Voltammetric Study and Kinetic Stability of Nitro Anion Radical in Aqueous Media of Two New Sulfonylhydrazone Derivatives with Potential Anti-Chagas Activity

Abstract Two new sulfonylhydrazone derivatives, analogues of nitrofurazone, with potentially antichagasic biological activity were studied by cyclic voltammetry, having glassy carbon as working electrode, in aqueous media aiming at a better understanding of their redox mechanism that can be related to the biological action, being classically characterized by charge transfer processes. In an acidic medium, an irreversible cathodic peak corresponding to the formation of hydroxylamine derivative was observed, being linearly displaced with the decrease in the acidity of the medium to more negative potential values. In alkaline medium, the reduction was independent of the pH, registering the formation of the reversible \(\text{R-N}{\text{O}}_{2}/\text{R-N}{\text{O}}_{2}^{-}\) couple. The half-life of the nitro-anion radical was experimentally estimated and corroborated by simulation with Digisim.