Indonesian medicinal plants. XXV. Cancer cell invasion inhibitory effects of chemical constituents in the parasitic plant Scurrula atropurpurea (Loranthaceae)

Six fatty acids (1-6), two xanthines (7, 8), two flavonol glycosides (9, 10), one monoterpene glucoside (11), one lignan glycoside (12), and four flavanes (13-16) were clarified by a bioassay-guided separation as chemical constituents of Scurrula atropurpurea (Loranthaceae), a parasitic plant of the tea plant Thea sinensis (Theaceae). Among these constituents, it was found that the alkynic fatty acid octadeca-8,10,12-triynoic acid (6) exhibits a more potent inhibitory effect on cancer cell invasion in vitro than flavanes [(+)-catechin (13), (-)-epicatechin (14), (-)-epicatechin-3-O-gallate (15) and (-)-epigallocatechin-3-O-gallate (16)].