2-乙基-3-(2-乙氧基-2-氧代乙基)-5-甲基-1H-吡咯-2,4-二羧酸-4-苄酯

diethyl 2,4-dihydroxy-6-methylbenzene-1,3-dicarboxylate

diethyl 1,2,6-trimethyl-4-oxopiperidine-3,5-dicarboxylate

ethyl 3-(2-ethoxy-2-oxoethyl)-5-methyl-1H-pyrrole-2-carboxylate

ethyl 3-(4-methoxyanilino)-3-oxopropanoate