6-(Substituted methylene)penems, potent broad spectrum inhibitors of bacterial .BETA.-lactamase. II. Racemic furyl and thienyl derivatives.

Abstract
A series of racemic 6-(substituted methylene)penems have been prepared. The compounds contain a 5-membered monoheteroaromatic ring at C-8. The antibacterial/synergistic and .beta.-lactamase inhibitory activities of both E- and Z-isomers and 2-substituted derivatives are compared.