Abstract
An analog, 6-(2'-hydroxyethylidene)-4β-methyl-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (11), of the carbapenem β-lactamase inhibitor, asparenomycin A, was synthesized. It possessed a spectrum of antibacterial activity that was comparable to that of asparenomycin A but was less effective as a β-lactamase inhibitor. With ampicillin, it only exhibited a moderate level of synergy against a variety of β-actamase-producing organisms. Although the presence of a 4β-methyl group in the analog brought about a significant increase in chemical stability relative to that of asparenomycin A, it did not result in an increase in stability to kidney dehydropeptidase enzyme.
