4H-1-Benzopyran-4-one, 5,6,7,8-tetramethoxy-2-(3,4,5-trimethoxyphenyl)- 5,6,7,8-Tetramethoxy-2-(3,4,5-trimethoxyphenyl)-4H-1-benzopyran-4-one 6965-36-2 NSC 67580