Chemical constituents of Swertia yunnanensis and their anti-hepatitis B virus activity.

Abstract: Four new triterpenoids, sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4), along with nineteen known compounds (5–23) were isolated from Swertia yunnanensis. Based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR, [α]D), the structures of sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4) were elucidated as taraxer-14-ene-3α,6β-diol, oleanolic acid 28-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranoside, 2α,3β-di-hydroxyolean-12-en-28-oic acid 28-O-β-d-glucopyranosyl(1→6)-β-d-glucopyranosyl (1→6)-β-d-glucopyranosyl(1→2)-β-d-glucopyranoside and hederagenin 28-O-β-d-glucopyranosyl(1→6)-β-d-glucopyranosyl(1→6)-β-d-glucopyranosyl(1→2)-β-d-glucopyranoside, respectively. Twenty-two compounds were evaluated for their anti-HBV activities on the HepG 2.2.15 cell line in vitro, of which nine compounds showed potent anti-HBV activities. Compounds 1, 5–6, 14–16 and 19 showed activities against the secretion of HBsAg (IC50 values from 0.10 to 1.76mM) and HBeAg (IC50 values from 0.04 to 1.41mM), and compounds 11 and 13–16 exhibited significant inhibition on HBV DNA replication (IC50 values from 0.01 to 0.09mM). [Copyright &y& Elsevier]