5-Hydroxy-3,4′,6,7-tetramethoxyflavone

Abstract

The title compound, C19H18O7 [systematic name 5-hydroxy-3,6,7-trimethoxy-2-(4-methoxyphenyl)-4H-1-benzopyran-4-one], is a flavonoid which was isolated from the traditional Chinese medicine Laggera alata. The benzene ring of the benzopyranone unit forms dihedral angles of 1.72 (3) and 37.39 (5)° with the pyran ring and the substituent benzene ring, respectively. The molecular conformation is stabilized by an intramolecular phenol O—H...Oketone hydrogen bond.