7-羟基-4-氧代-4H-苯并吡喃-2-羧酸乙酯

ethyl 8-cyano-7-hydroxy-4-oxochromene-2-carboxylate

ethyl 4-oxo-7-phenylmethoxychromene-2-carboxylate

4-(4-benzyloxy-2-hydroxy-phenyl)-2,4-dioxo-butyric acid ethyl ester

4-苄氧基-2-羟基苯乙酮