title: 5-Hy-droxy-3,4',6,7-tetra-meth-oxy-flavone.
abstract: The title compound, C(19)H(18)O(7) [systematic name 5-hy-droxy-3,6,7-tri-meth--oxy-2-(4-meth-oxy-phen-yl)-4H-1-benzopyran-4-one], is a flavonoid which was isolated from the traditional Chinese medicine Laggera alata. The benzene ring of the benzopyran-one unit forms dihedral angles of 1.72 (3) and 37.39 (5)° with the pyran ring and the substituent benzene ring, respectively. The mol-ecular conformation is stabilized by an intra-molecular phenol O-H⋯O(ketone) hydrogen bond.
authors: Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research, Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632,  People's Republic of China.
authors: Hua-Wei
authors: HW
authors: Geng
authors: Guo-Cai
authors: GC
authors: Wang
authors: Guo-Qiang
authors: GQ
authors: Li
authors: Ren-Wang
authors: RW
authors: Jiang
authors: Yao-Lan
authors: YL
authors: Li