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ABSTRACT The current investigation involved the synthesis and detailed characterization of novel mixed‐ligand complexes of Mn(II) (MnDPPNPH) and Cu(II) (CuDPPNPH). These complexes incorporate 2,6‐di(1H‐pyrazol‐1‐yl)pyridine (DPP) and a Schiff base derived from 2‐hydroxy naphthaldehyde (NPH). The synthesized complexes revealed a stoichiometric ratio of 1:1:1 (metal:DPP:NPH), indicative of an octahedral coordination geometry around the Mn(II) and Cu(II) centers, as represented by the chemical formula [M (DPP)(NPH)(Cl)]. To elucidate their structural and electronic properties, theoretical calculations were performed. These calculations facilitated the optimization of the geometrical structures and provided insights into the molecular orbital characteristics of the complexes. The MnDPPNPH and CuDPPNPH complexes demonstrated potential phenoxazinone synthase mimicking activity by catalyzing aerial coupling of o‐aminophenol (OAPh) to form phenoxazine‐2‐one (phenox). The mimicking activity of these complexes was quantitatively assessed using Michaelis–Menten enzymatic kinetics. Various enzyme kinetics plots were employed to determine several kinetic parameters, including the specificity constant and turnover number (kcat), which are crucial for understanding the efficiency of the catalytic cycles. Remarkably, the synthesized MnDPPNPH and CuDPPNPH complexes exhibited significantly higher turnover numbers (kcat) compared to previously reported complexes. This finding suggests that these new complexes possess superior catalytic activity, highlighting their potential as effective catalysts for reactions mimicking the function of phenoxazinone synthase. [ABSTRACT FROM AUTHOR]

Novel divalent chelates of Co (II), Cu (II), Zn (II) and Ni (II) were prepared and described of the form [M (NTM)(CH3COO)2] where NTM = [1‐(4‐nitrophenyl)‐1H‐1,2,3‐triazol‐4‐yl)methanol ligand. Elemental analyses, infrared red, 1H and 13CNMR, electronic, magnetic susceptibility, conductivity measurements and X‐ray diffraction studies were used to assess our divalent metal complexes. Moreover, the stability and stoichiometry of the novel metal chelates were examined through the job's method in solutions. Correlation of all spectroscopic techniques states that NTM acts as a bi‐dentate NO ligand to afford octahedral complex geometry for all the investigated metal chelates. Thermodynamic and kinetics factors for various thermal degradation phases were calculated. Moreover, B3LYP/LANL2DZ/6‐311 g(d,p) theoretical study has been applied for estimating the MEP and quantum chemical reactivity descriptors of studied molecules. Moreover, the UV–Vis absorption spectra for the investigated molecules are predicted via the time‐dependent DFT (TD‐DFT) calculations. In addition, MOE‐ docking was tested on two different proteins, the receptor of (3HB5) breast cancer mutant oxidoreductase as well as the receptor of Glucosamine‐6‐phosphate synthase in complex with glucosamine‐6‐ phosphate of (2VF5) E.coli and COVID‐19 protease. The results recommended that the (NTMCo), (NTMNi), (NTMCu) and (NTMZn) complexes showed the highest inhibitory activity compared to the other NTM ligands as antimicrobial and breast cancer candidates. Furthermore, in‐vitro anti‐bacterial, anti‐fungal, cytotoxic and anti‐oxidant performances for the selected ligand as well as its chelates were studied. All metal chelates presented superiority, proceeding free organic ligand ineffective management, definitely NTMCu complex. [ABSTRACT FROM AUTHOR]

The primary objective of the current framework was to synthesize novel mononuclear 1:1:1 complexes involving FeLG, CoLG, NiLG, CuLG, and ZnLG, where the ligand (L) is identified as 4-[(4-oxo-4,5-dihydro-1,3-thiazol-2-yl)hydrazono]methylphenyl-4-methylbenzenesulfonate, and glycine (G) serves as the coligand. Comprehensive characterization of the investigated complexes was achieved through various analytical techniques, including FTIR, UV-Vis spectroscopy, elemental analysis, mass spectra, magnetic susceptibility measurements, molar conductivity assessments, and thermogravimetric analysis (TGA). The determination of stoichiometry was performed employing the molar ratio technique, revealing the octahedral geometry inherent in the isolated metal complexes. Employing a density functional theory (DFT) approach, the molecular structures of the designated compounds were theoretically elevated, and quantum chemical descriptors were derived to provide a deeper insight into their electronic properties. Furthermore, the inhibitory potential of these compounds against fungal strains and pathogenic bacteria prevalent in the Arab environment was evaluated using the disc diffusion method, emphasizing their role in combating diseases affecting humans, animals, and plants. Notably, the metal complexes exhibited superior antibacterial activity, as evidenced by a higher activity index. Molecular docking investigations were conducted to ascertain the inhibitory effects of the compounds on the 1FJ4 protein, with ZnLG emerging as the compound with the highest binding affinity. These results suggest the promising candidacy of these compounds as antimicrobial agents, particularly in the context of combating bacterial and fungal infections. [ABSTRACT FROM AUTHOR]

New 2-[(4-[(4-methylphenyl)sulfonothioyl)methylene]aminobenzoic acid ligand-Co(II), Ni(II), and Cu(II) complexes are synthesized and characterized in this article. Elemental analysis, mass spectroscopy, conductivity tests, magnetic susceptibility, Fourier transform infrared spectroscopy, thermogravimetric analysis, electronic absorption spectroscopy, and density functional theory calculations were used to determine the coordination mode, and geometry of the synthesized compounds. The Schiff-base ligand was shown to be mononegatively charged and coordinate to metal ions in a bi-dentate mode through azomethine nitrogen (-CH=N-) and carboxylic Oxygen (-COOH). Density functional theory (DFT) calculations were performed in addition to the experimental data to assess the most probable structures of the complexes. In addition, the biological activities of these compounds were evaluated by in vitro antibacterial and antifungal assays. These novel Co(II), Ni(II), and Cu(II) compounds were shown to be active against a wide variety of microorganisms, including Gram-positive and Gram-negative bacteria, as well as fungi. Following that, molecular docking was used to analyze the complexes' interactions with bacterial proteins, validating the therapeutic potential of the metal-containing compounds. [ABSTRACT FROM AUTHOR]

The present framework has as its goal the design and synthesis and characterization of new mononuclear 1:1:1 (M:L:Q) mixed-ligand complexes, including FeLQ, CoLQ, NiLQ, CuLQ, and ZnLQ. The "L," is the 4-[(4-oxo-4,5-dihydro-1,3-thiazol-2-yl)hydrazono]methylphenyl 4-methylbenzenesulfonate, while the "Q," is the 8-hydroxy quinoline. According to the findings, L and Q ligands each play the role of a neutral bi-dentate NN and a monobasic bi-dentate ON ligand, respectively. The findings demonstrated an octahedral shape. The density functional theory (DFT) technique was employed, and the quantum chemical descriptors were assessed, to optimize the molecular structure of the compounds. An in vitro investigation was carried out to investigate the antibacterial and antifungal activities of the compounds. According to the findings, the activity of metal complexes as potential candidates for use as antibiotics and antifungals is much greater than that of their free ligands. The in-silico inhibition of the 1fj4 protein was investigated using molecular docking. ZnLQ complex was the one that inhibited the 1fj4 protein with the greatest degree of success. The fact that this is the case lends credence to the notion that these compounds have the potential to function as launchpads for the development of new classes of antibiotics. [ABSTRACT FROM AUTHOR]