Four new eremophilanoid sesquiterpenes from Senecio oldhamianus

Four new eremophilanoid sesquiterpenes were isolated from Senecio oldhamian us. On the basis of spectroscopic and X-ray diffraction analysis, their str uctures were elucidated as: 7 beta ,11-epoxy-9 alpha, 10 alpha -epoxy-8-oxo eremophilane (1), 8, 11-dioxol-6-en-9 alpha, 10 alpha -epoxy-8 beta -hydrox yeremophilane (2), 7(11)-en-9 alpha, 10 alpha -epoxy-8-oxoeremophilane (3), 6-en-9 alpha, 10 alpha -epoxy-11-hydroxy-8oxoeremophilane (4). The experim ent of anticancer activity reveals that compound 1 promoted, while compound 2 and 3 inhibited, the growth of human hepatoma cells (SMMC - 7721) and hu man ovarioneus cells (HO-8910).