Chemical Constituents of Inula japonica

Objective: To study the chemical constituents of Inula japonica. Methods: Silica gel, Sephadex LH-20,MCI and semipreparative HPLC were used to isolate and purify the constituents of Inula japonica,and the chemical structures were elucidated by chemical properties, MS and NMR analysis. Results: 14 compounds were isolated and their structures were identified as ivangustin( 1),1-acetoxy-6α-hydroxyeriolanolide( 2), 1β-hydroxyalantolactone( 3),tomentosin( 4),11,13-dihydroinuchinenolide B( 5), britanlin A( 6),vomifoliol( 7), 17-hydroxy-16α-ent-kauran-19-oic acid( 8), 12-hydroxygeranylgeraniol ( 9), dihydroquercetin( 10), kaempferol( 11), quercetin( 12), dihydroconiferyl alcohol( 13) and fareanol( 14). Conclusion: Compounds 5,6,9,13 and 14 are isolated from this plant for the first time.