乙醇

ethyl 4-(2-hydroxyphenyl)-2,4-dioxobutanoate

7-羟基-4-氧代-4H-苯并吡喃-2-羧酸乙酯

ethyl 2-hydroxy-4-oxochroman-2-carboxylate

2'-乙酰氧基苯乙酮