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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]

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]

The aim of the present framework is to synthesize and characterize new cobalt(II) (C1), nickel(II) (C2), and copper(II) (C3) mixed‐ligand complexes incorporating bioactive 8‐hydroxyquinoline moiety, with synthesized 2‐(1H‐benzimidazol‐2‐yl)guanidine (BG) ligand, for investigating their antibacterial, antifungal, and anti‐inflammatory potential. The metal complexes structure had been elucidated by the use of a wide range of methods, including elemental analysis, Fourier transform infrared (FT‐IR), mass spectra, UV–vis spectra, magnetic susceptibility, thermogravimetric (TG) analysis, and the molar ratio technique of stoichiometry analysis. The resulted metal complexes were found to have octahedral structures in molar ratio of M:BG:Qu as 1:1:2. Density functional theory (DFT) had been used to determine the optimal molecular structure and quantum chemical properties of each material. After that, we looked into the metal complexes' anti‐inflammatory and antibacterial properties by testing them in vitro. The disc diffusion test showed that the metal complexes were far more potent against bacteria/fungi than the original ligands. The egg albumin denaturation technique showed that the metal complexes were more potent anti‐inflammatory candidates than the free ligands and comparable with the standard reference. Molecular docking analysis against 5JQ9, 6CLV, and cyclooxygenase‐2 (COX‐2; 5IKT) confirmed the bioactivity behavior of the metal complexes. C3 has the greatest binding affinity among the metal complexes tested. These findings proposed that the metal complexes could form the basis of future antibiotics and anti‐inflammatory candidates. Finally, the in vitro activities were reviewed in relation to the DFT and molecular docking data. [ABSTRACT FROM AUTHOR]

The mpox (previously monkeypox) outbreak in more than 100 non-endemic countries in 2022 posed a serious global health concern. Mpox is emerging as a global public health threat from a seemingly neglected disease. A42R profilin-like protein from mpox virus (PDB ID: 4QWO) could be a preferred target lead. The binding affinity of commonly used drugs/mAbs (tecovirimat, brincidofovir, cidofovir) for A42R profilin-like protein was examined in silico through molecular docking. Further, the results were compared with those of the phytochemicals curcumin, rutin, and theaflavin. Tecovirimat (-7.31 kcal/mol, IC50 = 4.39 lM) and theaflavin (-6.99 kcal/mol, IC50 = 7.54 lM) had the highest affinities. Molecular dynamics simulation of the theaflavin-4QWO complex was performed to ascertain the stability of ligand-protein interactions in natural charge, molecular electrostatic potential, and frontier molecular orbital analyses. The predicted QSAR and pharmacokinetic properties of all compounds were evaluated to find a suitable candidate for designing and developing new drugs. The evaluated log P values for brincidofovir and tecovirimat were higher than those of the other drugs in the QSAR study. Theaflavin had an impressive log P of 4.77, which hints at its high biological activity. The findings recommend further in vitro experimental validation to develop potential low-cost mpox therapies. [ABSTRACT FROM AUTHOR]

The main purpose of the current work is the design and synthesis of new Co(II), Ni(II), and Cu(II) mixed‐ligand complexes derived from simple and easily synthesized azo‐ligand, [2‐(phenylthio)phenyl]diazenyl}‐2‐naphthol (HTe), with 8‐hydroxyquinoline (HQ) to improve and understanding their action as an antimicrobial candidate and their therapeutic efficiency with the aid of density functional theory (DFT) calculations and molecular docking studies, which considered a hot topic of research. To access this target, and to explore the effect of changing metal ion type, the new Co(II), Ni(II), and Cu(II) mixed‐ligand complexes were firstly synthesized and characterized via elemental analysis, Fourier transform infrared (FT‐IR), mass spectrometry, ultraviolet–visible spectroscopy, magnetic susceptibility, thermogravimetric analysis (TGA), and stoichiometry analysis molar ratio method. Upon further inspection, the octahedral structures of the isolated metal complexes were found. The compounds' molecular structures were optimized using the DFT technique, and the quantum chemical parameters were evaluated. To determine whether or not these compounds are effective in preventing the spread of harmful bacteria and fungi, two of the most common environmental pollutants in the Arab world, a disc diffusion test was conducted. The prepared complexes were much more efficient against bacteria than the pristine ligands. Molecular docking experiments helped researchers learn which medicines inhibited the 1fj4 protein. All other tested compounds were found to have lower binding affinities than CuTeQ. This suggests that these compounds have the potential as starting points for the production of new classes of antibiotics. Finally, a correlation of the in vitro activity with the DFT and molecular docking data has been done and discussed. [ABSTRACT FROM AUTHOR]

