Synthetic Studies on Penems and Carbapenems (). Compounds Derived by Cleavage of the -Lactam Ring during (Alkylthio) thiocarbonylation of a 4-Mercapto-3-phenylacetamidoazetidin-2-one Derivative

摘要

When (3R,4R)-1-(1-benzyloxycarbonyl-2-methyl-1-propenyl)-4-mercapto-3-phenylacetamidoazetidin-2-one(8) was reacted with carbon disulfide and alkyl halides in the presence of triethylamine, the ￥a-lactam ring was cleaved to give (Z)-and (E)-1-alkylthio-5-benzyloxycarbonyl-6-methyl-2-phenylacetamido-4-aza-1,5-heptadien-3-one (13-16) or 2-benzyl-4-(3-benzyloxycarbonyl-4-methyl-1-oxo-2-aza-3-pentenyl)thiazole(17).