[(2R,3S)-3-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-2-(4-carbamoyl-phenoxythiocarbonylsulfanyl)-4-oxo-azetidin-1-yl]-oxo-acetic acid 4-nitro-benzyl ester 在
P-甲基-亚膦酸二甲酯 作用下,
以
氯仿 为溶剂,
以83%的产率得到(5R,6S)-6-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-3-(4-carbamoyl-phenoxy)-7-oxo-4-thia-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester