diethyl thiophene-3,4-dicarboxylate

4,5-dibromocyclopent-4-ene-1,3-dione

3-[N-(苯基)氨基]-3-氧代丙酸乙酯

2-硫氰酸基乙酸乙酯

ethyl 9-(5-oxocyclopenten-1-yl)nonanoate