Anti-hepatitis B virus active lactones from the traditional Chinese herb:Swertia mileensis - Geng, C A; Wang, L J; Zhang, X M; Ma, Y B; Huang, X Y; Luo, J; Guo, R H; Zhou, J; Shen, Y; Zuo, A X; Jiang, Z Y; Chen, J J (Chem Eur J, 2011)