C2dt11731b 5248..5259 ++
نویسندگان
چکیده
Seleniumand sulfur-containing compounds can act as antioxidants by binding copper. To determine how this copper coordination results in the observed antioxidant activity, biologically relevant Cu and Cu complexes with the formulae [Cu(dmit)3] + (3), [Cu(dmise)4] + (4a), and [TpmCu(MISeox)] (6) (dmise = N,N′-dimethylimidazole selone; dmit = N,N′-dimethylimidazole thione; MISeox = bis(1methylimidazolyl)diselenide; Tpm = tris(1,3-diisopropylpyrazolyl)methane) were synthesized, characterized, and their structures determined by single-crystal X-ray crystallography. In addition, kinetic studies using UV-vis spectroscopy indicate that dmise reduces Cu to Cu three times faster than dmit. Coordination of dmise and MISeox to copper also results in more negative Cu reduction potentials (−373 mVand −503 mV) compared to dmit (−217 mV). These results highlight the different complexation behaviors and reactivities of analogous seloneand thione-containing compounds, traits which likely influence their antioxidant activity.
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