Simple Summary: The coronavirus was declared a worldwide pandemic for the first time in December 2019. Although vaccination reduces the risk of severe illness and death, no vaccine is 100% foolproof. Recently, the COVID-19 primary protease has become a promising therapeutic target. During the preceding three years, many low molecular weight chemical libraries were tested for their potent antiviral potency against SARS-CoV-2. Many studies focused on organoselenium compounds due to their potential antiviral activities. Herein, new organoselenium-based Schiff bases were successfully synthesized and evaluated for their potential to inhibit the SARS-CoV-2 Mpro main protease, which is essential for virus replication. Since the first report of the organoselenium compound, ebselen, as a potent inhibitor of the SARS-CoV-2 Mpro main protease by Z. Jin et al. (Nature, 2020), different OSe analogs have been developed and evaluated for their anti-COVID-19 activities. Herein, organoselenium-clubbed Schiff bases were synthesized in good yields (up to 87%) and characterized using different spectroscopic techniques. Their geometries were studied by DFT using the B3LYP/6–311 (d, p) approach. Ten FDA-approved drugs targeting COVID-19 were used as model pharmacophores to interpret the binding requirements of COVID-19 inhibitors. The antiviral efficiency of the novel organoselenium compounds was assessed by molecular docking against the 6LU7 protein to investigate their possible interactions. Our results showed that the COVID-19 primary protease bound to organoselenium ligands with high binding energy scores ranging from −8.19 to −7.33 Kcal/mol for 4c and 4a to −6.10 to −6.20 Kcal/mol for 6b and 6a. Furthermore, the docking data showed that 4c and 4a are good Mpro inhibitors. Moreover, the drug-likeness studies, including Lipinski's rule and ADMET properties, were also assessed. Interestingly, the organoselenium candidates manifested solid pharmacokinetic qualities in the ADMET studies. Overall, the results demonstrated that the organoselenium-based Schiff bases might serve as possible drugs for the COVID-19 epidemic. [ABSTRACT FROM AUTHOR]

Novelmanganese(II), iron(III), cobalt(II), nickel(II), and copper(II) chelates were synthesized and studied using elemental analysis (EA), infrared spectroscopy, mass spectrometry, ultraviolet-visible spectroscopy, and conductivity, as well as magnetic measurements and thermogravimetric analysis (TG). The azo-ligand 1-[(4-nitrophenyl)diazenyl]-2-naphthol (HL) chelates to the metal ions via the nitrogen and oxygen centers of the azo group and the hydroxyl, respectively. The amounts of H2O present and its precise position were identified by thermal analysis. Density functional theory (DFT) was employed to theoretically elucidate the molecular structures of the ligand and the metal complexes. Furthermore, the quantum chemical parameters were also evaluated. The antimicrobial properties were evaluated against a group of fungal and bacterial microbes. Interestingly, the bioactivity of the complexes is enhanced compared to free ligands. Within this context, the CuL complex manifested the lowest activity, whereas the FeL complex had the greatest. Molecular docking was used to foretell the drugs' binding affinity for the structure of Escherichia coli (PDB ID: 1hnj). Protein-substrate interactions were resolved, and binding energies were accordingly calculated. [ABSTRACT FROM AUTHOR]

Two new Fe (III) and Cr (III) complexes had been synthesized and structurally characterized. The new complexes were based on 2‐methyl‐benzimidazole (MB) and salicylic acid (H2L). Elemental analyses, Fourier transform infrared spectroscopy, UV‐–Vis, mass spectra, conductivity, magnetic, and thermal measurements were used to formulate the compounds structures. The results revealed octahedral geometry for both of Fe (III) and Cr (III) complexes. Structure elucidation of these complexes was also supported by density functional theory (DFT) along with optimized geometrical parameters. Natural bond orbital analysis and molecular electrostatic potential were also investigated. Electronic absorption spectra were theoretically performed using the time‐dependent TD‐DFT/B3LYP in gas phase and acetonitrtile as a solvent. Furthermore, the bio‐mimicking activity as antimicrobial and anti‐inflammatory activity of the understudy compounds was in vitro screened. The results showed that the Fe (III) and Cr (III) complexes exhibited higher pathogenic action than the free ligands. Molecular docking investigation against 3T88 (E. Coli) and 5IKT (Cyclooxygenase‐2) was carried out to provide deep insights into their role in inhibiting the growth of pathogenic microbes. [ABSTRACT FROM AUTHOR]

Herein, new Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) complexes incorporating 4‐{[(2‐hydroxyphenyl)imino]methyl}phenyl 4‐methylbenzenesulfonate Schiff‐base ligand (HL) were designed, synthesized, and characterized. The structure of the new compounds was elucidated based on spectroscopic techniques (nuclear magnetic resonance [NMR], ultraviolet–visible [UV‐vis], infrared [IR], mass), magnetic, conductivity, thermal analysis (thermogravimetric analysis [TGA], differential thermal analysis [DTA]) measurements, in addition to complex stoichiometry determination using molar ratio and Job's methods. The new complexes showed an interesting structural variation: square‐planar (in the case of NiL), tetrahedral (in the case of CuL), and octahedral (in the case of FeL2, CoL2, and ZnL2). Furthermore, density functional theory (DFT) calculations were performed to obtain deep insights into the structural features, orbital interactions, and electronic chemical descriptors evaluation. Moreover, the anti‐inflammatory behavior of the titled compounds was in vitro investigated. Interestingly, the ZnL2 complex showed the highest activity, whereas the CuL complex showed the lowest activity compared with the other compounds. In order to ascertain the bioactivity of the present compounds, their efficacy was compared with previously reported compounds showing high activity. The anti‐inflammatory activity was supported by molecular docking analysis against cyclooxygenase‐2 (COX‐2) enzyme (PDB ID: 5IKT), which confirms the bioactivity behavior. The obtained results indicated that the titled compounds could be promising anti‐inflammatory candidates. [ABSTRACT FROM AUTHOR]

