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Bioactive dibenzocyclooctadiene lignans from the stems of Schisandra neglecta
Xue-Mei Gao1, Rui-Rui Wang, De-Yun Niu
1State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, People's Republic of China.
Abstract:
Seven new unusual dibenzocyclooctadiene lignans, neglignans A-G (1-7), together with 16 known dibenzocyclooctadiene lignans, were isolated from the stems of Schisandra neglecta. Compounds 1 and 2 are the first dibenzocyclooctadiene lignans bearing a carboxyl group at C-4, and compounds 3 and 4 are the first 7,8-seco-dibenzocyclooctadiene lignans found from Nature. The new compounds (1-7) and several of the known compounds were evaluated for their anti-HIV activity and cytotoxicity. Compounds 2 and 6 showed anti-HIV-1 activities with therapeutic index values greater than 50, and compound 4 showed cytotoxicity against the NB4 and SHSY5Y cancer cell lines with IC50 values of 2.9 and 3.3 μM, respectively.
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