Phenolic compounds with antioxidant activity from Anthemis tinctoria L. (Asteraceae).

From the aerial parts of Anthemis tinctoria L. subsp. tinctoria var. pallida DC. (Asteraceae), one new cyclitol glucoside, conduritol F-1-O-(6'-O-E-p-caffeoyl)-beta-D-glucopyranoside (1), has been isolated together with four flavonoids, nicotiflorin (2), isoquercitrin (3), rutin (4) and patulitrin (5). The structures of the isolated compounds were established by means of NMR, MS, and UV spectral analyses. Methanolic extract and pure isolated compounds were examined for their free radical, scavenging activity, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free stable radical, and for their inhibitory activity toward soybean lipoxygenase, using linoleic acid as substrate. Compounds 1 and 5 showed a strong scavenging effect in the DPPH radical assay. In addition 5 also exhibited high inhibitory activity on soybean lipoxygenase.