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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 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]

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]

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]

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]

• 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]

• Two new series of N -4 piperazinyl sulfur containing Ketene S,S -acetals and Ketene N,S -acetals, based norfloxacin analogues had been synthesized and characterized. • The synthesized compounds had been evaluated against pathogenic fungi and Gram-positive/Gram-negative bacteria. • Synthetic compounds demonstrated comparable efficacy to norfloxacin against tested bacteria, with MIC values ranging from 1.56 to 50 µg/ml. • Compounds 8, 9 , and 10 displayed potent antifungal activities, surpassing Griseofulvin. • Molecular docking studies revealed diverse binding of target compounds with 1HNJ protein from E. coli , indicating potential as 1HNJ-targeting agents. • Density functional theory analysis for 8, 9 , and 10 , along with norfloxacin, showed comparable HOMO-LUMO energy differences, softness, and hardness, highlighting the significance of charge transfer at the molecular level. The in vitro antimicrobial activity was investigated for two new series of N -4 piperazinyl sulfur containing Ketene S,S-acetals and Ketene N,S-acetals, based norfloxacin analogues against two pathogenic fungi and four pathogenic Gram-positive and Gram-negative bacterial strains. The majority of synthetic compounds exhibit comparable efficacy to norfloxacin against the four tested bacteria. The MIC of the compounds varied from 1.56 to 50 µg/ml. Compounds 8, 9 , and 10 exhibited good antifungal activities compared to Griseofulvin. Most of the tested compounds showed promising antibacterial activity. Compounds 4, 9 and 10 showed twice the activity against E. coli (MIC = 3.12 µg/ml), while 6 showed twice the activity against P. aeruginosa (MIC = 6.25 µg/ml), compared to norfloxacin. Similarly, 5 and 9 showed double the activity against k. pneumonia (MIC = 3.12 µg/ml) and 3 showed higher activity against the Gram positive S. aureus. Compounds 1–10 underwent a comprehensive molecular docking investigation with 1HNJ protein from E. coli and showed diverse binding. The binding affinities, expressed as docking scores (S, kcal/mol), exhibited a range from −8.67 (9), −8.47 (10), and −8.45 (8), to −6.85 (7), and −6.47 (3) Kcal/mol. The outcomes of this investigation provide compelling evidence for the inhibitory potential of these compounds against 1HNJ, suggesting a new 1HNJ-targeting agents. Results of Density Functional Theory analysis for 8, 9 and 10 and norfloxacin showed that the calculated HOMO-LUMO energy differences (Δ E), softness, and hardness for compounds 8, 9 and 10 were found to be comparable to that of norfloxacin, emphasizing the significance of charge transfer at the molecular level. [Display omitted] [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]

[Display omitted] • New Fe(III) (C1), Ni(II) (C2), and Cu(II) (C3) with the ligands moxifloxacin (MOX) and tri-substituted imidazole (TSI) complexes were synthesized and characterized. • The complexes were investigated in vitro for antibacterial efficacy against two gram-positive and two gram-negative bacteria. • The C1, C2, and C3 complexes have been proven to be more biologically effective than a ligand without the antibiotic MOX. • Compared to ascorbic acid, all newly synthesized compounds exhibit similar IC 50 values for free radical scavenging. Herein, three new mixed-ligand complexes were synthesized through the reaction of Fe(III), Ni(II) and Cu(II) with moxifloxacin (MOX) in the presence of tri-substituted imidazole (TSI) to investigate their antibacterial, antifungal, and antioxidant potential. Elemental analysis, molar conductivity, electronic spectra, infrared spectroscopy, mass spectrometry, magnetic studies, thermal gravimetric investigations have been utilized for insuring the chelation process and structural elucidation. Results revealed that MOX and TSI interact with the metal ions via the (carbonyl oxygen and the carboxylic oxygen) and (hydroxyl oxygen and imidazole-ring nitrogen) atoms for MOX, and TSI, respectively. Octahedral geometries have been proposed for the Fe(III), Ni(II) complexes, while a distorted tetrahedral geometry was proposed for the Cu(II) complex. The proposed structures had been optimized via Density functional theory (DFT) calculations. Moreover, the frontier molecular orbitals (FMOs), in terms of HOMO and LUMO, and the molecular electrostatic potential (MEP) were obtained. Furthermore, the energy gap, chemical hardness, softness, chemical potential, electrophilicity index were evaluated. The antimicrobial potential was in vitro investigated against some common pathogenic bacterial and fungal strains; moreover, the antioxidant activity was evaluated using DPPH method. Results revealed that the three synthesized complexes had high antimicrobial activity against all tested phytopathogens and a significant antioxidant potential, compared to the free ligands. Furthermore, the in vitro potential was validated utilizing molecular docking investigation against four target receptors: 5JQ9, 6CLV, 3CKU, and 5IJT. The molecular docking results showed that Fe(III), Ni(II), and Cu(II) complexes had the highest activity towards the 5JQ9, (6CLV and the 3cku), and 5IJT receptors, respectively. [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]

[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]

