New Lignans from roots of Kadsura coccinea.

Four new dibenzocyclooctadiene lignans, named heilaohusus A-D (1-4), one new arylnaphthalene lignan named heilaohusu E (5), and seven known analogues (6-12) were isolated from the roots of Kadsura coccinea. Their structures and configurations were elucidated by a combination of HR-ESI-MS, ¹H NMR, ¹³C NMR, HSQC, HMBC, NOESY and CD spectra. Among the known compounds, compounds 6 and 8-12 were isolated from this plant for the first time. All of compounds were evaluated for their cytotoxicity activities, compounds 3, 6 and 7 showed weak cytotoxicity against four human cancer cell lines (HepG-2, HCT-116, BGC-823 and Hela) with IC₅₀ values range from 13.04 to 21.93 μM. Compounds 1 and 7 demonstrated potential anti-RA (rheumatoid arthritis) activity against RA-FLS cell line with IC₅₀ values of 14.57 and 11.70 μM, respectively.