During the process exploring anti-viral compounds from Phyllanthus species, eight new highly oxygenated bisabolane sesquiterpenoid glycoside phyllaemblicins G1-G8 (1-8) were isolated from Phyllanthus emblica, along with three known compounds, phyllaemblicin F (9), phyllaemblic acid (10) and glochicoccin D (11). Phyllaemblicin G2 (2), bearing a tricyclo [184.108.40.206] oxygen bridge ring system, is an unusual sesquiterpenoid glycoside, while phyllaemblicins G6-G8 (6-8) are dimeric sesquiterpenoid glycosides with two norbisabolane units connecting through a disaccharide. All the structures were elucidated by the extensive analysis of HRMS and NMR data. The relative configuration of phyllaemblicin G2 was constructed based on heteronuclear coupling constants measurement, and the absolute configurations for all new compounds were established by calculated electronic circular dichroism (ECD) using time dependent density functional theory. The sesquiterpenoid glycoside dimers 6-9 displayed potential anti-hepatitis B virus (HBV) activities, especially for the new compound 6 with IC50 of 8.53 +/- 0.97 and 5.68 +/- 1.75 mu M towards the HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively.
1.Chinese Acad Sci, Kunming Inst Bot, State Key Lab Phytochem & Plant Resources West Ch, Kunming 650201, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Zhengzhou Univ, Sch Pharmaceut Sci, Zhengzhou 450001, Peoples R China 4.Zhengzhou Univ, Acad Med & Pharmaceut Sci, Henan Key Lab Pharmacol Liver Dis, Zhengzhou 450052, Peoples R China
Lv,Jun-Jiang;Wang,Ya-Feng;Zhang,Jing-Min;Yu,Shan;Wang,Dong;Zhu,Hong-Tao;Cheng,Rong-Rong;Yang,Chong-Ren;Xu,Min;Zhang,Ying-Jun.Anti-hepatitis B virus activities and absolute configurations of sesquiterpenoid glycosides from Phyllanthus emblica,ORGANIC & BIOMOLECULAR CHEMISTRY,2014,55(48):6530-6533