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Published on: September 28, 2022
Alkaloids with Immunosuppressive Activity from the Bark of Pausinystalia yohimbe
Ye Liu1,2, Heng-Yi Yu1,3, Hong-Zhe Xu1
1Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College , Huazhong University of Science and Technology , Wuhan 430030 , People's Republic of China.
Abstract:
Ten new alkaloids (1-10), including two pairs of enantiomeric mixtures (5a,b and 6a,b), and 15 known analogues (11-25) were obtained from the bark of Pausinystalia yohimbe. The structures of 1-25 were established by spectroscopic methods, and the absolute configurations of compounds 1-10 were resolved by X-ray diffraction and ECD data analyses. The in vitro immunosuppressive activities of selected isolates were tested. Compounds 11 and 16 exhibited moderate inhibition with IC50 values of 16.8 and 27.6 μM against ConA-induced T lymphocyte proliferation and 13.5 and 40.5 μM against LPS-induced B lymphocyte proliferation, respectively.
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