Synthesis and antioxidant properties of substituted 3-benzylidene-7-alkoxychroman-4-ones.

A series of 3-benzylidene-7-alkoxychroman-4-one derivatives were synthesized and evaluated for their antioxidant activities. The antioxidant activity was assessed using three methods, namely, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP), and thiobarbituric acid reactive substances (TBARS) assays. 3-Benzylidene-7-alkoxychroman-4-one derivatives bearing catecholic group on benzylidene moiety exhibited excellent antioxidant activity. Compounds having catechol moiety exhibited potent antioxidant activities in all tested methods and they were more active than the reference drug, Trolox.