The present paper deals with synthesis new mononuclear 1:1:1 metal:ligand:co‐ligand complexes, FeLG, NiLG, and CuLG, where L = 1‐{(E)‐[(4‐methylphenyl)imino]methyl}‐2‐naphthol and G = Glycine. The synthesized complexes were characterized based on elemental analysis, Fourier transform infrared spectroscopy (FT‐IR), ultraviolet–visible (UV–vis), mass spectra, molar conductance, magnetic susceptibility, and thermal analysis (TGA) in addition to stoichiometry determination via molar ratio method. The isolated metal complexes showed interesting geometry variation as tetrahedral for CuLG and octahedral for both FeLG and NiLG. The molecular structures of the titled compounds were optimized theoretically using density functional theory (DFT) approach, and the quantum chemical descriptors were calculated. The disk diffusion method was used to investigate the growth inhibition of the titled compounds aganist selected pathogenic bacterial and fungal strains. The metal complexes exhibited higher enhancement as antimicrobial candidates with lower minimum inhibitory concentration (MIC) than the free ligands, and in some cases, the complexes were closed to the standard species. Molecular docking investigation was carried out to ascertain the inhibitory action of the studied compounds against 1HNJ protein, the target enzyme for the antimicrobial agents. The results indicated that the FeLG has the highest binding affinity in comparison with other compounds. Thus, these molecules could be promising antimicrobial candidates. Furthermore, catalase mimicking activity of the complexes has been investigated. The data revealed that CuLG complex catalyzes the decomposition of hydrogen peroxide most effectively. Finally, the quantum chemical parameters of the titled complexes and other different compounds were correlated with their practical biological activity data in a trial to build a SAR model. [ABSTRACT FROM AUTHOR]

[Display omitted] • New Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), and Zn(II) complexes were synthesized and characterized. • 3D geometry was optimized using DFT approach. • In vitro antimicrobial activity was screened. • Molecular docking against 1HNJ protein was explored. • Drug-Likeness properties were investigated based on Lipinski rule. Herein, new Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes based on azocoumarin ligand, 2-[(E)-(2-oxo-2H-chromen-6-yl)diazenyl]-1-phenylbutane-1,3-dione (L), were synthesized and characterized via elemental analyses, IR, mass, UV–Vis spectra, magnetic susceptibility, conductivity measurements, and thermogravimetric analysis (TG). From IR spectra, it was elucidated that the azocoumarin ligand behaves as a neutral bi-dentate ligand and coordinates to the metal ions through the azo Nitrogen and carbonyl Oxygen. Number and position of the water molecules were investigated through thermal analysis. The molecular structures of the ligand (L) and its metal complexes were optimized theoretically using density functional theory (DFT) for various possible orientations of the H 2 O and Cl moieties around the metal-center, to find out the most reliable coordination modes. Moreover, the quantum chemical parameters were evaluated. The bioactivity of the ligand and its complexes were screened for their in vitro anti-bacterial and anti-fungal activity against series of pathogenic bacterial and fungal strains. The metal complexes possess high biological activity with low minimum inhibition concentration (MIC) against different organisms. In order to ascertain the bio-effect of the present compounds, their MIC was compared with previously reported MIC showing lower MIC values. Molecular docking was used to predict the binding efficiency between the prepared compounds and the receptor of E. coli (1HNJ), the target enzyme for the antimicrobial reagents. The protein-substrate interactions were investigated and the binding energies were calculated. The drug-likeness and ADMET prediction showed compliance with the Lipinski rule, and the compounds were found to have good absorption, distribution, metabolism, and excretion generally. The results were very encouraging, so we can say that these products are biologically active and can be used later in other applications towards drug development. [ABSTRACT FROM AUTHOR]

