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Dibenzocyclooctadiene Lignans from Kadsura polysperma and Their Antineurodegenerative Activities

State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, People's Republic of China.
Journal of Natural Products (Impact Factor: 3.95). 02/2012; 75(2):249-56. DOI: 10.1021/np200937h
Source: PubMed

ABSTRACT Eleven new dibenzocyclooctadiene lignans, polysperlignans A-K (1-11), and eight known analogues (12-19) were isolated from the stems of Kadsura polysperma. Their structures and absolute configurations were established using a combination of MS, NMR, CD, and single-crystal X-ray diffraction techniques. Selected compounds were evaluated for activity against β-amyloid- or hydrogen peroxide-induced neurotoxicity on PC12 cells, and 1, 2, 4, 5, 13, and 16 showed statistically significant neuroprotective effects in these in vitro assays.

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