3,3'-(2-Methoxyethylidene)bis(4-hydroxycoumarin)

2-hydroxy-3-[1-(2-hydroxy-4-keto-chromen-3-yl)-2-methoxy-ethyl]chromone

2-hydroxy-3-[1-(2-hydroxy-4-oxochromen-3-yl)-2-methoxyethyl]chromen-4-one

2-hydroxy-3-[1-(2-hydroxy-4-oxo-chromen-3-yl)-2-methoxy-ethyl]chromen-4-one