New seco-dibenzocyclooctadiene lignans with nitric oxide production inhibitory activity from the roots of Kadsura longipedunculata

Four new seco-dibenzocyclooctadiene lignans, kadlongilignans A-D (1-4), consisting of a rare 6,7-seco(1), two 15,16-seco-(2 and 3) and a 9,10-seco-dibenzocyclooctadiene (4) lignans, were isolated from the roots of Kadsura longipedunculata. Their structures were elucidated by spectroscopic analysis, including extensive NMR, MS and ECD (electronic circular dichroism) spectra. Compounds 3 and 4 exhibited potent inhibitory activities against NO (nitric oxide) production of LPS (lipopolysaccharide)-induced murine macrophages with the inhibition rates of 363% and 26.9%, respectively. (C) 2019 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.