Chromone glycosides and hepatoprotective constituents of Hypericum erectum.

Two chromone glycosides, hyperimone A [7-(beta-D-glucopyranosyloxy)-5-hydroxy-2-(1-methylethyl)-4H-1-benzopyran-4-one (1)] and hyperimone B [7-(beta-D-glucopyranosyloxy)-5-hydroxy-3-methyl-4H-1-benzopyran-4-one (2)], together with six known compounds were isolated from the methanolic extract of the whole plant of Hypericum erectum. 1,3,5,6-Tetrahydroxyxanthone (5) and I3, II8-biapigenin (6) showed moderate hepatoprotective activity with EC(50) values of 160.2 +/- 0.6 microM and 217.7 +/- 1.3 microM, respectively, against tacrine-induced cytotoxicity in HepG2 cells.