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

Three new secoiridoid aglycones of (-)-swermusic acid A (1) and B (3), and (-)-swerimuslatone A (2), and four new secoiridoid glycosides of 6'-O-formylsweroside (4),6'-O-formylgentiopicroside (5), 6'-O-acetylamarogentin (6) and 6'-O-acetylamaronitidin (7), along with 40 known compounds (8-47) were isolated from Swertia mussotii. Their structures were elucidated on the basis of extensive spectroscopic analyses including MS, IR, UV, 1D- and 2D-NMR. Forty-five compounds from S. mussotii were evaluated for their anti-HBV activity on the HepG 2.2.15 cell line in vitro inhibiting the secretions of HBsAg and HBeAg, as well as HBV DNA replication. Six of the nine phenols 26-29,31 and 32 exhibited activities inhibiting HBsAg and HBeAg secretion with IC50 values from 0.23 to 5.18 mM, and HBV DNA replication with IC50 values from <0.06 to 2.62 mM. Moreover, isooriention (45) displayed significant anti-HBV activities against secretions of HBsAg and HBeAg with IC50 value of 0.79 and 1.12 mM, as well as HBV DNA replication with IC50 value of 0.02 mM. (C) 2015 Elsevier B.V. All rights reserved.