Artículo de revista
Electrochemical and ESR study of 5-nitrofuryl-containing thiosemicarbazones antiprotozoal drugs
Fecha
2005-10Registro en:
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 61 (13-14): 2933-2938
1386-1425
Autor
Rigol Olsen, Carolina
Olea Azar, Claudio
Mendizábal Emaldía, Fernando
Otero, Lucía
Gambino, Dinorah
González, M.
Cerecetto, Hugo
Institución
Resumen
Cyclic voltammetry and electron spin resonance (ESR) techniques were used in the investigation of several potential antiprotozoal thiosemicarbazones nitrofurane derivatives.
A self-protonation process involving the protonation of the nitro group due to the presence of an acidic proton in the thiosemicarbazone moiety was observed in the first step of a CEErev reduction mechanism of these derivatives.
ESR spectra of the free radicals obtained by electrolytic reduction were characterized and analyzed. AM1 methodology was used to obtain the optimized geometries and UB3LYP calculations were performed to obtain the theoretical hyperfine coupling constants. The theoretical study exhibited an unusual assignment of the spin densities showing a free radical centered in the thiosemicarbazone moiety rather than the nitro which are in agreement with the experimental hyperfine pattern.