Coreosides A–D, C14-polyacetylene glycosides from the capitula of Coreopsis tinctoria and its anti-inflammatory activity against COX-2

Abstract

Four new C14-polyacetylene glycosides, namely coreosides A–D (1–4), were isolated from the capitula of Coreopsis tinctoria, a Snow chrysanthemum or Snow tea that is used as a folk tea for prevention of cardiovascular disease in southern Xinjiang, China. Coreosides A–D feature a long chain structure as its aglycon with two acetylenes on C-8 and C-10 and two olefinics on C-6 and C-12 sites, which construct a large conjugate system. The structures were elucidated on the basis of spectroscopic evidences and hydrolysis. Compounds 1–4 exhibited significant inhibition against cyclooxygenase-2 at the concentration of 1×10−6mol/L, with its IC50 values of 0.22–8.8×10−2μmol/L.