Two New Xanthone Glycosides from Polygala tenuifolia

Two new xanthone glycosides,polygalaxanthone Ⅳ and Ⅴ were isolated from the roots of Polygala tenuifolia Willd.Their structures were established as 6-O-[(α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl]-1-hydroxy-3,7-dimethoxyxanthone (polygalaxanthone IV),and 6-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl]-1,3-dihydroxy-7-methoxyxanthone (polyga-laxanthone Ⅴ),respectively,on the basis of chemical and spectral evidence.