Search

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]

Metal complexes derived from Schiff bases are known to have a wide range of applications, spanning the areas of material and medicinal sciences. Herein, a Schiff base ligand, (Z)‐2‐(((4‐chlorophenyl)imino)methyl)naphthalen‐1‐ol HL, was synthesized via a condensation reaction between 2‐hydroxy‐1‐naphthaldehyde and 4‐chloroaniline using methanol as a solvent in the presence of a catalytic amount of formic acid. The obtained ligand was further reacted with Mn(II), Ni(II), and Cu(II) using their acetate salts in a 1 : 2 stoichiometric ratio of metal to ligand to afford complexes C1–C3, respectively. Physicochemical and analytical techniques consisting of FTIR, UV‐Vis, elemental (CHN and metal content), TGA, HRMS, 1H, and 13 C NMR spectroscopy were deployed to establish the formation of the compounds. Results show that the ligand coordinated with the metal ions through the oxygen and nitrogen atoms of the phenolate and azomethine moieties, respectively, forming ON‐type complexes. Furthermore, the free ligand and its complexes were evaluated for their antioxidant activity compared to the standard (ascorbic acid) using an in vitro DPPH radical scavenging assay. From this investigation, C1 demonstrated higher radical scavenging activity than the free ligand, the complexes, and the standard (ascorbic acid). But the ligand has better scavenging activity than C2 and C3 at higher concentrations. DFT was also used to examine the electronic properties of the compounds, and the data obtained corroborated well with the experimental study. [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]

Gelatin, resulting from collagen, a naturally occurring protein found in ligaments and tissues, is formed through the boiling of connective tissues, bones and animal skins, commonly sourced from cows. Its exceptional properties, including the ability to form strong, transparent gels and flexible films, easy digestibility, solubility in hot water and positive binding action, make gelatin a highly valuable resource in various industries such as food processing, pharmaceuticals, photography and paper production. It is regarded as non-toxic, biocompatible, biodegradable and generally safe for use. Gelatin serves as a key ingredient in the manufacturing of a wide range of products, with a notable example being hard gelatin capsules, which come in varying levels of solubility in water. In this study, a Schiff base was synthesized by modifying gelatin with salicylaldehyde in ethanol at room temperature, a mixture of gelatin-Schiff base added to appropriate copper chloride sonicated in ethanol, the mixture was poured onto glass plates and allowed to dry. Modified gelatin film was produced and characterized using FTIR spectroscopy, while its surface properties were examined through Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Furthermore, the modified gelatin film's potential biological activity was assessed against bacterial strains. The antibacterial screening tests revealed that the modified gelatin exhibited promising antibacterial activity against microorganisms, indicating an improvement in its antibacterial efficacy. These findings highlight the enhanced antibacterial potential of the modified gelatin film, further contributing to its versatility and potential applications in various fields. Different molecular weight distributions within the gelatin can lead to variations in film formation and subsequent surface features. Additionally, the composition of the gelatin film, including the presence of any crosslinking agents or modified functional groups, can further influence the resulting surface morphology. This study focuses on the preparation of modified gelatin films using suitable aldehyde compounds and explores their potential for pharmaceutical applications. Various techniques assessment of biological activity will be employed to investigate the properties and performance of the modified gelatin films. [ABSTRACT FROM AUTHOR]

The current work reports the synthesis of mixed ligand‐metal complexes of (2‐(2‐oxoacenaphthylen‐1 ylidene)hydrazinecarbothioamide) (L1) and carbamothioyl‐2‐chloronicotinohydrazonic acid (L2) and imidazole (im), triphenylphosphine (PPh3) and pyridine (py) ligands with Cu (II), Zn (II), Fe (II) and Co (II) salts.The chacterization was done through FT‐IR, NMR, UV‐visible, and elemental analysis. The X‐ray diffraction (XRD) patterns of [Cu(L1)(im)2(SO4)] demonstrated the crystalline morphology. In the FT‐IR spectra of the ligands, the characteristic frequencies corresponding to ν(C=N) (imine) and ν(C=S) (thiocarbonyl) were observed around 1650 and 1130 cm−1 respectively, which shifted upon complexation. In the 1H NMR spectra, the peak due to the NH proton was observed downfield, whereas that of ‐NH2 was observed comparatively upfield owing to its secondary amine nature. The molecular docking was performed against transforming growth beta (tgf‐β), protease of SARS‐CoV‐2 (Mpro) and aspartate kinase (Asp) kinase.The molecular simulation with the docked complex of [Zn(L2)(py)2(SO4)] and [Zn(L1)(PPh3)2(SO4)] with Asp kinase showed significant stability during the simulation time of 100 ns. The relative free energies of the simulated complexes were calculated with the molecular mechanics Poison‐Boltmann surface area (MM‐PBSA). The complexes were tested against ten bacterial strains and showed enhanced antibacterial activity than the ligands. [Cu(L1)(im)2(SO4)], [Zn(L1)(im)2(SO4)], [Fe(L1)(im)2(SO4)] and [Co(L1)(im)2(Cl2)] were found to be active against E.coli. [ABSTRACT FROM AUTHOR]

Copper(II) complexes with an α-diimine show a wide variety of biological activities, such as antibacterial, antifungal, antioxidant and anticancer. In this work, we synthesized and structurally characterized two novel Cu(II) complexes with methyl 3-formyl-4-hydroxybenzoate (HL) and α-diimines: 2,2′-bipyridine (bipy) and 1,10-phenanthroline (phen). Crystal structure analysis shows that the formulas of the compounds are [Cu(bipy)(L)(BF4)] (1) and [Cu(phen)(L)(H2O)](BF4)·H2O (2), with BF4− as a ligand in complex 1, which is rarely coordinated to metals. Both complexes have a square pyramidal geometry, while DFT calculations showed that the most stable structures of complexes 1 and 2 in a water/DMSO mixture are square-planar derivatives [Cu(bipy)(L)]+ and [Cu(phen)(L)]+. The antibacterial activity of compounds was evaluated in vitro on four Gram-negative and four Gram-positive bacterial strains. Complex 2 showed greater antibacterial activity towards all bacterial strains comparable to the control compound Amikacin. Complex 2 exerted a strong cytotoxic effect against the tested cancer cell lines (IC50 values ranging from 0.32 to 0.44 μM). Both complexes caused apoptotic cell death in HeLa cells and a noticeable in vitro antiangiogenic effect. In the concentration range of 5 to 100 μM, the complexes showed the absence of a genotoxic effect and displayed a protective effect against oxidative DNA damage induced by H2O2 in human peripheral blood cells. The interaction between the compounds and calf–thymus DNA was evaluated by diverse techniques suggesting a tight binding, which was also confirmed by molecular docking. In addition, it was found that the complexes bind tightly and reversibly to bovine and human serum albumin. [ABSTRACT FROM AUTHOR]

A series of transition metal complexes of Mn(II),Co(II), Ni(II), Cu(II), Zn(II) and VO(II) have been prepared by using the Schiff base ligand (L) derived from 4-aminoantipyrine and 5-chlorosalicylaldehyde. The structural properties of Schiff base ligand were characterized by mass, FT-IR, UV--Vis, ¹H-NMR spectroscopy, etc. Also, metal complexes were studied by P- -XRD, elemental analysis, thermogravimetric studies along with various biological activities. The micro analytical data revealed that, the metal complexes have 1:1 stoichiometry composition of M:L. Generally, it is observed that prepared metal complexes show better antifungal, antibacterial and anticancer activities than its Schiff base ligand. [ABSTRACT FROM AUTHOR]

The ligand, N′-(furan-2-ylmethylene)-2-hydroxybenzohydrazide (H2L), was synthesized characterized through various spectral studies which cleared out that the free ligand existed in keto form. The ligand upon reaction with Cu(II), Co(II), Ni(II) and Zn(II) acetates yielded complexes with stoichiometric ratio 1:2 (M:L) which has been validated through the elemental and mass spectral measurements. The IR and NMR spectral studies of the isolated complexes disclosed that the ligand chelated to metal ion in mononegative bidentate fashion via the azomethine nitrogen and deprotonated enolized carbonyl oxygen. Moreover, the DFT quantum chemical calculations designated that the ligand and Ni(II) complex exhibited the highest and lowest values of HOMO, LUMO energies and HOMO-LUMO energy gap, respectively. Furthermore, the in vitro cytotoxic activity towards HePG-2 and HCT-116 cell lines of the isolated compounds was investigated and the data cleared out that the ligand was more potent than the metal complexes. [ABSTRACT FROM AUTHOR]

An ionic liquid tagged schiff base, [1-{2-(2-hydroxybenzylideneamino)ethyl}-3-methylimidazolium]PF6 was synthesized from a functionalized ionic liquid (FIL) 2-aminoethyl-3-methylimidazolium hexafluorophosphate, [2-aemim]PF6 and salicylaldehyde without using any organic solvent. The Schiff base was used as a ligand to trap Mn(II), Co(II), Cu(II) ions from its corresponding metal acetates and to form the new transition metal complexes. The synthesized Mn(II), Co(II), Cu(II) complexes along with the Schiff base were characterized by ESI-MS, PXRD, UV-Visible, FT-IR, 1H NMR spectroscopic and analytical (elemental analysis and magnetic susceptibility measurements) methods. Based on these spectral analysis data tetra coordinated geometries were assigned for the newly synthesized metal(II) complexes. Antibacterial sensitivity of the Schiff base and the Mn(II), Co(II), Cu(II) complexes were evaluated against gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria to assess their minimum zone of inhibition. [ABSTRACT FROM AUTHOR]

Novel metal complexes of Au(III), Pd(II), Cu(II), Fe(II) and Mn(II) metals with unique asymmetrical bidentate Schiff base, obtained by condensation reaction between 1-Hydroxy-2-acetonaphthone and 4-Methoxyphenyl ethylamine, 2-(1-((4-methoxyphenethyl)imino)ethyl)naphthalen-1-ol (HL1). Synthesized Schiff base ligand and their metal complexes are well characterized by UV–Vis, FT-IR, NMR, LCMS, ESR, TGA–DSC, XRD and SC-XRD. Analytically proved the structure of metal complexes and ligand. Herein, our reports for the molar ratio of metal to ligand are1:2 in metal complexes with optimization. Interestingly, proved and analysed the interactions between the metal ions and ligand occurring deprotonated oxygen and Schiff base imine nitrogen using FT-IR, NMR, TGA–DSC and XRD. Also the geometries for the metal complexes such as square planar geometries for Au(III), Pd(II), Cu(II) complexes and octahedral geometries for Fe(II) and Mn(II) complexes. Synthesized metal complexes were examined for their in vitro anti-bacterial activity against the gram-negative bacteria E. coli, P. aeruginosa, and gram-positive S. aureus, B. subtilis, as well as their in vitro antifungal activity against the two fungus C. albicans, A. niger. According to the biological investigations, metal complexes are more effective against species of bacteria and fungi than non-complexed ligand. Interestingly, Pd(II) complexes have outstanding antioxidant activity, while Au(III) and Mn(II) complexes exhibit moderate to good antioxidant activity. [ABSTRACT FROM AUTHOR]

A novel series of metal complexes of Co(II), Ni(II), Cu(II), Zn(II) and Pd(II) with 4-((4-isopropoxybenzylidene)amino)-5-methyl-4H-1,2,4-triazole-3-thiol(IBMT) was synthesized and characterized by various physicochemical and spectroscopic techniques. The novel Schiff base (IBMT) was explored using IR, 1H, 13C-NMR and mass spectroscopy. The metal complexes were characterized via FT-IR, proton NMR, elemental analysis, ESR and electronic spectral studies. Magnetic moments and electrochemical behavior (Cyclic Voltammetry) of prepared complexes were also investigated. Thermogravimetric analysis revealed the number of coordinated water molecules and the thermal stability of metal complexes. In addition, various thermodynamic and kinetic parameters were determined using the thermal data. The fluorescence spectra of IBMT and all the coordinated complexes were also explored in different solvents of varying polarity. Based on the analytical and spectroscopic analysis, octahedral (Co, Ni, Zn) and square planner (Cu, Pd) environments were proposed and the novel complexes were formulated as [M(IBMT)(OAc)(H2O)n], M = Co, Ni, Cu, Zn, Pd and n = 1, 3 for 1:1 (M:IBMT) and [M(IBMT)2(H2O)n] n = 0, 2 for 1:2 (M:IBMT). Further, biological evaluation of Schiff base ligand and its complexes was also done against two gram-positive and two gram-negative bacterial strains and three fungal strains (C. Albicans, A. Niger and A. Clavatus). The newly synthesized complexes showed better or comparable antibacterial behavior (MIC = 50–250 μg/mL) than the standard drugs against E. Coli. The synthesized complexes, along with the ligand, were screened for in vitro antimalarial activity using chloroquine as a standard drug. [ABSTRACT FROM AUTHOR]

In this work, we presented a study of the structural formula for a new series of complexes with Ag(I), Cu(II), Zn(II), and Cd(II) derived from the guanine azo dye ligand 2-amino-8-((3-hydroxyphenyl)diazinyl)-1,7-dihydro-6H-purin-6-one (HAG), which is investigated using various physicochemical analyses, spectroscopic techniques (FT-IR, U.V-VIS, and 1H NMR), thermogravimetric analysis (TGA). In addition, elemental analyses, magnetic susceptibility, and molar conductance measurements were all stabilized. As well as the mole ratio, stability constant, and Gibbs free energy were studied for all complexes, where they showed high stability and spontaneous synthesis. The Cu(II) complex was suggested to have octahedral stereochemistry, while the Ag(I), Zn(II), and Cd(II) complexes were suggested to have tetrahedral stereochemistry. The ligand has been demonstrated to be a useful acid-base indicator, and it has been shown that the ligand (HAG) and its complexes exhibit high photostability and have various colors that can be used to dye wool materials. [ABSTRACT FROM AUTHOR]

In this work, combining acyclovir with ciprofloxacin (CCP), a new Schiff base and its metal complexes with iron (III), manganese (II), copper (II), zinc (II), and calcium (II) ions are synthesized and structurally characterized by XRD, SEM, 1H NMR, 13C NMR, FT-IR, and UV-Visible spectral techniques. Furthermore, molecular docking studies were carried out, and the complexes were tested to resolve any potential hangups in opposition to the Herpes virus and DFT calculation studies. In addition, the metal complexes and ligand were screened against antibacterial strains of one grampositive bacteria (Staphylococcus aureus) and three gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia), and it was established that these complexes demonstrate dissimilar bustles of inhibition on the enlargement of the bacteria. [ABSTRACT FROM AUTHOR]

The ligand N-{[(phenyl amino) thioxomethyl] hydrazino carbonyl methyl} trimethyl ammonium chloride (PTHAC) was prepared by the refluxing phenyl isothiocyanate and Girard-T (trimethyl ammonium-acethydrazide) in a molar ratio (1:1). The metal complexes derived from NiCl2.6H2O, CuCl2.2H2O and Co(CH3COO)2.6H2O were synthesized and purified. The PTHAC and its Cu(II), Co(II), and Ni(II) metal complexes(1–3) were characterized using a variety of various instrumental performances such as elemental analysis, magnetic moment, spectra (IR, UV–Vis, 1H NMR, mass) and thermal analysis (TGA and DTG).The results of element analysis, magnetic moment, spectra (IR, UV–Vis, 1H NMR, mass), and thermal (TGA and DTA) analyses provide the structures of the produced ligand and its (1–3) complexes. According to the spectroscopic results, PTHAC acts as an O, N and S tridentate donor, creating a mononuclear complex with copper(II), cobalt(II), and nickel(II) ions with an octahedral geometry. All of the atomic properties, including bond lengths, bond angles, HOMO, LUMO, dipole moments, and charges, have been determined. The cytotoxic activities of the PTHAC and the produced (1–3) complexes against breast carcinoma cells have been studied and correlated to the molecular modeling. When compared to the free ligand, CoII-L, and NiII-L, the CuII-L complex inhibits breast cancer cell growth more effectively. Furthermore, the PTHAC ligand was successfully applied for separation via flotation and spectrophotometric determination of Co(II) in several natural water, certified ore and pharmaceutical samples using oleic acid surfactant (HOL). At pH 6.5, PTHAC reacted with Co(II) to create a dark green (1:1) Co(II):PTHAC complex that was floated significantly using oleic acid (HOL) surfactant. The different experimental variable affecting the separation procedure e.g. pH, concentration of Co(II), HOL, PTHAC, temperature etc...., were investigated. Co(II) had a linear range of (0.1–7.0) mgL−1. In the aqueous and scum layers, the molar absorptivities for the coloured complex are 0.14 × 104 and 0.16 × 105Lmol−1 cm−1, respectively. The LOD was 0.04 mgL−1, which is related to Sandell sensitivity of 3.7 × 10−3 µg cm−2 with a preconcentration factor of 200 and a RSD, % (n = 5) less than 4.2%. In addition, the mechanisms involved in the process of coordination of PTHAC with Cu(II), Co(II) and Ni(II) and the mechanism involved in the process of flotation of the PTHAC-Co(II) complex using HOL surfactant were elucidated. [ABSTRACT FROM AUTHOR]

In this study, we report the cytotoxicity of a newly synthesized Schiff base HL ((E)-2-ethoxy-6((pyren-1-ylimino)methyl)phenol) and its derived metal complexes (Zn(II), Cu(II), Co(II), Cr(III), and Fe(III)) along with their structural characterizations by means of elemental analysis, magnetic moment, molar conductance, IR, UV-Vis, ESR, and mass spectrometry. The single X-ray diffraction of the HL shows that it exists in the phenol-imine form in its solid state. The NMR and IR data indicate that the bidentate binding of the Schiff base ligand with the metal center occurs during complexation through the azomethine nitrogen atom and the hydroxyl group oxygen atom of the 3-ethoxy salicylaldehyde. The electronic spectra and magnetic measurements indicate that the Co(II) complex has a tetrahedral geometry and that the Cr(III) and Fe(III) complexes have a distorted octahedral geometry. The ESR and electronic spectra suggest that the Cu(II) complex has a distorted tetrahedral geometry. The cytotoxic effects of the HL and all of the metal complexes were studied using human breast cancer (MCF-7) cells. The Cu(II) and Zn(II) complexes exhibited the highest activity against the tested cell line, with IC50 values of 5.66 and 12.74 μg/mL, respectively, and their activity was higher than that of the fluorouracil cancer drug against the MCF-7 cells (18.05 μg/mL). [ABSTRACT FROM AUTHOR]

