Synthesis, characterization, crystal structure, electrochemical and photoluminescence properties, DFT and molecular docking studies, and antimicrobial activities of two mononuclear nickel (II) complexes with Pyrazole-derived ligands
Articles > Article · 2025
Authors: Mina A. Amin, Halide DİKER, Onur Şahin, Canan Varlikli, Ahmed A. Soliman
Journal of Molecular Structure, Journal Indexed in SCI Expanded, International, WoS, 2025, vol 1342, pp 142763-142763
DOI: 10.1016/j.molstruc.2025.142763
Summary
Two octahedral nickel complexes; [Ni(fdtp)2(DMF)2] (1) and [Ni(dcdtp)2(DMF)2] (2), based on 4-((3-fluorophenyl)diazenyl)-3-(trifluoromethyl)-1H-pyrazol-5-ol (fdtp) and 4-((2,4-dichlorophenyl)diazenyl)-3-(trifluoromethyl)-1H-pyrazol-5-ol (dcdtp) were synthesized. The complexes were characterized spectroscopically (FTIR, UV–Vis, Photoluminescence), Mass spectrometry, elemental analyses, electrochemically, thermally, and through Single-crystal X-ray investigations. The formation of the complexes was confirmed by the existence of Ni–O and Ni–N vibrations at bonds were observed as weak bands at 526–497 and 470–438 cm–1. According to the thermogravimetric analyses, the complexes were thermally stable and had relatively high activation energies (585.81 and 730.07 kJ mol–1 for 1, and 2, respectively). Cyclic voltammograms showed that the anodic potential region of 1 and 2 exhibited two irreversible oxidation peaks at 1.34 V &1.55 V and 1.41 V & 1.63 V, respectively, attributed to metal-localized oxidation. The complexes showed enhanced antibacterial activities compared to free ligands and comparable to the standard. The inhibition zones exhibited via 1 were about 21.7, 19.3, and 26.7 mm versus Escherichia coli (E. coli), Staphylococcus aureus (S. Aureus), and Bacillus Subtits (B. Subtits), respectively. Docking studies supported the antibacterial investigations; the binding energies of the complexes were -8.81 and -9.69 kcal/mol for 1 and 2 respectively, against E. coli (PDB ID: 6F86).