Química medicinal

Synthesis and SAR Study of Antioxidant Potential of Polyhydroxy Coumarin Derivatives

Abstract

Badri Parshad, Arul J Duraisamy, Supriya Saini, Preeti Yadav, Praveen Vats and Sunil KS

A series of polyhydroxycoumarin derivatives, that are analogs of naturally occurring compounds, have been synthesized and their antioxidant activity (AOA) examined using DPPH, ABTS, and in vitro lipid peroxidation inhibition assays. The SAR for differently substituted polyhydroxycoumarins is reported by evaluating the positional effect of hydroxyl groups and the effect of incorporation of the lipophilic group on antioxidant activity. Many of the compounds synthesized have 4-5 fold higher AOA than ‘Trolox’ taken as standard. In DPPH and ABTS assays, the trihydroxycoumarins were observed to have a potent antioxidant activity. It has been observed that alkylation at C-3/C-4 position as well as the incorporation of pyran ring on coumarin skeleton led to the reduction in AOA in the above two assays. However, in lipid peroxidation inhibition assay an enhancement in AOA was observed for such modifications. The rationale for the observance of variation in AOA in different assays is also studied.