Abstract
Nine highly oxygenated flavonoids, having eight oxygen functional groups at C-3, 3', 4', 5, 5', 6, 7 and 8, were isolated from Polygonum orientale. Of these compounds, seven (1, 2, 3a, 4, 5a, 6 and 7a) are new compounds and the structures were determined on the basis of spectral evidence as 3, 3', 5, 6, 7, 8-hexamethoxy-4', 5'-methylenedioxy-(1), 5-hydroxy-3, 3', 6, 7, 8-pentamethoxy-4', 5'-methylenedioxy-(2a), 3'-hydroxy-3, 4', 5, 5', 6, 7, 8-heptamethoxy-(3a), 3, 3', 5, 8-tetramethoxy-4', 5', 6, 7-bis (methylenedioxy)-(4), 3'-hydroxy-3, 4', 5, 5', 8-pentamethoxy-6, 7-methylenedioxy-(5a), 3, 3', 4', 5, 5', 8-hexamethoxy-6, 7-methylenedioxy-(6) and 3', 5-dihydroxy-3, 4', 5', 8-tetramethoxy-6, 7-methylenedioxyflavone (7a).
