Illiciumlignans G-O from the leaves of Illicium dunnianum and their anti-inflammatory activities.

Phytochemical investigations on the dry leaves of Illicium dunnianum have led to the isolation of 24 lignans. Illiciumlignans G-K (1-5) were five undescribed benzofuran lignans, illiciumlignan L (6) was one undescribed ditetrahydrofuran lignan, illiciumlignans M-O (7-9) were three new sesquilignans, and compounds 10, 12, 13, 15, and 18-21 were firstly isolated from the genus Illicium. Their structures were elucidated by detailed spectroscopic analyses (UV, IR, HR-ESI-MS, and NMR) and CD experiments. All isolates were evaluated by measuring their inhibitory effects on PGE2, and NO production in LPS-stimulated RAW 264.7 macrophages.