A new acetylated spirostanol saponin and other constituents from the rhizomes of Dioscorea althaeoides R. Knuth (Dioscoreaceae)

Abstract

A new acetylated spirostanol saponin (7), dioscin-6′-O-acetate, was isolated from the rhizomes of Dioscorea althaeoides R. Knuth (Dioscoreaceae), together with fourteen known compounds, including three spirostanol saponins (1–2, 6), three furostanol saponins (10–12), one diarylheptanoid (3), three sterols (4–5, 9), three aliphatic acids (8, 13–14) and one aliphatic alkane (15). Their structures were established by extensive 1D- and 2D- NMR (DEPT, 1H–1H COSY, HSQC, HMBC and NOESY) experiments in conjunction with IR and HRESI/TOF-MS data, as well as the results of acid hydrolysis. The compounds (3–8, 10–15) were isolated from this species for the first time. The chemotaxonomic significance of these compounds was also discussed