• New FeLphen, Colphen and Nilphen complexes were synthesized, characterized and theoretically investigated. • Optimization and vibrational study of the new compounds were performed using DFT approach. • The reactivity of the new compounds was evaluated using frontier orbitals studies. • In vitro evaluation of the synthesized compounds shows a good antimicrobial activity. • Molecular docking against 2VF5, 4FXQ, and 3cku was explored. • The experimental results are in good agreement with the theoretical investigation. Three new FeLphen, CoLphen and NiLphen hetero-ligand were synthesized, characterized and theoretically investigated. The new complexes were based on phenylalanine (Hphen) and 1-{(E)-[(4- methylphenyl) imino ]methyl}-2-naphthol Schiff-base (HL). The results showed interesting structural variety as octahedral for FeLphen ([F e (L)(phen)(C l)(H 2 O)]), CoLphen ([C o (L)(phen)(H 2 O) 2 ]) and tetrahedral for NiLphen ([N i (L)(phen)]). The molecular properties, geometric optimization, vibrational, frontier molecular orbital, and energy evaluation of the new complexes were characterized theoretically using density functional theory (DFT) approach. The calculations were performed to find out the most reliable cis /trans (Chloride and/or H 2 O) and the (HL/Hphen) orientations around the Fe(III)/Co(II) and Ni(II) center. The calculations revealed that trans-H 2 O/Cl-cis-N HL /N Hphen & cis-H 2 O/H 2 O-cis-N HL /N Hphen and cis-N HL /N Hphen were the most stable orientations for the FeLphen, CoLphen and NiLphen, respectively. Furthermore, the antibacterial and antifungal activity of the titled compounds was in vitro screened. The results showed that the metal complexes exhibited higher pathogenic effect than the free ligands against the selected microbes. Molecular docking investigation against 2VF5, 4FXQ, and 3cku, was carried out to provide deep insights into their role in inhibiting the growth of pathogenic microbes. Comparative analysis elucidated higher antibacterial and antifungal activity of the titled compounds compared with literature survey. [Display omitted] [ABSTRACT FROM AUTHOR]

Computational exploration has been carried out on three p-tertbutylthiacalix[4]arene derivatives, namely cone (a), partial-cone (b), and 1,3-alternate (c). These three compounds are recently synthesized in high yields (80, 95, and 85%, respectively) and characterized by our group, which showed high uptake efficacy of alkali, heavy, and transition metal ions via liquid–liquid extraction. Significantly, these compounds exhibited high uptake capacity for Cu(II) (74.9 %) and Pb(II) (80.0%) upon using cone (a), and partial-cone (b), respectively. In this study, in order to optimize how the thiacalix[4]arene (as a nucleophilic) interacts with the metal ion (as an electrophile), DFT calculations were undertaken. Theoretical IR and UV–Vis spectral features of the titled compounds were computed and compared with their experimental values. Chemical reactivity was ranked based on selected electronic chemical descriptors. Moreover, the active sites of the three compounds were determined by molecular electrostatic potential (MEP) maps. Furthermore, non-linear optical (NLO) properties were investigated and compared with urea as reference material. The results of NLO characteristics showed that the subject compounds are excellent candidates as NLO materials. The enhancement of NLO properties can be qualitatively explained by means of high charge transfer pattern. [ABSTRACT FROM AUTHOR]

• Preparation of some new mixed ligand complexes and their structural inspection • Geometry optimization for structural verification using DFT calculation • DNA interaction and biomedical evaluation of the prepared compounds • Molecular docking inspection for predicting of the biomedical evaluation The fabrication and structural identification of mixed ligand chelates resulting from 1-(1H-benzimidazol-2-yl) guanidine (BIG = main ligand) and 1,10-Phenanthroline (phen) (secondary ligand). The tested compounds were investigated using TGA, CHN, spectra analysis (FT-IR, Mass spectra, NMR), melting point, magnetic moments, molar conductance, Ultraviolet–Visible spectroscopy as well computational studies. The conductance results showed that the tested Pd(II), VO(II) and Ag(I) chelates have electrolytes in fresh solutions of DMSO lies in the range 38.12–118.87 Ω−1 cm2 mol−1 except, Cu(II) chelate is a non-electrolyte it is value equal 15.16 Ω−1 cm2 mol−1. FT-IR spectrum displays that the tested main ligand is coordinated with metal ions in a bi-dentate behavior with N, N donor sites of the HN=C and C=N. While the second ligand coordinated with metal ions through its N 2 atom in the pyridine ring. Moreover, the obtained analytical data regarding complexation in solution, molar ratio and continuous variation methods suggest 1M: 1 L molar ratio. Also the stability constant of tested complexes was identified in solution state and the formation constants (Kf) were evaluated by applying continuous-variation method. Stability of complexes was arranged by BIGPAg > BIGPVO > BIGPCu > BIGPPPd in agreement with K f values. The pH profile revealed that the wide range of pH stability of the tested complexes is at pH = 4- 10 in most of them. Magnetic and electronic spectra are applied to deduce the coordinating ability of the tested ligands and the geometric structure of the studied chelates. That data of magnetic susceptibility for ternary mixed chelates are locked to an octahedral geometry for Cu(II) & VO(II) chelates due to the data of (μeff = 1.8 and 1.83 B.M) respectively and Pd(II) and Ag(I) chelates are diamagnetic with square planar and tetrahedral geometry, respectively. The TGA study of these studied complexes displays that the hydrated H 2 O, acetate, nitrate, and acetylacetonate anions are removed in the first (45°C-180°C) and second degradation steps followed directly by degradation of the studied ligands in the following stages. The thermodynamic factors, like ΔS*, ΔH*, E*, A and ΔG* are evaluated from the TGA curves and explained. The DFT/B3LYP computation method was applied for the estimation of the MEP, (HUMO & LUMO) energy for the studied compounds. In-silico assay was executed by two different approaches over compounds to evaluate their biological behavior and degree of interaction with biological systems, before practical application. BIGPPd complex displayed priority in interaction with various protein. In-vitro assay was then carried out for compounds against different microbes and BIGPPd showed high antimicrobial activity with inhibition zones are established to be 45.75 ± 0.10 and 41.95 ± 0.05 mm against B. Cereus and G. Candidum at 25 µg/mL. Also, their cytotoxic behavior was examined against MCF-7, HepG2 and HCT-116 carcinoma cell lines, high cytotoxicity was clearly recorded with BIGPPd complex with IC 50 % are established to be (5, 6.25 and 7.14 µg/mL) respectively. Furthermore, antioxidant activity was examined, and the complexes exhibited high reactivity with trapping free radicals. The BIGPPd exhibited significant free radical scavenging activity with an IC 50 value of 20.15 μg/ml. The interaction of metal chelates with DNA was detected by gel electrophoreses, viscosity and spectral studies. Spectrophotometric titration and viscosity studies expose that each of tested complex is an avid binder to DNA. The intrinsic binding constants were calculated for all the tested compounds could bind to Ct-DNA generally through replacement, intercalative mode & minor groove binding of interactions with the sequence: BIGPVO (6.05×104) > BIGPCu > BIGPPd> BIGPAg >BIG (1.16×103). This may be due to enhanced hydrophobic & electrostatic interaction of aromatic rings. Finally, such complexes may be considered as a promising bioactive agent. [Display omitted] [ABSTRACT FROM AUTHOR]

