Seven New Secoiridoids with Anti-Hepatitis B Virus Activity fromSwertia angustifolia

Seven new secoiridoids, swertianglide (1) and swertianosides A−F (2–7), together with fifteen known compounds, were isolated from the whole plants of Swertia angustifolia. Their structures were elucidated on the basis of extensive spectroscopic analyses ([α]D, UV, IR, MS, 1D- and 2D-NMR). Fourteen compounds were evaluated for their anti-hepatitis B virus (HBV) activities on the Hep G 2.2.15 cell line in vitro. Compound 2, an unusual secoiridoid glycoside dimer, showed significant activities inhibiting the secretion of HBsAg (IC50 0.18 mM, SI 3.11) and HBeAg (IC50 0.12 mM, SI 4.67).