(S)-6-ethyl-2,2-spirocyclobutyl-3,4-2H-dihydrochromen-4-amine 、
[(S)-2-(3-allyl-phenyl)-1-(S)-oxiranyl-ethyl]-carbamic acid tert-butyl ester 以
乙醇 为溶剂,
以46%的产率得到tert-butyl N-[(2S,3R)-4-[[(4S)-6-ethylspiro[3,4-dihydrochromene-2,1'-cyclobutane]-4-yl]amino]-3-hydroxy-1-(3-prop-2-enylphenyl)butan-2-yl]carbamate