• New mixed ligand complexes of Cr(III) (C1) & Fe(III) (C2) were synthesized and characterized. • The isolated complexes exhibited a ratio of 1:1:1 (M: MB: PDC). • The C1 and C2 complexes displayed activity potential to the phenoxazinone synthase mimicking. • The observed complexes had a high turnover number (k cat), compared to previously reported ones, suggesting their potential activity to the catalytic function of phenoxazinone synthase. The current study included the synthesis and characterization of newly mixed ligand complexes of Cr(III) (C1) & Fe(III) (C2) incorporating 2,6-pyridinedicarboxylic acid (PDC) and 2-methyl-1H-benzimidazole (MB). The isolated complexes exhibited a ratio of 1:1:1 (M:MB:PDC), indicating the existence of an octahedral configuration centered on the Cr(III) and Fe(III) core, as denoted by the chemical formula [M(MB)(PDC)(Cl)(H 2 O)]. The determination of the most stable coordination modes, trans/cis orientations of the water/chloride ligands, was achieved using theoretical calculations employing density functional theory (DFT). The purpose of these computations was the investigation of the two different trans/cis orientations of the water/chloride around the Cr(III)/Fe(III) center. The complexes were analyzed using DFT to optimize their geometrical properties, characterize their molecular orbitals, and determine the energies associated with the trans/cis coordination approaches of water/chloride around the Cr(III)/Fe(III) center. The trans-water/chloride around the Cr(III)/Fe(III) was found to be the most preferred coordination mode. The C1 and C2 complexes displayed activity potential to the phenoxazinone synthase mimicking through the aerial coupling of o-aminophenol (OAPh) to phenoxazine-2-one (phenox). The Michaelis-Menten enzymatic kinetics was used for the quantification of the mimicking activity. Various enzyme kinetics plots were used to measure a range of kinetic characteristics, such as the specificity constant and turnover number (k cat), as part of comprehensive evaluations of the catalytic cycles. The observed complexes had a high turnover number (k cat), compared to previously reported ones, suggesting their potential activity to the catalytic function of phenoxazinone synthase. [Display omitted] [ABSTRACT FROM AUTHOR]

