Studies on novel carbacephem analogs: synthesis of 7-methoxy-homo-PS-5 and a 7-methoxy-8-epi-homothienamycin intermediate

The synthesis of two carbacephems bearing a 7-methoxy group and either an additional ethyl (PS-5) or hydroxyethyl (thienamycin) side chain has been completed. Rhodium carbenoid insertion methodology was used to generate the bicyclic ring systems.