ethyl 7-methoxy-2-oxochromene-3-carboxylate

diethyl 2-[(1,3-thiazol-2-ylamino)methylidene]propanedioate

ethyl 3-methyl-5-oxo-[1,3]thiazolo[3,2-a]pyrimidine-6-carboxylate

脲甲烯丙二醇二乙酯

diethyl 2-(morpholin-4-ylmethylidene)propanedioate