• Novel Co(II) (C1), Ni(II) (C2), & Cu(II) (C3) mixed-ligand complexes have been synthesized. • Their antibacterial, antifungal & anti-inflammatory efficacy have been the focus of recent studies. • The C1, C2, and C3 complexes were found to be more potential anti-inflammatory candidates than the free ligands. • DFT & molecular docking results were correlated with in vitro activities & debated. Here, we combine the simple and readily synthesized azo-ligand [1-((4-Hydroxyphenyl)azo)-2-naphthalenol (PNP)] with 8-hydroxyquinoline (QPH) to develop and synthesize novel Co(II) (C1), Ni(II) (C2), and Cu(II) (C3) complexes. Their antibacterial, antifungal, and anti-inflammatory efficacy had been the focus of recent studies. This objective was reached by first synthesizing and characterizing novel C1, C2, and C3 complexes using elemental analysis, mass spectra, Fourier-transform infrared, electronic spectra, magnetic, Thermal, and molar ratio analysis. Octahedral structures were identified for the C1, C2, and C3 complexes. Quantum chemical characteristics and an optimized molecular structure for each substance were calculated using Density Functional Theory (DFT). To find out whether these substances are efficient in stopping the diffusion of dangerous microorganisms that are the most popular environmental pollutants, a disc diffusion check was carried out. All complexes demonstrated significantly larger inhibition zones (IZ) against both Gram-negative and Gram-positive bacteria compared to free ligands, with increases ranging from 70 % to 134 %. Against fungal strains, C2 and C3 showed the most significant enhancements, exhibiting up to 202 % increase in IZ compared to QPH and PNP. All complexes displayed reductions in minimum inhibitory concentration (MIC) compared to the free ligands against both bacteria and fungi. The most notable reductions were observed against Gram-negative bacteria, with complexes C1-C3 achieving up to 50 % reduction in MIC compared to QPH and PNP. Against fungal strains, complexes C2 and C3 generally showed better activity, with up to a 25 % reduction in MIC compared to the free ligands. Furthermore, the Egg albumin denaturation technique was studied to assess the anti-inflammatory activity. At a concentration of 10 %, C3 exhibited the highest activity at 83.26 %. As the concentration increased to 50 %, C3 maintained its superiority at 83.42%, followed closely by C2 at 78.39 %. At 100 %, C3 again displayed the highest activity at 84.13 %, while C2 and C1 showed comparable activity. Remarkably, at higher concentrations (250 % and 500 %), C3 consistently outperformed all other compounds, reaching an impressive antioxidant activity of 86.29 % at 250 % concentration. The antibacterial, antifungal, and anti-inflammatory activity was assisted by molecular docking investigation against 5JQ9 and 6CLV from Escherichia coli and Staphylococcus aureus , and COX-2 (5IKT) as anti-inflammatory target enzyme, which confirms the bioactivity behavior. In the interaction with 5JQ9, 6CLV, and 5IKT, C3 displayed strong H-donor and ionic interaction with (GLY42 and ASP85), (GLY42 and ASP85) and (CYS41 and GLY45). Notably, C3 consistently exhibited strong interactions across all three receptors, emphasizing its potential as an effective compound. These quantitative results provide valuable insights into the molecular interactions and binding affinities, supporting the bioactivity behavior observed in the experimental assays. In the end, DFT and molecular docking results were correlated with in vitro activities and debated. [Display omitted] [ABSTRACT FROM AUTHOR]

The exploration encompassed the synthesis and characterization of two innovative complexes, namely FePHNS and CuPHNS, employing a diverse array of analytical techniques such as elemental analysis, infrared and ultraviolet-visible spectroscopy, mass spectrometry, molar conductivity measurements, magnetic susceptibility assessments, and thermal analysis (TGA). In the spectral domain, infrared spectroscopy substantiated the tridentate ONS coordination of the PHNS ligand to the central metal atom. Thermal analysis offered valuable insights into the distribution and content of water molecules within the complexes. Density functional theory (DFT) calculations were harnessed to validate the molecular structures of both the PHNS ligand and its complex entities, providing an intricate comprehension of their quantum chemical parameters. The investigation extended to an evaluation of the in vitro antibacterial, antifungal, and antioxidant efficacy of the PHNS ligand and its complexes, revealing heightened biological activities for the complexes in comparison to the free PHNS ligand, notably with the CuPHNS complex demonstrating the highest activity, while the PHNS ligand exhibited the lowest. To delve into potential physiological activities, molecular docking studies were conducted, predicting the binding affinity of the compounds to proteins 2vf5 (Glucosamine-6-phosphate synthase in complex with glucosamine-6-phosphate) from Escherichia coli, 3cku (rate oxidase from Aspergillus flavus complexed with its inhibitor 8-azaxanthin and chloride) from Aspergillus flavus, and 5IJT (Crystal structure of Human Peroxiredoxin 2 Oxidized). The ensuing analysis of protein-ligand interactions and binding energies underscored the promising physiological activities of the investigated compounds, warranting further exploration for their potential in novel drug development. [Display omitted] • Novel Fe(III) and Cu(II) ions in molar ratios of 1:1 and 1:2 with PHNS ligand complexes have been synthesized. • Their in vitro antibacterial, antifungal, and antioxidant efficacy of the PHNS ligand and its complexes has been investigated. • The CuPHNS complex demonstrated the highest biological activity, while the PHNS ligand exhibited the lowest. • DFT and molecular docking results were correlated with in vitro activities [ABSTRACT FROM AUTHOR]

• Three distinct FeHNANSA, NiHNANSA, and CuHNANSA have been prepared & characterized via a wide variety of analytical methods. • In vitro experiments were conducted to evaluate the antibacterial, antifungal, anti-inflammatory, and antioxidant properties of the prepared compounds. • The metal complexes have heightened biological efficacy as compared to the free HNANSA ligand. • The findings obtained from docking experiments indicate that these compounds may possess a physiological function. Three novel metal complexes of 2‑hydroxy-1-naphthaldehyde azine (HNANSA) with iron(III), nickel(II), and copper(II) have been synthesized and characterized. Various analytical methods, such as elemental analysis, infrared spectroscopy, mass spectrometry, ultraviolet–visible spectroscopy, conductivity, magnetic testing, and thermal analysis, have been used to determine the structural and physical properties of the HNANSA and its metal complexes. The results indicated that; the HNANSA acts as a monobasic bi-dentate NO donor ligand and that the metal complexes contain water molecules in different patterns. Also, density functional theory (DFT) calculations have been performed to confirm the molecular structures and to study the quantum chemical parameters of the HNANSA and its metal complexes. Furthermore, the antibacterial, antifungal, anti-inflammatory, and antioxidant activities of the HNANSA and its metal complexes have been in vitro evaluated. The findings revealed that; the metal complexes have higher bioactivty than the free HNANSA ligand. Furthermore, molecular docking analyses have been performed against 2VF5 (Escherichia coli), 3CKU (Aspergillus flavus), 5IKT (Human Cyclooxygenase-2), and 5IJT (human peroxiredoxin 2), to estimate the binding affinities and interactions of the HNANSA and its metal complexes with target proteins. The results suggest that the HNANSA and its metal complexes may have potential applications in the development of new therapeutic agents. [Display omitted] [ABSTRACT FROM AUTHOR]

