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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]

Objective: The objective of this study was to investigate the 3D geometry optimization, theoretical spectroscopic features, chemical reactivity, antimicrobial activity, and inhibitory potential of two azo-coumarine derivatives, namely 6-[(E)-(4-hydroxy-2,5-dinitrophenyl)diazenyl]-2H-chromen-2-one (L1) and 6-[(E)-(10hydroxy-9-anthryl)diazenyl]-2H-chromen-2-one (L2). Methods: The 3D geometry optimization of the compounds was conducted using density functional theory (DFT) at the B3LYP/6-311G (d,p) level of theory. Theoretical infrared (IR) and UV-Vis spectral features were computed and compared with experimental values to validate the theoretical approach. Chemical reactivity was assessed based on electronic chemical descriptors such as energy gap (ΔE), electronegativity (χ), electronic chemical potential (μ), global chemical hardness (η), global softness (σ), global electrophilicity index (ω), and nucleophilicity index (Nu). The antimicrobial activity of the compounds was evaluated against pathogenic bacteria and fungi using the disc diffusion method. Molecular docking studies were performed to investigate the inhibitory potential of the compounds against receptors associated with breast cancer (PDB ID: 3I89), hepatitis C virus (HCV; PDB ID: 5TRH), hepatitis B virus (HBV; PDB ID: 5T2P), and hepatitis A virus (HAV; PDB ID: 5WTG). Results and Discussion: The study revealed good agreement between the experimental and theoretical spectroscopic data, indicating the reliability of the computational approach. The electronic chemical descriptors suggested the chemical reactivity and stability of the compounds, with lower energy gap (ΔE) values indicating higher reactivity. The antimicrobial screening showed promising results, with the compounds exhibiting significant antimicrobial activity against both Gram-positive and Gram-negative bacteria as well as fungi, as evidenced by their lower MIC values. Molecular docking simulations suggested that the studied compounds have the potential to act as inhibitors against the receptors associated with breast cancer and various hepatitis viruses, highlighting their possible utility in antiviral and anticancer treatment strategies. Conclusions: In conclusion, the azo-coumarine derivatives (L1) and (L2) demonstrated favorable theoretical and experimental characteristics, including structural optimization, spectroscopic features, chemical reactivity, antimicrobial activity, and inhibitory potential against viral receptors. These findings suggest that (L1) and (L2) hold promise as potential candidates for further development as antimicrobial and antiviral agents, as well as for their potential application in cancer therapeutics. [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]

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has caused a global health crisis. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly contagious virus that can cause severe respiratory illness. There is no specific treatment for COVID-19, and the development of new drugs is urgently needed. Problem statement: The SARS-CoV-2 main protease (Mpro) enzyme is a critical viral enzyme that plays a vital role in viral replication. The inhibition of Mpro enzyme can be an effective strategy for developing new COVID-19 drugs. Methodology: An efficient operationally simple and convenient green synthesis method had been done towards a series of novel spiro-N-(4-sulfamoylphenyl)-2-carboxamide derivatives, in ethanol at room temperature in green conditions, up to 90% yield. The molecular structures of the synthesized compounds were verified using spectroscopic methods.The title compounds were subjected to in silico analysis, including Lipinski's rule and ADMET prediction, in addition to pharmacophore modeling and molecular docking against the active site of SARS-CoV-2 target main protease (Mpro) enzyme (6LU7). Furthermore, both of the top-ranked compounds (5 and 6) and the standard Nirmatrelvir were subjected to DFT analysis. Findings: The synthesized compounds exhibited good binding affinity to SARS-CoV-2 Mpro enzyme, with binding energy scores ranging from − 7.33 kcal/mol (compound 6) and − 7.22kcal/mol (compound 5) to − 6.54 kcal/mol (compounds 8 and 9). The top-ranked compounds (5 and 6) had lower HOMO–LUMO energy difference (ΔE) than the standard drug Nirmatrelvir. This highlights the potential and relevance of charge transfer at the molecular level. Recommendation: These findings suggest that the synthesized spiro-N-(4-sulfamoylphenyl)-2-carboxamide derivatives could be potential candidates for COVID-19 drug development. To confirm these drugs' antiviral efficacy in vivo, more research is required. With very little possibility of failure, this proven method could aid in the search for the SARS-CoV-2 pandemic's desperately needed medications. [ABSTRACT FROM AUTHOR]

In the pursuit of tracking some physicochemical properties of fluids down to the molecular level, ab initio molecular surface analyses were performed on 169 molecules. This included electrostatic potential (EP), average local ionization energy (ALIE), and electron localization function (ELF) mapped onto an electron density isosurface value of 0.001 au. Using stepwise linear regression (SLR) analysis, it was found that besides the well-studied EP, ALIE and ELF played important roles in determining the normal boiling and freezing points and critical temperatures of fluids. Apparently, the ALIE and ELF were relevant to the attractive polarization forces and repulsive Pauli forces, respectively, between molecules. To further demonstrate and rationalize this assumption, a localized molecular orbital energy decomposition analysis (LMO-EDA) was carried out. In the LMO-EDA analysis, the complexes of the helium atom, He, and ClCl, ClBr, ClI, OCO, OCS, OCSe, and CO/OC molecules were investigated, where the helium atom faced different molecular sites in each molecule. Fortunately, the results showed that lower the ALIE value on a molecular site, the stronger (i.e., more attractive) the polarization interaction energy. The results also indicated that higher the ELF value on a molecular site, the stronger (i.e., more repulsive) the Pauli interaction. The work is aimed to present novel molecular-based rationales to physical chemists, chemical engineers, and materials scientists. [ABSTRACT FROM AUTHOR]

