Synthesis, structural characterization, QSAR and docking studies of a new binuclear nickel (II) complex based on the flexible tetradentate N-donor ligand as a potent antibacterial and anticancer agent

Synthesis, characterization, molecular docking, and antimicrobial activities of dinuclear nickel(ii), palladium(ii), and platinum(iv) complexes

New nickel(ii), palladium(ii), and platinum(iv) complexes were synthesized by reacting the metal ions with benzidinedioxime in a 1 : 1 mole ratio. The CHN elemental analysis, spectroscopic analyses, and powder X-ray diffraction (PXRD) results showed that two Ni(ii) and two Pd(ii) ions coordinated to two benzidinedioxime ligands via the nitrogen atoms of both oxime groups and the two azomethine nitrogen atoms. In the case of the dinuclear platinum(iv) complex, however, each Pt(iv) is coordinated with the two oxygen atoms of the oxime group and the two azomethine nitrogen atoms of the ligand. Both elemental analyses and PXRD indicated that the complex ions of Ni(ii) and Pt(iv) have distorted octahedral geometry, whereas Pd(ii) has a square planar geometry. Molecular docking studies showed that the nickel(ii) complex is the most potent dual DHPS/DHFR bacterial inhibitor. The receptor of the DHPS enzyme (3ZTE) showed the best interaction with the nickel(ii) complex when compared to a receptor of the DHFR enzyme (3FRB). All the synthesized complexes and ligand exhibited significant results against PS. Aeruginous than their corresponding SMX-TMP drug. Among the three synthesized complexes, the nickel(ii) complex possessed the highest antimicrobial activities against tested microorganisms.

Three water-soluble acylhydrazone tetranuclear transition metal complexes: Crystal structures, DNA/BSA interactions and cytotoxicity studies

2-acetylpyridine-4-chloropyridine-2‑carbonyl hydrazone (C₁₃H₁₁ClN₄O, HL) and its three water-soluble tetranuclear complexes [Cu₄(NO₃)₂(L)₄]·(NO₃)₂ (1), [Co₄(NO₃)₂(H₂O)(C₂H₅OH)(L)₄]·(NO₃)₂ (2) and [Zn₄(NO₃)₂(H₂O)(C₂H₅OH)(L)₄]·(NO₃)₂ (3) were synthesized and characterized showing that 1-3 were all tetranuclear complexes. The interactions of HL, 1-3 with calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) were explored using ultraviolet-visible (UV-Vis) titration, fluorescence spectroscopy, microcalorimetry and molecular docking techniques. The UV-Vis spectroscopy measurements showed that complexes 1-3 could strongly bind to CT-DNA by the intercalation mode, while HL interacted with CT-DNA through groove binding. From the fluorescence spectroscopy results, the interaction between HL, 1-3 and BSA was a static quenching procedure, in which complexes 1-3 had two binding sites near Trp residues of BSA while HL only had one. The microcalorimetric studies revealed that the interactions of HL and 1-3 to CT-DNA/BSA were all endothermic and the duration of each interaction was all less than 30 min. The in silico molecular docking illustrated intermolecular interactions of 1-3 binding with DNA/BSA included hydrogen bond, halogen bond, hydrophobic and electrostatic interactions. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that complex 1 possessed better cytotoxicity against HeLa, A549, MCF7 and HCT-116 than cisplatin and could be used as an alternative anticancer drug.