Geng Chang-An, Zhang Xue-Mei, Shen Yong, Zuo Ai-Xue, Liu Ji-Feng, Ma Yun-Bao, Luo Jie, Zhou Jun, Jiang Zhi-yong, Chen Ji-Jun
State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, PRC.
Org Lett. 2009 Nov 5;11(21):4838-41. doi: 10.1021/ol901881w.
Swerilactones C (1) and D (2), two novel diastereomeric lactones with an unprecedented 6/6/6/6/6 pentacyclic ring system, were isolated from the traditional Chinese herb Swertia mileensis. Their structures and relative stereochemistry were elucidated on the basis of spectroscopic methods and further confirmed by X-ray single-crystal diffraction analysis. In vitro antihepatitis B virus (HBV) assay on the Hep G 2.2.15 cell line showed that both compounds 1 and 2 exhibited inhibitory activities against the secretion of HBsAg (IC(50) = 1.24 and 2.96 mM, respectively) and HBeAg (IC(50) = 0.77 and 1.47 mM, respectively).
