Complexation behavior of copper and zinc divalent ions towards diisatin malonyl dihydrazone ligand with biological and catalytic assessments

Abstract

According to the interesting reactivity of arylhydrazones in coordination chemistry and biological assays, malonyl dihydrazone ligand of diisatin derivative (H 2 Lm) was reacted with Cu 2+ and Zn 2+ ions forming two complexes of dinuclear homoleptic mode (CuLm and ZnLm, respectively). Demonstration of their chemical structures was confirmed through various spectroscopic ways alongside the elemental analyses (EA), conductivity measurements, and magnetic characteristics. Their bio‐performance was recorded based on their inhibited potential of the growing ability of some common bacteria, fungi, and human cancer/normal cell lines. The biological studies appointed the role and job of M 2+ ion = Cu 2+ or Zn 2+ in its chelated MLm complex to perform the bio‐reactivity over the free ligand, H 2 Lm. Moreover, their interacted modes with ct DNA (i.e., calf thymus DNA) were examined via the viscometry and spectrophotometric titration. Because the two chelates (CuLm and ZnLm) represented an attractive job for the inhibited action against the current microorganisms and the human cancer/normal strains' growth over the free H 2 Lm ligand, CuLm and ZnLm complexes displayed a distinguished interaction with ct DNA more than that of their uncoordinated H 2 Lm ligand. From the values of binding constant ( K b ) and Gibb's free energy ( ), CuLm assigned more bio‐action within ct DNA more than ZnLm H 2 Lm ligand, referring to the role of Cu 2+ ion with more electronegativity to enhance the reactivity of CuLm over their free H 2 Lm ligand and ZnLm. The catalytic behavior of CuLm and ZnLm was given within the epoxidation of 1,2‐cyclohexene (an example of unsaturated hydrocarbons) homogeneously using hydrogen peroxide (the oxidant). Their catalytic action was optimized through various temperatures, solvents, time, and type of M 2+ ion in the catalyst.