(3aS,5S,6S,6aS)-6-bromo-2-oxo-hexahydrocyclopentaoxazole-5-carboxylic acid methyl ester

(1R,4S)-(+)-4-氨基环戊-2-烯甲酸

2-氮杂双环[2.2.1]庚-5-烯-3-酮

(1S,4R,6S)-6-acetoxy-2-(tert-butoxycarbonyl)-2-azabicyclo[2.2.1]heptan-3-one

(1S,2R,4R)-N-Boc-1-氨基-2-羟基环戊烷-4-羧酸甲酯