ent-Abietane-type diterpenoids from the roots of Euphorbia ebracteolata with their inhibitory activities on LPS-induced NO production in RAW 264.7 macrophages

Ten ent-abietane diterpenoids (1-10), including four new (1-4) and six known ones (5-10) were isolated from the roots of Euphorbia ebracteolata. Their structures were determined by 1D, 2D NMR, and HRESIMS. Compounds 2, 4, and 7 exhibited significant inhibitory activities on lipopolysaccharide (LPS)-induced nitric oxide production in RAW 264.7 macrophages with IC50 values of 0.69, 1.97, and 0.88 mu M, respectively. A primary structure-activity relationship was also discussed. (C) 2015 Elsevier Ltd. All rights reserved.