3,3′,4′,5,5′-Pentahydroxyflavone is a potent inhibitor of amyloid β fibril formation

► We synthesized a series of fisetin analogues lacking the 7-hydroxyl group. ► The 7-hydroxy group was not necessary for anti-amyloidogenic activity of flavonoids. ► 3,3′,4′,5,5′-Pentahydroxyflavone was the most potent inhibitor of Aβ fibrillization.