2,3,5,6-四甲基-1H,7H-吡唑并[1,2-a]吡唑-1,7-二酮

甲基4-甲基-5-氧代-4,5-二氢-1H-吡唑-3-羧酸酯

ethyl 4-chloro-3-methylquinoline-2-carboxylate

ethyl 5-methyl-4-oxo-2-(tribromomethyl)-1H-pyrimidine-6-carboxylate

ethyl 6-amino-2,5-dimethylpyrimidine-4-carboxylate