5-亚甲基螺[2.4]庚烷

diethyl (1S,2R)-4-methylidenecyclopentane-1,2-dicarboxylate

反式-4-亚甲基-1,2-环戊烷二羧酸二乙酯

triethyl 4-oxopyrrolidine-1,2,3-tricarboxylate

1,2-二甲基丙基乙酸酯