Institution: | 1. Biology Department, College of Life Science, Shanghai Normal University, 100 Guilin Road, Shanghai, 200234 China
State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203 China;2. Shandong Laboratory of Yantai Drug Discovery, Bohai rim Advanced Research Institute for Drug Discovery, Yantai, 264117 China;3. Key Laboratory of Zhanjiang for Research and Development Marine Microbial Resources in the Beibu Gulf Rim, Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023 China;4. Biology Department, College of Life Science, Shanghai Normal University, 100 Guilin Road, Shanghai, 200234 China;5. State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203 China;6. College of Materials Science and Engineering, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha, 410004 China |
Abstract: | Two new highly functionalized cembrane diterpenoids named ximaolobophytolides A ( 1 ) and B ( 2 ) as minor components, together with seven related known compounds ( 3 – 9 ), have been isolated and identified from the Ximao soft coral Lobophytum sp. They were characterized by the presence of an α-methylene-γ-lactone moiety. Based on the comprehensive analyses of 1D and 2D NMR spectroscopic data, the absolute configurations of these two new compounds were elucidated by the combination of quantum mechanical (QM)-NMR and time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculation approaches. In the anti-tumor bioassays, compounds 3 – 9 showed moderate to significant inhibitory effects (IC50 values ranging from 29.66 to 0.39 μM) against the proliferations of five tumor cells HEL, A549, H1975, MDA-MB-231, and H1299. It might be worthy to point out that compounds 4 , 7 , and 8 exhibited better anti-tumor activities than that of the positive control Doxorubicin. |