diethyl 2-bromo-2-(2-bromoethoxymethyl)propanedioate

diethyl 2-[amino(phenyl)methylidene]propanedioate

3-溴-7-羟基吡唑并[1,5-a]嘧啶-6-羧酸乙酯

ethyl 5-oxo-2-phenyl-1,2-oxazole-4-carboxylate

diethyl 2-cyanopropanedioate