Heilaohuguosus A-S from the fruits of Kadsura coccinea and their hepatoprotective activity.

Phytochemical investigations on the fresh fruits of Kadsura coccinea (Lem.) A. C. Sm. have led to the isolation of fourteen undescribed 2,2'-cyclolignans named heilaohuguosus A-N, four undescribed aryltetrahydronaphthalene lignans, heilaohuguosus O-R and one tetrahydrofuran lignan, heilaohuguosu S, with twenty-seven previously described lignan analogues. Their structures and absolute configurations of heilaohuguosus A-S were established by spectroscopic methods including 1D and 2D-NMR techniques and CD experiments. All isolated compounds were evaluated for their hepatoprotective activity against APAP-induced toxicity in HepG-2 cells, four 2,2'-cyclolignans, heilaohuguosus A and L, tiegusanin I and kadsuphilol I showed good hepatoprotective activities against APAP toxicity in HepG-2 cells with cell survival rates of 53.5 ± 1.7%, 55.2 ± 1.2%, 52.5 ± 2.4%, and 54.0 ± 2.2% (positive control bicyclol, 52.1 ± 1.3%) at 10 μM, respectively.