,4-dihydrothiazine-3-carboxylate, α-ketoamide; a possible pathway for the turnover and inhibitory processes associated with these interactions is presented.