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Diterpenoids with Rearranged 9(10→11)-abeo-10,12-Cyclojatrophane Skeleton and the First (15S)-Jatrophane from
Zhi-Nan Xiang1, Qi-Lin Tong1, Jun-Cheng Su2
1Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, Pharmacy Department of Tongji Medical School, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China.
Abstract:
Two novel diterpenoids, one with a rearranged trans,trans-fused tricyclo[10.3.0.04,6]pentadecane framework (1) and the other with an unprecedented 15S configuration (2), were isolated from Euphorbia helioscopia. Their structures were elucidated by extensive analysis of HR-ESI-MS, NMR, quantum-chemical calculation, and X-ray crystallographic data. Biosynthetically, 1 has a unique "cyclopropane-shift-like" biogenesis involving an oxa-di-π-methane (ODPM) rearrangement, which inspired us to accomplish the biomimetic conversion of 3 to 1. Moreover, compound 1 displayed a potent immunosuppressive effect by inhibiting Kv1.3 voltage-gated channels.
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