Synthesis, biological evaluation and quantitative structure-activities relationship of flavonoids as vasorelaxant agents.

A series of flavonoid derivatives were designed, synthesized. Their vasorelaxant activities were evaluated experimentally against rat aorta rings pretreated with phenylephrine (PE). Among them, 6-hydroxy-8-allyl-4'-chloro-flavanone 8q exhibited the highest vasodilatory activity (EC(50)=4.6 microM, E(max)=95.1%). The 3D-QSAR analysis was carried out by comparative molecular field analysis (CoMFA) method, and a statistically reliable model with good predictive power (r(2)=0.872 and q(cv)(2)=0.496) was established. The contour plots of CoMFA model provide a good insight into the structure-activity relationships of these compounds and may be used to design more potent flavonoids derivatives as vasorelaxant agents.