1,8-Dihydroxy-2,3,4,6-tetramethoxy-9H-xanthen-9-one 1,8-Dihydroxy-3,5,6,7-tetramethoxyxanthone 82868-96-0 9H-Xanthen-9-one, 1,8-dihydroxy-2,3,4,6-tetramethoxy- Demethyleustomin