Bioactive phenolic derivatives from Acaena splendens methanol extract.

Acaena splendens H. et A. has been used in Chilean folk medicine for the treatment of fever and inflammation. A description of the in vivo reduction of bacterial pyrogen-induced fever in rabbits and carrageenan-induced paw oedema in guinea pigs is presented. The methanol extract named ME-1, obtained after succesive extractions with petroleum ether and dichloromethane, showed a strong antipyretic action (45.7% of effect), though the antiinflammatory activity was only observed after submitting this extract to column fractionation, giving a crude mixture of flavonoids named C4 with both activities (55.7% and 98.9% of antiinflammatory and antipyretic effect respectively at a dose of 600 mg/kg). The bioassay-guided fractionation by column chromatography afforded the active fraction, which contained (-,-)-epicatechin, tiliroside, 7-O-acetyl-3-O-beta-D-glucosyl-kaempferol and 7-beta-D-glucosyloxy-5-hydroxy-chromone.