1,2,6,8-Tetrahydroxy-9H-xanthen-9-one 1,3,7,8-Tetrahydroxyxanthone 22172-15-2 5-18-05-00185 (Beilstein Handbook Reference) 9H-Xanthen-9-one, 1,2,6,8-tetrahydroxy- (9CI) BRN 0270047 Norswertianin Xanthen-9-one, 1,2,6,8-tetrahydroxy-