(2S,2aS,2bR,4R,5aR,6S)-4-Acetoxy-5a-benzenesulfonyl-2-[(R)-1-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2b-methyl-1-oxo-octahydro-3-oxa-6a-aza-cyclobuta[a]pentalene-6-carboxylic acid benzyl ester 在
1,8-二氮杂双环[5.4.0]十一碳-7-烯 作用下,
以
四氯化碳 为溶剂,
反应 6.0h,
以70%的产率得到benzyl (1S,2S,3S,9R)-9-acetyloxy-3-[(1R)-1-[tert-butyl(dimethyl)silyl]oxyethyl]-1-methyl-4-oxo-10-oxa-5-azatricyclo[5.3.0.02,5]dec-6-ene-6-carboxylate