(1R,2S,6R,7S,8R,9S)-9-Hydroxy-8-methoxy-3,4-diaza-tricyclo[5.2.2.02,6]undec-3-ene-2,6-dicarboxylic acid dimethyl ester 、
乙酰氯 以80%的产率得到(1S,2R,6R,7R,8S,9R)-9-Acetoxy-3-acetyl-8-methoxy-3,4-diaza-tricyclo[5.2.2.0
2,6]undec-4-ene-2,6-dicarboxylic acid dimethyl ester