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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 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 wide biological actions of triazolotriazine hybrids, benzene‐sulfonamide derivatives, exhibit a good chance of displaying in vitro anti‐inflammatory effects. An operationally simple one‐pot, three‐component, and convenient synthesis method is used toward the synthesis of a series of diverse 2‐(2‐(4‐amino)‐1,3,5‐triazaspiro‐1,4‐dien‐2‐yl) hydrazinyl)‐N‐(4‐sulfamoylphenyl)‐2‐thioxoacetamides, which generated via reaction of 2‐hydrazinyl‐N‐(4‐sulfamoylphenyl)‐2‐thioxoacetamide, cyanoguanidine, and cyclic/acyclic ketones and were characterized by spectral analysis (IR, Nuclear Magnetic Resonance: 1H‐NMR, 13C‐NMR, and elemental analysis). The spirotriazolotriazine derivatives are obtained with up to 95% yield, and their structure–activity relationship was discussed. All compounds were tested for in vitro anti‐inflammatory potential using the inhibition of RBC hemolysis technique and COX inhibition assay. The results from RBC hemolysis technique demonstrated that almost all evaluated compounds exhibited significant in vitro anti‐inflammatory efficacy. More specifically, compounds 7, 8, and 12 have superior membrane stability over indomethacin as a standard drug. At concentrations of 400, 600, 800, and 1000 μg/mL, compound 12 demonstrated highly significant inhibition of RBC hemolysis with 95.2%, 97.3%, 98.9%, and 99.8%, respectively, compared with indomethacin at the same concentrations (94.5%, 97.3%, 98.5%, and 99.3%, respectively). COX assay indicated that compounds 7, 8, and 12 exhibited excellent COX‐2 inhibition percentage (98.51 ± 0.01, 98 ± 0.01, and 98.97 ± 0.06, respectively) at 150 μg/mL using indomethacin (97.3 ± 0.005). Furthermore, an investigation using molecular docking against COX‐2 (pdb ID: 5IKT) was used to analyze the anti‐inflammatory properties of all studied substances. When compared to indomethacin, molecular docking research showed a strong connection with the intended protein and an elevated docking score. According to in vitro anti‐inflammatory action and computational approach, they show promise as a therapeutic candidate for the treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Three GUBZCu, GUBZVO, and GUBZPd chelates have been prepared from 2‐guanidino benzimidazole (GUBZ ligand) by a bidentate coordinating approach. FT‐IR, mass, and NMR spectra; magnetic moment; CHN analysis; UV–Vis spectra; molar conductance; and TGA were studied to describe and estimate the molecular formulae of tested molecules. The stability constant for GUBZ complexes was estimated in the solution. Also, the pH profile displays the extra stability of tested complexes. Structure elucidation of the studied complexes had been supported by density functional theory (DFT) along with calculated electronic and vibrational spectra. Electronic absorption spectra were estimated practically through UV–Vis spectra and theoretically performed using the time‐dependent TD‐DFT/B3LYP, for computing the absorption maximum, oscillator strength, and excitation energy of the tested compounds. This study was done into these chelates' catalytic performances for the environmentally friendly synthesis of 7‐amino‐4,5‐dihydro‐tetrazolo[1,5‐a]pyrimidine‐6‐carbonitrile derivatives utilizing aromatic aldehyde, malononitrile, and 5‐amino tetrazole as reactants. The used reactions have been directed in a concerned environment through a green solvent. The obtained results verified the promising catalytic activity and selectivity of the tested complexes. All tested reaction conditions have been enhanced between variable Lewis acid catalysts in associating to our studied complexes. GUBZPd catalyst presented an advantage in overall tests through high yield, green conditions, and short time. Also, the regaining of hetero‐catalyst has prospered as well as recycled through the same effectiveness up to four or five times, and then the performance has been reduced. The mechanism of action has been recommended depending on the capability of the Pd (II) complex for totaling extra bonds above the z‐axis as well as reinforced with theoretical study. This strategy's simplicity, safety, commercially accessible catalyst, stability, fast reaction time, and outstanding yields may be used in the industry in the future. [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]

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]

