Spasmolytic flavonols from Artemisia abrotanum.

Four flavonols with spasmolytic activity have been isolated from a methanol extract of Artemisia abrotanum L. (Asteraceae), as the principles primarily responsible for the smooth muscle relaxing activity of this plant. The flavonols show a dose-dependent relaxing effect on the carbacholine-induced contraction of guinea-pig trachea, the EC50 values for compounds 1-3 are 20-30 mumol/l while compound 4 is less active.