{(2R,3R)-3-(1-Fluoro-ethyl)-2-[(E)-6-(4-nitro-benzyloxycarbonylamino)-2-oxo-hex-3-enyl]-4-oxo-azetidin-1-yl}-(triphenyl-λ5-phosphanylidene)-acetic acid 4-nitro-benzyl ester 以
甲苯 为溶剂,
以55%的产率得到(5R,6R)-6-(1-Fluoro-ethyl)-3-[(E)-4-(4-nitro-benzyloxycarbonylamino)-but-1-enyl]-7-oxo-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester