Free radical scavenging activity of novel thiazolidine-2,4-dione derivatives

ABSTRACT Free radical activity towards superoxide anion radical (O2•¯), hydroxyl radical (HO•) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH•) of a series of novel thiazolidine‐2,4‐dione derivatives (TSs) was examined using chemiluminescence, electron paramagnetic resonance (EPR) and EPR spin trapping techniques. 5,5‐Dimethyl‐1‐pyrroline‐N‐oxide (DMPO) was applied as the spin trap. Superoxide radical was produced in the potassium superoxide/18‐crown‐6 ether dissolved in dimethyl sulfoxide. Hydroxyl radical was generated in the Fenton reaction (Fe(II) + H2O2. It was found that TSs showed a slight scavenging effect (15–38% reduction at 2.5 mmol/L concentration) of the DPPH radical and a high scavenging effect of O2•¯ (41–88%). The tested compounds showed inhibition of HO• ‐dependent DMPO‐OH spin adduct formation (the amplitude of EPR signal decrease ranged from 20 to 76% at 2.5 mmol/L concentration. Our findings present new group compounds of relatively high reactivity towards free radicals. Copyright © 2012 John Wiley & Sons, Ltd.