2-Guanidinobenzimidazole (BIG) and Imidiazole (I) ligands were utilized to synthesize Cu(II), VO(II), Ag(I), and Pd(II) as mixed ligand complexes. All studied molecules were characterized through various spectral, analytical and computational studies to find out their chemical structure. TGA was applied to identify the occurrence of H2O molecules besides the mono-nuclear property of isolated complexes. These complexes were proved through DFT study to confirm the coordinating site that was proposed and displays the optimal three-dimensional structures of the studied compounds. The binding affinity of the tested complexes with CT-DNA has been tested through agarose gel, electronic spectroscopy and viscosity measurements. Furthermore, the studied molecules might bind to CT-DNA electrostatically through exterior contact, replacement, intercalation and groove surface binding with good affinity. In-vitro anti-bacterial, anti-fungi, cytotoxic and antioxidant activities are performed for all studied compounds. MOE-docking simulation results indicate promising inhibitory features of BIGIPd complexes, in agreement with in-vitro results. [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 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 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]

Herein we report the synthesis of organic selenide-based maleanilic and succinanilic acids in good yields (up to 95%). Their structural identities were elucidated by spectroscopic techniques (e.g., IR, 1H- & 13C-NMR, and MS). The ADMET analysis, molecule electrostatic potential map, DFT, and frontier molecular orbital were used to study the organoselenium compounds' pharmacokinetics, drug-likeness characteristics, geometries, and chemical and electronic properties. Moreover, a molecular docking tool was employed to investigate the organic selenides' ability to inhibit the SARS-CoV-2 Mpro target (PDB: 7BFB). Within this context, organic selenides exhibited promising binding affinities to the SARS-CoV-2 Mpro receptor in the following order (12 > 11 > 10 > 9 > 7 > 8). Furthermore, molecular dynamics simulations were also carried out for 200 ns to evaluate the exact behavior of the most active compound (12) within the Mpro binding pocket of SARS-CoV-2 compared with its co-crystallized inhibitor (Co). [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]

In this study, 2-[(carbamothioylhydrazono)methyl-phenyl-4-methylbenzenesulfonate (CHMPMBS), which exhibits selective colorimetric chemosensor properties for Cu(II) ions, was synthesized and characterized by NMR and FT-IR spectroscopy. The CHMPMBS chemosensor demonstrated high sensitivity and selectivity toward Cu(II) in an aqueous media in the presence of many other competing cations (Na(I), Mg(II), Al(III), K(I), Ca(II), Cr(III), Mn(II), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Sr(II), Ag(I), Cd(II), Ba(II), and Pb(II). By forming a complex of 1: 1 stoichiometry (Cu: CHMPMBS) with Cu(II), the developed chemosensor gave a distinctive color change from pale yellow to pale green. CHMPMBS exhibits a rapid and accurate colorimetric assay for naked-eye detection of Cu(II) ions with a detection limit of 8.12 µM. Furthermore, the potential application of CHMPMBS has been extended to detect Cu(II) ions with functional recovery in both natural and simulated water samples. Furthermore, the Cu(II)-CHMPMBS complex was synthesized and characterized. The thermodynamic (ΔG, ΔH, and ΔS) and kinetic (Ea) parameters were investigated at four temperatures. Further, the binding constant of CHMPMBS, which binds to Cu(II) ions according to 1:1 stoichiometry, was determined to be 2.47 × 104 M−1. [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]

A new heterocyclic azo dye ligand (L) was synthesized by the combination of 4-amino antipyrine with 4-aminophenol. The new Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) complexes were synthesized in excellent yields. The metal chelate structures were elucidated using elemental analyses, FT-IR, 1H-NMR, mass, magnetic moment, diffused reflectance spectral and thermal analysis (TG-DTG), and molar conductivity measurement. According to the FT-IR study, the azo dye ligand exhibited neutral tri-dentate behavior, binding to the metal ions with the azo N, carbonyl O, and protonated phenolic OH. The 1H-NMR spectral study of the Zn(II) complex supported the coordination of the zo dye ligand without proton displacement of the phenolic OH. Diffused reflectance and magnetic moment studies revealed the octahedral geometry of the complexes, as well as their good electrolytic nature, excepting the Zn(II) and Cd(II) complexes, which were nonelectrolytes, as deduced from the molar conductivity study. The theoretical calculations of optimized HOMO–LUMO energies, geometrical parameters, electronic spectra, natural atomic charges, 3D-plots of MEP, and vibrational wavenumbers were computed and elucidated using LANL2DZ and 6-311G (d, p) basis sets of density functional theory (DFT) with the approach of B3LYP DFT and TD-DFT methods. The ligand and complexes have been assayed for their antimicrobial activity and compared with the standard drugs. Most of the complexes have manifested excellent antimicrobial activity against various microbial strains. A molecular docking investigation was also performed, to acquire more information about the binding mode and energy of the ligand and its metal complexes to the Escherichia coli receptor using molecular docking. Altogether, the newly created ligand and complexes showed positive antibacterial effects and are worth future study. [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]

The characteristics of isotropic etching of silicon in a purely inductively coupled SF 6 plasma are quantitatively studied. Since the etch results are strongly dependent on mask features, the authors investigated both large area and narrow trench etch characteristics. Circles of diameter 500 μ m were used as a proxy for unpatterned surfaces and etched for different durations to establish the material etch rate and surface roughness. The average etch rate using the chosen recipe was found to be 2.27 μ m/min. Arrays of narrow trenches ranging from 8 to 28 μ m were also etched to analyze the effect of trench size on etch rate and degree of anisotropy. The etch rate of the trenches was found to strongly decrease with decreasing trench width. The results demonstrate that isotropic SF 6 etch can be readily used as a replacement for more exotic silicon vapor phase etch chemistries such as XeF 2. [ABSTRACT FROM AUTHOR]