Anti-Inflammatory Activity of a Novel Acetylene Isolated from the Roots of Angelica tenuissima Nakai

Three polyacetylenes, one novel and two known, were isolated from the root of Angelica tenuissima. Using H-1- and C-13-NMR, COSY, HMBC, and HMQC, their structures were found to be (3R,8S)-heptadeca-1-en-4,6-diyne-3,8-diol (1), falcarindiol (2), and oplopandiol (3). Absolute configurations of compound 1 were established using Mosher's esterification. In addition, the polyacetylenes (1 - 3) were evaluated for their anti-inflammatory activity. Compounds 1 and 3 showed potent inhibitory activity against lipopolysaccharide-induced nitric oxide (NO) production in RAW267.7 macrophage cells with IC50 values of 4.31 and 5.06 m, respectively. Compound 1 strongly inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 in a concentration-dependent manner.