Concomitant reduction of dimethylformamide and oxidation of vanadyl sulfate to N,N′-dimethylammonium decavanadate cluster and DNA, BSA binding, and cytotoxicity (HeLa) studies

Several polymetallic anionic clusters display a strong tendency to form robust ion-pairs with appropriate counter cations. We have isolated decavanadate cluster [H₂V₁₀O₂₈]^4– with, hitherto unreported, dimethylammonium ions, [N(CH₃)₂H₂]⁴⁺ as counter cations from vanadyl sulfate and N,N’-dimethylformamide (DMF). It is proposed, for the first time, that dimethylammonium ions are formed by reduction and simultaneous decarboxylation of DMF with oxidation of vanadyl sulfate occurring concomitantly under specified reaction conditions. The different colors observed during the course of the reaction are monitored by UV-Visible spectrophotometry. The structure of isolated cluster compound with four counter cations is confirmed by single crystal X-ray diffraction techniques. The compound is also tested for its DNA/BSA binding efficacy and cytotoxicity on human epitheloid cervix carcinoma (HeLa) cells along with vanadates—vanadium pentoxide and ammonium metavanadate. Based on the results, the cluster shows better IC₅₀ and binding values than vanadates.