tert-butyl 2-acetylpyrrole-1-carboxylate

tert-butyl 2-oxocyclopentane-1-carboxylate

2-甲基-2-丙基4-硝基-11-氮杂三环[6.2.1.02,7]十一碳-2,4,6-三烯-11-羧酸酯

7-O-tert-butyl 2-O-ethyl 3-bromo-7-azabicyclo[2.2.1]hepta-2,5-diene-2,7-dicarboxylate