Inhibition of 3',5'–AMP Phosphodiesterase by Biflavonoids and Xanthones

Abstract
Biflavonoids and xanthones were assayed for their ability to inhibit the breakdown of cyclic AMP by a commercial beef–heart phosphodiesterase. Most of the biflavonoids were active in the micromolar range, while amento–flavone was ten times as potent; two xanthones had I50 values of about 30 μM.