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

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(-6) mol/L, with its IC50 values of 0.22-8.8×10(-2) μmol/L.