(3S,4R)-3-[(R)-1-hydroxyethyl]-4-[(R)-1-methyl-3-diazo-3-allyloxycarbonyl-2-oxopropyl]-2-azetidinone 、
(2R,4S)-1-allyloxycarbonyl-4-acetylthio-2-[2-(5-hydroxymethyl-imidazol-1-yl)ethyl]pyrrolidine 以to give allyl (4R,5S,6S)-3-[(2R,4S)-1-allyloxycarbonyl-2-{2-(5-hydroxymethylimidazol-1-yl)ethyl}pyrrolidin-4-yl]thio-6-[(1R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (802 mg) as a yellow solid的产率得到allyl (4R,5S,6S)-3-[(2R,4S)-1-allyloxycarbonyl-2-{2-(5-hydroxymethylimidazol-1-yl)ethyl}pyrrolidin-4-yl]thio-6-[(1R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate