Two New Xanthone Glycosides from Ventilago Leiocarpa Benth

Abstract

Two new xanthone glycosides, 8-hydroxy-3-methyl-6-methoxyxanthone-1- O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranose (1) and 8-hydroxy-3-methyl-6-methoxyxanthone-1- O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranose (2), together with two known anthraquinones, 1,8-dihydroxy-3-methylanthraquinone (3) and 1,3,8-trihydroxy-6-methylanthraquinone (4), were isolated from the bark of Ventilago leiocarpa Benth. The structures were determined by various NMR spectroscopic and MS analyses. Compounds 1–4 were tested for their inhibitory activities against T and B cell proliferation, and 2 exhibited moderate inhibitory activities against LPS-induced B cell proliferation and ConA-induced T cell proliferation, with IC50 values of 8.8 and 17.9 μM, respectively.