A Novel 1,2,3-Triazole Ligand with Antioxidant Activity

The 1,2,3-triazole heterocycle serves as an important pharmacophore in large numbers of drug molecules with disparate pharmacological activities – antiviral, antibacterial, antifungal, anticancer, anticoagulant, CNS-active, to name a few. Its chemical stability, dipole moment, and ability to participate in hydrogen bonding make it an important building block for novel biologically active chemical species. The present work investigates the free-radical scavenging activity of 2-(4-methoxyphenyl)-5-(pyrrolidin-1-yl)-2H-1,2,3-triazole-4-carboxylic acid and its sodium salt. A number of free radical-generating model systems were utilized in order to estimate its potential in vitro antioxidant activity. UV-induced water radiolysis and Fenton reaction were used as sources of the physiologically important hydroxyl radical. The observed radical-scavenging activities were additionally investigated with the aid of the stable free radical model systems DPPH and ABTS in order to elucidate the possible mechanisms of radical-scavenging action. Results show that the compounds under investigation behaved as strong scavengers of hydroxyl radicals generated by UV-induced radiolysis. The effect on the Fenton reaction was close to zero or even mildly pro-oxidant; DPPH and ABTS assays showed moderate activity.