Dibenzocyclooctadiene Lignans and Lanostane Derivatives from the Roots of Kadsura coccinea and their Protective Effects on Primary Rat Hepatocyte Injury Induced by t-Butyl Hydroperoxide

A new dibenzocyclooctadiene lignan, acetylepigomisin R (1), and a new 3,4-seco-lanostane-type triterpene, seco-coccinic acid F (2), along with three known dibenzocyclooctacliene lignans, isovaleroylbinankadsurin A (3), kadsuralignan J (4), and binankadsurin A (5), and one lanostane-type triterpene, 20(R),24(E)-3-oxo-9p-ianosta-7,24-dien-26-oic acid (6), were isolated from the methanol extract of the Kadsura coccinea roots. Their structures were elucidated on the basis of spectroscopic evidence including ESI-MS, HR-EI-MS, 1D and 2D NMR. The protective effects of these compounds were evaluated in primary cultured rat hepatocytes intoxicated with 1.2 mM t-butyl hydroperoxide. Compounds 1, 3, and 5 showed protective effects with ED50 values of 135.7, 26.1, and 79.3 mu M, respectively.