Herien, three new Fe(III) (FeAZD), Ni(II) (NiAZD), and Cu(II) (CuAZD) complexes were synthesized and characterized using various physicochemical and spectroscopic approaches. The H 2 AZD ligand acted as a bi-basic bi-dentate NO ligand in a 1:1 molar ratio. The results revealed that the FeAZD and CuAZD complexes had octahedral geometry, while the NiAZD had a tetrahedral geometry. The optimized geometry, HOMO and LUMO analysis of the ligand and its metal complexes was determined via Density functional theory (DFT) using the B3LYP with 6–311 G(d,p), and LanL2DZ level of theory. The FeAZD, NiAZD and CuAZD had lower energy gap, 7.40, 7.93 and 7.06 eV, respectively, than the free ligand (9.58 eV), which proposed that CuAZD was more active one. The free ligand and its metal complexes were in vitro investigated for their antibacterial and antifungal activity. The results illustrated that the metal complexes had higher antibacterial and antifungal activity than the free ligand. More specifically, the CuAZD demonstrated good antibacterial activity against E. coli , P. aeruginosa , S. aureus, B. cereus , and A. flavus , T. rubrum , and C. albicans , with activity indexes of 72.22%, 65.01%, 77.78%, and 72.22%, 63.16%, 59.09%, and 61.90%, respectively. Also, the metal complexes showed lower MIC (6.25–3.125 ppm) compared to the free ligand (about 50 ppm). Finally, molecular docking was utilized to investigate the ability of the free ligand and its metal complexes to inhibit the growth of E. coli (PDB ID: 5iq9). The results showed that the CuAZD had the highest binding affinity to the receptor, with a more negative docking score of − 7.05 Kcal/mol, and lower inhibition constant (Ki) of 6.90 µM. That is indicating that it may be the most effective at inhibiting the growth of E. coli (PDB ID: 5iq9). [Display omitted] • Three FeAZD, NiAZD, and CuAZD complexes were synthesized and characterized. • The complexes had a more promising antimicrobial than the free ligand. • High ability of metal complexes to inhibit the growth of E. coli (PDB ID: 5iq9). • Positive results proposed various medicinal purposes for these compounds. [ABSTRACT FROM AUTHOR]

• Square planar complexes of Ni2+, Pd2+ and Pt2+ with thiosemicarbazone (SNO) ligand. • DMSO coordinate via S to Pd(II) and Pt(II) complexes and X-ray crystal structure. • 3D geometry optimization was investigated using DFT approach. • Molecular docking against tyrosine kinase domain of the EGFR (1M17) was performed. • Cytotoxicity against Hela cancer and normal endothelial human cell lines (Eahy926). The ligand H 2 L with SNO sites and DMSO coordinated to Pd(II) and Pt(II) form square planar [PdL.dmso] and [PtL.dmso] complexes, whereas the Na[NiL.OAc] form with same ligand and CH 3 COO−. FTIR, UV-Vis, and 1H and 13C NMR spectroscopy and micro and physical analysis were used to characterize the compounds. The structures of [PdL.dmso] and [PtL.dmso] complexes were completely elucidated with single crystal X-ray diffraction analysis. The 6–311 G (d, p) and LANL2DZ basis sets of density functional theory (DFT) with the B3LYP approach were utilized to determine the optimal molecular geometries of compounds as well as the HOMO-LUMO energies and other metrics. The [PdL.dmso] showed the highest activity among all the compounds, with an IC 50 of 15.6 µM and a selectivity index (SI) of 2.8 against Hela. The complexes Na[NiL.OAc] and [PtL.dmso] exhibited significant activity against Hela with IC 50 of 105.7 µM and IC 50 of 166 µM respectively, whereas the ligand showed very poor activity. The complexes [PdL.dmso], [PtL.dmso] and ligand, H 2 L exhibited moderate activity against normal Eahy926 with IC 50 values of 43.3 µM, 45 µM, and 185 µM, respectively whereas, the Na[NiL.OAc] showed the highest cytotoxicity with an IC 50 of 5.8 µM. The complexes showed higher activity than free ligand due to the lipophilicity of the chelate. The group 10 metal complexes could be the promising cancer therapeutic agents. The lowest binding energy of -8.16 kcal/mol among all the tested compounds was found for [PdL.dmso] using molecular docking of active site crystal structure of the tyrosine kinase domain of the EGFR (PDB: 1M17). [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] A new Schiff-base ligand, 4-[(4-oxo-4,5-dihydro-1,3-thiazol-2-yl)hydrazono]methylphenyl 4-methylbenzenesulfonate (L), and its Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized and characterized. Elemental analysis, NMR spectroscopy, mass spectra, FT-IR analysis, molar conductivity, magnetic susceptibility tests and electronic spectra (UV-vis.) were all used to describe the ligand and its metal complexes. The complexes of Ni(II) and Zn(II) were found to have a tetrahedral structure, whereas those of Fe(III), Co(II) and Cu(II) exhibited an octahedral structure. The geometry of the ligand and its metal complexes was investigated by density functional theory (DFT) calculations at the B3LYP/6-311G(d, p) and LanL2dz levels of theory, respectively. To round out the picture, we evaluated not only the overall energy but also the HOMO and LUMO molecular orbitals and the molecular electrostatic potential (MEP). The synthetic analogues were tested for their in vitro antibacterial and antifungal efficacy against various pathogens using the disc diffusion method. The research shows that the metal complexes are more effective against these diseases than the free ligand. In addition, the DPPH method was used to measure the antioxidant activity in vitro. The antioxidant activity of each complex was higher than that of its free corresponding ligand. Molecular docking was carried out to determine the interactions between the complexes and the probable binding sites of Human Peroxiredoxin 2 Oxidized (PDB ID: 5IJT) and Escherichia coli (PDB ID: 3t88) receptors. [ABSTRACT FROM AUTHOR]