Some novel thieno[2,3-b]thiophene-2,5-dicarbonitrile derivatives namely; 3,4-bis(2-hydroxynaphthalen-1-yl)diazenyl)thieno[2,3-b]thiophene-2,5-dicarbonitrile, 3,4-bis(4-aminonaphthalen-1-yl)diazenyl)thieno[2,3-b]thiophene-2,5-dicarbonitrile and 3,4-bis(4-(dimethylamino)phenyl) diazenyl)thieno[2,3-b]thiophene-2,5-dicarbonitrile have been synthesized and characterized by FT-IR and NMR spectroscopies. Thin films of the synthesized thieno[2,3-b]thiophene-2,5-dicarbonitrile derivatives have been deposited by the thermal evaporation method and characterized by UV-VIS-NIR spectroscopy. Their spectral dependences of absorption, dielectric, dispersion and allied parameters have been investigated, discussed, and compared with published results. The high absorption coefficient (∼ 10 5 c m − 1) at a solar maximum wavelength (λ ≅ 500 n m) and the band and optical gap energies of 2.95 and 2.15 eV, respectively manifested by the present samples make them suitable to be applied in optoelectronic devices, especially as solar absorber material. The revealed high values of non-linear refractive index n 2 and 3rd order non-linear susceptibility revealed by these organic compound films, which are significantly higher than those of chalcogenide and oxide materials recommend them as promising NLO-elements. These results have been insured by geometry optimization and NLO calculations using Density Functional Theory with B3LYP method in the level of 6–311 G (d,p). [Display omitted] • Synthesizing and characterization of novel azo dye for the first time. • Their spectral dependences of absorption, dielectric, and dispersion parameters have been investigated. • The values of non-linear refractive index n 2 and 3rd order non-linear recommend them as promising NLO-elements. • The results have been insured using Density Functional Theory with B3LYP functional and 6–311 G (d,p) basis set. [ABSTRACT FROM AUTHOR]

• Synthesis and characterization of new Cu(II) mixed-ligand complexes based on Schiff base and N-heterocyclic ligands. • Chemical descriptors evaluation based on DFT calculations. • In-vitro screening the inhibitory capacity of the synthesized compounds against the growth of pathogenic bacteria and fungi. • The complexes exhibited high catalytic phenoxazinone synthase-like activity. • Deriving SAR model between practical biological/catalytic activity and calculated chemical descriptors. Three new Cu(II) mixed-ligand complexes of the type [Cu(primary ligand)(secondary co-ligand)], were synthesized, characterized and preliminary tested for their biochemical activities. The primary ligand (HL) was derived from condensation of p-toluidine with 2-hydroxy-naphthalhyde. Three different N-heterocyclic compounds, 8-hydroxy-quinoline (HQ), 2-(1H-benzimidazol-2-yl)phenol (HB), and 2‐(4,5‐diphenyl‐1H‐imidazol‐2‐yl)phenol (HI), were used as secondary co-ligands. Inhibitory capacity of the synthesized compounds were screened against the growth of pathogenic bacteria E. coli (G–) and B. cereus (G+)] and fungi (A. fumigatus), in terms of inhibition zone (IZ, mm), and minimum inhibitory concentration (MIC, μg/mL) using the disc diffusion method. Furthermore, the complexes were tested for their phenoxazinone synthase-like activity in terms of K cat. Density functional theory (DFT) calculations based on B3LYP with LanL2DZ level of theory were performed to prove the proposed geometry of the complexes as well as evaluate the electronic parameters responsible for their reactivity. Structure activity relationship formula was derived by correlating the experimental data (MIC or K cat) with the calculated electronic parameters. [ABSTRACT FROM AUTHOR]

• New Fe complexes based on Schiff-base & N-heterocyclic ring have been assembled. • DFT calculations were performed to estimate the electronic properties. • The complexes showed a promising antibacterial and antifungal activity. • Phenoxazinone synthase mimicking activity was explored. • Structure activity relationship (SAR) for these complexes had been derived. New Fe(III) complexes with mixed ligands based on 1-{(E)-[(4-methylphenyl)imino]methyl}-2-naphthol (HN) as primary ligand and secondary co-ligand of O-hydroxy quinolone (HQ), 2-(1H-benzimidazol-2-yl)phenol (HB) and 2-(4,5-diphenyl-1H-imidazol-2-yl)phenol (HI) had been isolated and characterized. The isolated complexes had 1:1:1 ratio for Fe(III):ligand:co-ligand with one chloride and one water molecule coordinated to the Fe-centre, suggesting octahedral structure around the Fe-center with the formula [Fe(Ligand)(co-ligand)(Cl)(H 2 O)]. Theoretical calculations using density functional theory by B3LYP with LANL2DZ basis set had been done for two possible orientations of the ligand moieties around the Fe-center, to find out the most reliable coordination modes. Calculations include geometry optimization, molecular orbital description, and energy evaluation of trans- and cis-coordination modes of the chloride and water around the Fe-center. In-vitro antibacterial and antifungal properties of the isolated complexes have also been examined against pathogenic bacteria, E. coli (G−), B. cereus (G+), and A. fumigatus fungi, by using broth microdilution and disc diffusion methods. The target compounds exhibited considerable growth inhibition against selected pathogenic microorganisms as antimicrobial candidates with low minimum inhibitory concentration (MIC). The complexes showed biomimetic phenoxazinone synthase-like activity for the aerial coupling oxidation of o-aminophenol (OAP) to phenoxazine-2-one (Phz), in acetonitrile (ACN) solution, with high turnover number (K cat). Structure Activity Relationship (SAR) model was derived, using Multi-Linear Regression analysis, by correlation the practical biological (MIC) data with calculated chemical descriptors. [ABSTRACT FROM AUTHOR]