t-Butyl 2-[(3R,4R)-3-phenoxyacetamido-4-[(RS)-tetrahydrothien-2-yl carbonylmethylthio]azetidin-2-on-1-yl]-2-tri-n-butylphosphoranylideneacetate 在
silica gel 、
ethyl acetate n-hexane 作用下,
以
甲苯 为溶剂,
反应 24.0h,
以Re-chromatography of this material afford the low Rf diastereoisomer of the title compound (0.428 g, 21%)的产率得到t-Butyl (6R,7R)-7-phenoxyacetamido-3-(tetrahydrothien-2-yl)ceph-3-em-4-carboxylate