Novel compounds with pharmacological activity were synthesized from Pd (II), Fe (III), Cr (III), Ni (II), and Cu (II) ions with 4‐{2‐(3‐carboxy‐1‐cyclopropyl‐6‐fluoro‐7‐piperazin‐1‐yl‐2,3‐dihydro‐1H‐quinolin‐4‐ylideneamino)‐phenylimino}‐1‐cyclopropyl‐6‐fluoro‐7‐piperazin‐1‐yl‐1,4‐dihydro‐quinoline‐3‐carboxylic acid (CFPD). The newly synthesized compounds have been investigated by 1H‐ and 13C‐NMR spectra, Fourier transform infrared spectra, CHN analyses, ultraviolet‐visible spectra, mass spectra, molar conductivity, and magnetic moment measurements. In addition, the pH profile of the CFPD complexes showed remarkable stability, and their stability constant was identified in solution. To find out essential characteristics for CFPD and its complexes and to investigate the molecular geometry, computational analysis occurred. Through its nitrogen and OH of carboxylate groups, the ligand interacted with the metal ions to form CFPDPd complex with a square planar geometry and CFPDCu, CFPDCr, CFPDNi, and CFPDFe complexes with octahedral geometry. The M:L ratio of 1:1 was demonstrated by the molar ratio and sequence variation techniques’ outcomes. The effect of the investigated CFPD imine ligand on bacterial community and its metal chelate was examined within vitro using a range of fungal and viral pathogens The findings showed that the effectiveness of antimicrobial went with the directive: CFPDPd complex when compared to the highly suppressor complex, fluconazol and ofloxacin as model medication. The novel ligand’s and its complexes’ in vitro cytotoxic potential against the Hep‐G2, MCF‐7, and HCT‐116 cell lines was also studied. The findings once more indicated that, when compared to vinblastine medication, the CFPDPd chelate is the most active agent. In addition, the complexes showed high reactivity in catching free radicals when their antioxidant activity was examined. By the application of viscosity, spectrum analysis, and gel electrophoreses, the interaction among metal chelates and DNA was determined. Studies on viscosity and spectrophotometric titration showed that every substance in test is a strong DNA binder. Increased hydrophobic and electrostatic interactions between aromatic rings could be the cause of this. In conclusion, these complexes have the potential to be effective bioactive agents. [ABSTRACT FROM AUTHOR]

The reaction of the synthesized 2‐(4,5‐diphenyl‐1H‐imidazol‐2‐yl) phenol, (HL) ligand with FeIII, CoII, NiII, CuII, and ZnII ions at room temperature resulted in the formation of the five complexes; [Fe(L)2(H2O)(Cl)]·2H2O and [M(L)2)]·nH2O [M = Co, Zn (n = 2), Ni, Cu (n = 1)]. The ligand and its complexes were characterized based on elemental analyses, spectral, magnetic and molar conductance measurements. The molecular and electronic structure of the ligand and its complexes was optimized theoretically and the quantum chemical parameters were calculated. The results revealed an interesting geometrical variation; octahedral for FeL, seesaw for CoL, distorted square planar for NiL and CuL, as well a tetrahedral arrangement for ZnL. The HL ligand and its metal complexes were screened against the growth of pathogenic bacteria [Escherichia coli (G–) and Bacillus cereus (G+)] and fungi (Aspergillus fumigatus) in terms of the minimum inhibitory concentration (MIC). The metal complexes showed high enhancement as antimicrobial candidates with lower MIC values compared with their parent ligand. Structure activity relationship formula was quantified by correlating the experimental MIC values with theoretical electronic chemical properties. Molecular docking of the complexes against CYP51B protein of A. fumigatus, the target enzyme for the antimicrobial reagents, was achieved to find the best orientation of the substrate, which would form a stable complex with overall minimum energy. The docking results enhanced the activity of the imidazole‐based complexes as promising antimicrobial candidates. [ABSTRACT FROM AUTHOR]

ABSTRACT Novel compounds with pharmacological activity were synthesized from Pd(II), Fe(III), Cr(III), Ni(II), and Cu(II) ions with 1‐cyclopropyl‐6‐fluoro‐4‐(2‐hydroxy‐phenylimino)‐7‐piperazin‐1‐yl‐1,4‐dihydro‐quinoline‐3‐carboxylic acid (CFAP). The ligand's NH and OH groups allowed it to interact with the metals as a neutral tridentate. The investigated novel compounds were described using 1H and 13C NMR spectra, FT‐IR spectrums, TGA and UV–Vis (conductance of molecules), and CHN‐analysis. Additionally, the pH profile of the CFAP complexes indicated great stability, and the complexes' stability constant was discovered in the solution. To extract important properties for CFAP and its complexes, computational research was used, CFAPCu, CFAPCr, CFAPNi, and CFAPFe have octahedral geometry, while CFAPPd has square planar geometry. To investigate the molecular geometry, density functional theory calculations (DFT) were carried out. The molar ratio and continuous fluctuation data confirmed that the (M:L) ratio was (1:1). In vitro tests were conducted to evaluate Schiff base's antimicrobial action ligand and its metal chelates against fungal and bacterial infections. The findings showed that the antimicrobial efficacy is as follows: When CFAPPd is compared to fluconazol and ofloxacin as reference medications, it is the highly inhibitor complex. The novel CFAP ligand and its complexes were investigated for In vitro carcinogenic potential against Hep‐G2, MCF‐7, and HCT‐116 cell lines. As compared to the medication vinblastine, the results once again demonstrated that CFAPPd is the most active agent. Moreover, the complexes demnstrated strong reactivity in capturing free radicals when their antioxidant activity was investigated. Viscosity, spectral investigations, and gel electrophoreses were used to identify the interaction between metal chelates and DNA. Every examined compound is shown to be an enthusiastic DNA binder by viscosity and spectrophotometric titration investigations. The heightened hydrophobic and electrostatic interactions between aromatic rings could be the cause of this. Ultimately, these compounds could be regarded as promising bioactive substances. [ABSTRACT FROM AUTHOR]