摘要The anti-inflammatory phytochemical investigation of the leaves of Illicium dunnianum(I.dunnianum)resulted in the isolation of five pairs of new lignans(1-5),and 7 known analogs(6-12).The separation of enantiomer mixtures 1-5 to 1a/1b-5a/5b was achieved using a chiral column with acetonitrile-water mixtures as eluents.The planar structures of 1-2 were previously undescribed,and the chiral separation and absolute configurations of 3-5 were re-ported for the first time.Their structures were determined through comprehensive spectro-scopic data analysis[nuclear magnetic resonance(NMR),high-resolution electrospray ioniza-tion mass(HR-ESI-MS),infrared(IR),and ultraviolet(UV)]and quantum chemistry calcula-tions(ECD).The new isolates were evaluated by measuring their inhibitory effect on NO in lipopolysaccharide(LPS)-stimulated BV-2 cells.Compounds 1a,3a,3b,and 5a demonstrated partial inhibition of NO production in a concentration-dependent manner.Western blot and real-time polymerase chain reaction(PCR)assays revealed that 1a down-regulated the mes-senger ribonucleic acid(mRNA)levels of tumor necrosis factor α(TNF-α),interleukin-6(IL-6),COX-2,and iNOS and the protein expressions of COX-2 and iNOS.This research provides guidance and evidence for the further development and utilization of I.dunnianum.