Abstract: | The root of Rhus semialata (Anacardiaceae) was a folk herb for treating diarrhea, spermatorrhea and malaria.1,2]Recently, it was found to have other activity of inhibitors of Iκ Bα kinase.3] inhibited human cell proliferation activated by IL-1β and IL-6, antifungal activity and antithrombin activity. The roots of it, collected from the island of Taiwan, was extracted with MeOH. The n-BuOH-soluble materials of the extract were subjected to Sephadex LH-20 (H2O/MeOH)column chromatography and then separated by RP-18 and Silica gel to yield rhusouyangins A (1), B (2), and C (3) as colorless amorphous solids, together with 2,3-cis-3,4-trans-4',7-dihydroxyflavan-3,4-diol, 2,3-trans-3,4-cis-4',7-dihydroxyflavan-3,4-diol, 3',5,5',7-tetrahydroxyflavanone. |