ABSTRACT
Objective: To study the chemical constituents from Rhynchosia volubilis. Methods: The compounds were isolated and purified by a combination of various chromatographic techniques including silica gel, ODS, Toyopearl HW-40C, Sephadex LH-20, and semi-preparative HPLC chromatography. Their structures were identified by physicochemical properties and spectroscopic data. Results: Thirteen compounds were isolated from the petroleum ether extracts of R. volubilis and their structures were elucidated as (-)-sigmoidin E (1), lupinifolin (2), precatorin B (3), cajanone (4), sophoraisoflavanone B (5), 5,3’-dihydroxy-4’-methoxy-5’- γ,γ-dimethylallyl-2″,2″-dimethylpyrano [5,6:6,7] isoflavanone (6), genistein (7), licoisoflavone A (8), erylatissin B (9), neo-bavaisoflavone (10), lupeol (11), betulinic aldehyde (12), and clionasterol (13). Compounds 1-10 were all prenylated flavonoids, of which compounds 1-2 were dihydroflavones, compounds 3-6 were dihydroisoflavones, and compounds 7-10 were isoflavones. Compounds 11-12 were lupine triterpenoids, and compounds 13 was a sterol. Conclusion: Compounds 1, 5-6, 8-10, 12 and 13 are isolated from the genus for the first time, while compounds 1-3 and 5-13 are separated from this plant for the first time.