• Novel VO(II), Mn(II), Fe(III), Zn(II), and Ag(I)-benzenesulfonamide complexes have been synthesized. • The metal complexes have enhanced biological activity against their target microorganisms compared to the unbound ligand. • In vitro research was also conducted on the anti-inflammatory effects of the aforementioned substances. • The prepared compounds have physiological effects and might have broad use in the pharmaceutical industry. In this work, we synthesized and studied novel VO(II), Mn(II), Fe(III), Zn(II), and Ag(I) − 4-((2-hydroxy-1-naphthyl)azo) benzenesulfonamide complexes. Characterization techniques such as thermogravimetry (T.G.A), magnetic susceptibility testing, electrical conductivity studies, infrared spectroscopy, and mass spectroscopy all played crucial roles. Metal ions are coordinated by the azo Nitrogen (N N) and the hydroxyl Oxygen (–OH), as seen by the infrared spectra (IR). Our investigation of water's distribution and thermal behavior, in addition to its overall number, was made possible by techniques from thermogravimetry (T.G.A). The theoretical optimization of ligand (HL) and its metal complexes' molecular structures was accomplished by the use of density functional theory (DFT). Other quantum chemical properties might potentially be derived by using the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energy levels. In vitro testing was performed on both the ligand and its complexes to see whether or not they were capable of inhibiting the growth of harmful bacteria and fungi. The metal complexes have enhanced biological activity against the target microorganisms compared to the unbound ligand. In vitro research was also conducted on the anti-inflammatory effects of the aforementioned substances. Surprisingly, the AgL complex was the least active of the compounds tested, while the FeL complex was the most active. Based on molecular docking studies, we hypothesized that the synthesized compounds would bind to the cyclooxygenase-2 (COX-2) enzyme (Protein Data Base (PDB) ID: 5IKT) and the E. coli DNA gyrase B receptor (PDB ID: 1KNZ). Binding energies were calculated after studying protein-substrate interactions in depth. The molecular docking indications are that these compounds have physiological effects and might have broad use in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of new-(((9H-purin-6-yl)imino)methyl)-4-bromophenol complexes and their structural elucidation. • Geometry optimization for structural verification utilizing DFT calculation. • Biomedical applications against pathogens, free radicals and carcinoma cell lines. • Molecular docking studies for confirmation of pharmaceutical applications. Coordination compounds of Ag(I), Cu(II), Ni(II), Fe(III) and VO (II) ions were synthesized from the ligand 2-(((9H-purin-6-yl)imino)methyl)-4-bromophenol (ABS). Microanalysis, magnetic susceptibility, infrared spectroscopy, Ʌ m calculation, and thermal analysis were utilized to inspect the structure of the investigated complexes. As per the data collected, the constitution of the 1:1 cation–adenine imine ligand was found for ABSVO, ABSNi, ABSCu, ABSAg and 1:2 for ABSFe complex. The structural formula for the examined compounds was refined using DFT simulations. The DFT/B3LYP approach was used to calculate the energy gaps and other critical theoretical factors. Moreover, the experimental behavior of the described molecules towards Escherichia coli's glucosamine-6-phosphate synthase (PDB ID: 2vf5), Aspergillus flavus' urate oxidase (PDB ID: 3cku), and the breast cancer oxidoreductase receptor site was rationalized using molecular docking (PDB ID: 3HB5). The hydrogen bonding energies of docked specific receptors were estimated and examined. Furthermore, the inspected metal chelates were subjected to in vitro antibacterial, antifungal, antioxidant and cytotoxicity studies. ABSCu complex showed significant cell growth inhibition activity (IC50 = 5.04 ± 0.07 µg/mL), even higher than the standard anticancer drugs; cisplatin (IC50 = 5.71 ± 0.55 µg/mL) versus breast carcinoma cells. [ABSTRACT FROM AUTHOR]