(2S,4R)-4-(2-chloro-benzenesulfonyl)-pyrrolidine-2-carboxylic acid cyanomethyl-amide hydrochloride 、
3-氧杂环丁酮 以to give (2S,4R)-4-(2-chloro-benzenesulfonyl)-1-oxetan-3-yl-pyrrolidine-2-carboxylic acid cyanomethyl-amide as a colorless foam的产率得到(2S,4R)-4-(2-chloro-benzenesulfonyl)-1-oxetan-3-yl-pyrrolidine-2-carboxylic acid cyanomethyl-amide