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

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

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]