(3aR,5R,6R,6aR)-6-bromo-2-oxo-hexahydrocyclopentaoxazole-5-carboxylic acid methyl ester

(3S,4R)-4-tert-butoxycarbonylamino-3-hydroxycyclopent-1-enecarboxylic acid

(-)-methyl (1S,4R)-4-amino-cyclopent-2-ene-1-carboxylate hydrochloride

(1S,2S,4R,5R)-methyl 4-((tert-butoxycarbonyl)amino)-6-oxabicyclo[3.1.0]hexane-2-carboxylate