ethyl (2R)-2-[(S)-acetyloxy-[(2R,3R,4R)-3,4,5-triacetyloxyoxolan-2-yl]methyl]-1,4-dimethyl-3-oxo-2,7-dihydro-1,4-diazepine-5-carboxylate 以33%的产率得到Trifluoro-acetate(1R,2R,8R,9S,10R,11R,12R)-9,11,12-triacetoxy-5-ethoxycarbonyl-2,6-dimethyl-7-oxo-13-oxa-6-aza-2-azonia-tricyclo[8.2.1.0
2,8]tridec-4-ene;