Synthesis, characterization, DFT calculation, DNA binding and antimicrobial activities of metal complexes of dimedone arylhydrazone

Abstract

The diazotization, coupling and metallization process was employed to create hydrazone chelating ligand (HL) and its Co(II), Cu(II) and Ni(II) complexes. Elemental analysis, FT-IR, UV–visible, thermal analysis, 1H NMR, and 13C NMR were utilized to propose their structures. The reaction between metal (II) with HL produced mononuclear complexes and the molar conductivity results demonstrated that the complexes are all non-electrolytes that fall within a certain range 8–12 Ω−1 cm2 mol−1. Co(II) and Ni(II) complexes have pseudooctahedral coordination geometry, whereas Cu(II) complexes have square planar coordination geometry. The metal ion interacts with the ligand. as a monobasic bidentate by (CO) as well as deprotonating hydrazone moiety (NH). Besides, the optimized structure, bond lengths, and angles of the ligand and its complexes determined quantum chemical parameters were estimated by molecular modeling. Electronic absorption dilution and viscosity analysis techniques were used to study the compounds' DNA binding activities. With a binding constant in the 5.13 × 105 M−1 range. The results revealed that the complexes bind to CT-DNA in grooves followed by partial incorporation of the ligand between the DNA base stacks. The cytotoxicity of the new complexes was examined versus human carcinoma cell lines, HepG-2 & MCF-7, and compared to positive controls as vinblastine and colchicine. The DPPH free radical-scavenging assay was used to evaluate the anti-oxidant capacity of all compounds in-vitro. Finally, the antimicrobial activities of the complexes against fungal (Candida albicans), gram negative bacteria (Escherichia coli), and gram positive bacteria (Escherichia coli) were investigated using the disc-diffusion process (Staphylococcus aureus).