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Published on: September 28, 2022
New adenine analogues and a pyrrole alkaloid from Selaginella delicatula
Cai-Ping Yao1,2, Zhen-Xing Zou1,2, Yan Zhang2
1a National Institution of Drug Clinical Trial , Xiangya Hospital of Central South University , Changsha , PR China.
Abstract:
Phytochemical study on the n-BuOH extract of Selaginella delicatula lead to the isolation, characterization and structure elucidation of two new adenine analogues, delicatulines A (1) and B (2), one new pyrrole alkaloid (4), and five known compounds (3, 5-8). These new substances all contain an aliphatic chain in their parent nucleus, which were unusual to find in plants. In the present study, they were identified from Selaginellaceae for the first time. The structures and absolute configurations of these new compounds were determined by a combination of NMR and CD spectroscopic analyses. Compounds 1, 3 and 4 were evaluated for their inhibitory activities on HBV surface antigen and HBV DNA in HepAD38 cells. The results showed that these compounds had only weak or no inhibitive effects on HBV.
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