ChemInform Abstract: Stereocontrolled Synthesis of 4-Acetoxy-2-azetidinone via Double Azetidinone Ring Formation: A Useful Precursor of Carbapenem and Penem Antibiotics.

HeeAn Kwon, MiJung Lee, InHee Lee, SuJin Lee, TaekHyun Yoon, and TaeSeop Hwang*Choongwae Research Laboratory, Choongwae Pharma Corporation, P.O. Box Suwon 61, Republic of KoreaReceived July 9, 1996(3R,4R)-4-Acetoxy-3-[(1'R-tert-butyldimethylsilyloxy)ethyl]-2-azetidinone,one of the best synthons for car-bapenems and penems was efficiently synthesized from readily available L -threonine via double azetidinonering formation.IntroductionSince the isolation of (+)-thienamycin by a Merckresearch group