Further Studies on the Synthesis of Thienamycin: a Facile and Stereoselective Synthesis of a Bicyclic β-Keto Ester by 1,3-Dipolar Cycloaddition
A potential compound, ethyl 6-*)-1-hydroxyethyl>-3,7-dioxo-1-azabicycloheptane-2-carboxylate (18), for the synthesis of thienamycin (1), was stereoselectively prepared by 1,3-dipolar cycloaddition of the nitrone (12) and benzyl crotonate as a key reaction.