Organic and Inorganic Chemistry

Biography

Biography: S. Besbes-Hentati

Abstract

Benzimidazole dimers are recognized as nucleic acid minor groove binding agents, they are strongly candidate to act via DNA or RNA grooves and can directly or indirectly recognize sequences in these grooves resulting in inhibition of transcription at A/T sites consequently an effect drug to fight cancer [1,2].

3-(4-fluorophenyl)-2-methyl-[1,2a] benzimidazolo-1,3,5-triazin-4-thione was synthesized and electrochemically oxidized in an acetonitrile solution by means of cyclic voltammetry and controlled potential electrolysis on platinum, leading to its corresponding dimer through the anodic oxidation as a deposit material. In the voltammetric study, three irreversible oxidation waves were observed. When sweeping the potential repetitively about the first anodic one, a growing film was deposited on the platinum disk. With cupper as anode, an adherent coverage by the oxidation product of the benzimidazole derivative was immediately observed, preventing the dissolution of the metallic electrode. On the preparative scale, the electrolysis at a potential located on the first wave yielded similarly to a deposit, but in addition to several oxidation products, in soluble and insoluble forms. The deposit was characterized by LC-MS and 1H NMR as a dimer formed via one electron transfer followed by a C-S linkage, an intramolecular proton transfer, a C-C coupling and an elimination of two fluorine anions. The results were rationalized on the basis of quantum-chemical calculations, using the PCM approach with the density functional theory.