(1R,2S,5S)-3-[(2S)-2-amino-3,3-dimethyl-butanoyl]-N-[(1S)-1-cyano-2-[(6R)-5-oxo-4-azaspiro[2.4]heptan-6-yl]ethyl]-6,6-dimethyl-3-azabicyclo[3.1.0]hexane-2-carboxamide 、
2,2-difluoro-1-(fluoromethyl)cyclopropanecarboxylic acid 在
N-甲基咪唑 、 N,N,N',N'-tetramethylchloroformamidinium hexafluorophosphate 作用下,
以
乙腈 为溶剂,
生成 (1R,2S,5S)-N-((S)-1-cyano-2-((R)-5-oxo-4-azaspiro[2.4]heptan-6-yl)ethyl)-3-((2S)-2-(2,2-difluoro-1-(fluoromethyl)cyclopropanecarboxamido)-3,3-dimethylbutanoyl)-6,6-dimethyl-3-azabicyclo[3.1.0]hexane-2-carboxamide