二碳酸二叔丁酯

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

2-甲基-2-丙基(1R,4S)-3-氧代-2-氮杂双环[2.2.1]庚-5-烯-2-羧酸酯

(-)-文斯内酯

cis-4-(benzoyloxy)-2-cyclopentenyl benzoate