The process of Ni(II) ion complexation with cycloaminomethyl derivatives of 1,2-dihydroxybenzene in a water-ethanol medium was investigated. It was found potentiometrically that the complexes with the ratio M : L = 1 : 2 were formed in the solution, their overall stability constants were equal to 7,9∙10¹⁴–1,6∙10¹⁵. The Ni(II) complexes synthesized were shown to be amorphous, neutral, and thermally stable up to 150 °C. Their coordination polyhedra have the composition [NiO₂N₂] and planar square geometry. It was shown that the Ni(II) complexes demonstrate a moderate or high level of antimicrobial activity against bacteria and fungi strains tested, as well as the ability to neutralize superoxide.

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