Electrochemical and pulse radiolysis study of misonidazole and its azo and azoxy derivatives

Pulse radiolysis experiments were carried out on methanolic solutions of misonidazole and its azo ad azoxy derivatives in order to obtain the spectra of their radical anions. The rate constants for the reaction of these compounds with e-sub(s) were 2.5 x 1010, 2.3 x 1010 and 1.9 x 1010 M-1s-1 respectively. The electrochemical properties of the compounds were studied with the aim of producing their radical anions by electrolysis in aprotic medium (DMF, 0.1 M TEAP). The potential at cathodic peaks were -1.05, -1.10 and -1.18 V for misonidazole, azo and azoxy derivatives, respectively. The decay of the radical anion of misonidazole, which produces nitrite ions, was studied in particular, the corresponding rate constant being 2.8 x 10-4 s-1. The possibility of using electrochemistry in the study of these transient species is discussed. (author)