ethyl 2-(4-oxo-[1,2,4]triazino[3,4-a]phthalazin-3-yl)acetate

diethyl 2-(1-phthalazinylhydrazono)succinate

2-(4-氯苯基)-6-氧代-1,6-二氢-4-嘧啶羧酸

1-甲基-5-氧代-4H-吡唑-3-羧酸乙酯

2-氟-3-氧-丁酸-1,4-二乙酯