Limonoid constituents of Euodia rutaecarpa var. bodinieri and their inhibition on NO production in lipopolysaccharide-activated RAW264.7 macrophages

A new limonoid compound, named evorubodinin (1), was isolated from the dried and nearly ripe fruits of Euodia rutaecarpa (Juss.) Benth. var. bodinieri (Dode) Huang (family Rutaceae), together with two known limonoid compounds, limonin (2) and evolimorutanin (3). The chemical structure of 1 was elucidated by spectroscopic method and single-crystal X-ray diffraction. The inhibitory effects of the isolated compounds 1-3 and the structurally related compounds evodol (4), shihulimonin A1 (5), evodirutaenin (6), 12α-hydroxyrutaevin (7), and rutaevin (8) on nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophages were also assayed. All compounds 1-8 showed the inhibitory activity, in which both 7 and 8 with the uncommon 5β-H configuration more efficiently inhibited NO production. The results provided valuable information for further investigation of compounds 1-8 as anti-inflammatory agents or lead compounds.