5-acetyl-2-sulfanylidene-1H-pyrimidin-4-one

5-acetyl-3-methyl-2H-[1,2]thiazolo[5,4-b]pyridin-4-one

ethyl 2-acetyl-5-ethoxypent-4-enoate

ethyl 2-(hydroxymethylidene)-3-oxobutanoate

乙基7-甲基吡唑并[1,5-a]嘧啶-6-羧酸酯