甲基溴化镁 、
(6R)-7t-acetylamino-3-methyl-4-methylene-5t,8-dioxo-(6rH)-5λ4-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 2,2,2-trichloro-ethyl ester 以
四氢呋喃 为溶剂,
以21%的产率得到(5S,6R,7R)-7-Acetylamino-4-ethyl-3-methyl-5,8-dioxo-5λ
4-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 2,2,2-trichloro-ethyl ester