Solid complexes (1–4) of Schiff base ((o‐tolylimino)methyl)phenol (HL) with manganese(II), cobalt(II), nickel(II), and copper(II) were synthesized in methanol under reflux. Schiff base (HL) was synthesized through condensation reaction of 2‐hydroxybenzaldehyde with o‐toluidine. Ligand (HL) and synthesized complexes (1–4) were characterized by using different spectroscopic techniques (UV–visible, FTIR, 1H NMR, mass spectrometry, powder X‐ray diffractometer [XRD]), magnetic measurements, and thermal gravimetric analysis. Spectroscopic analysis demonstrated that ligand being bidentate, in all the complexes, coordinates with metals through the N atom of azomethine group and O atom of the hydroxyl group. Molecular ion peaks (m/z) appear in the mass spectra of complexes confirm the proposed stoichiometry. TGA data of complexes 1 and 2 exhibited water molecules coordinated with the central metal ions (Mn2+ and Co2+). Magnetic Susceptibility analysis of metal complexes proposed octahedral geometry for Mn(II) and Co(II) complexes. Conductivity analysis was in good agreement with non‐electrolyte nature of metal complexes. Global reactivity data exhibited that metal(II) complexes are soft as compared to HL. Moreover, frontier molecular orbital (FMO) findings revealed that among the metal complexes, [Mn(L)2(H2O)2] 1 was having large energy gap showing greater stability and less reactivity, while [Ni(L)2] 3 was found most reactive among all of them. Values of chemical reactivity descriptors obtained denoted that synthesized metal complexes can be proved as efficient biological candidates owing to their reactivity patterns. In vitro antibacterial and antifungal activity of complexes and ligand were evaluated against different strains of bacteria (Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus,and Bacillus subtilis) and fungi (Candida albicans, Aspergillus niger, Trichoderma harzianum, and Aspergillus flavus) via disc diffusion method. The bacterial and fungal growth more efficiently inhibited by the use of metal complexes (1–4) than ((o‐tolylimino)methyl)phenol (HL). [ABSTRACT FROM AUTHOR]

Developing a new generation of anticancer metal-based drugs that can both kill tumor cells and inhibit cell migration is a promising strategy. Herein, we synthesized three Cu(II), Zn(II), and Mn(II) complexes derived from 5-chloro-2-N-(2-quinolylmethylene)aminophenol (C1–C3). Among these complexes, the Cu(II) complex (C1) showed significantly greater cytotoxicity toward lung cancer cell lines than cisplatin. C1 inhibited A549 cell metastasis and suppressed the growth of the A549 tumor in vivo. In addition, we confirmed the anticancer mechanism of C1 by triggering multiple mechanisms, including inducing mitochondrial apoptosis, acting on DNA, blocking cell cycle arrest, inducing cell senescence, and inducing DNA damage. [ABSTRACT FROM AUTHOR]

New series of Cu(II) and Mn(II) complexes with Schiff base ligands derived from 2-furylmethylketone (Met), 2-furaldehyde (Fur), and 2-hydroxyacetopheneone (Hyd) have been synthesized in situ on SBA-15-NH2, MCM-48-NH2, and MCM-41-NH2 functionalized supports. The hybrid materials were characterized by X-ray diffraction, nitrogen adsorption–desorption, SEM and TEM microscopy, TG analysis, and AAS, FTIR, EPR, and XPS spectroscopies. Catalytic performances were tested in oxidation with the hydrogen peroxide of cyclohexene and of different aromatic and aliphatic alcohols (benzyl alcohol, 2-methylpropan-1-ol, and 1-buten-3-ol). The catalytic activity was correlated with the type of mesoporous silica support, ligand, and metal–ligand interactions. The best catalytic activity of all tested hybrid materials was obtained in the oxidation of cyclohexene on SBA-15-NH2-MetMn as a heterogeneous catalyst. No leaching was evidenced for Cu and Mn complexes, and the Cu catalysts were more stable due to a more covalent interaction of the metallic ions with the immobilized ligands. [ABSTRACT FROM AUTHOR]

By reactions of di(4-halophenyl)maleindinitriles with magnesium and zinc(II) acetates in boiling ethylene glycol, Mg(II)-octa-(4-chlorophenyl)tetraazaporphyrin, Mg(II)-octa-(4-fluorophenyl)-tetraazaporphyrin, Zn(II)-octa-(4-chlorophenyl)tetraazaporphyrin, and Zn(II)-octa-(4-fluorophenyl)tetraazaporphyrins were synthesized. The cyclomerization of diphenylmaleinitrile with zinc acetate in ethylene glycol resulted in Zn(II)-Octaphenyltetraazaporphyrin. The corresponding Cu(II) and Mn(III)-octaphenyltetraazaporphyrins were synthesized in dimethylformamide using the metal exchange reaction of halogen-substituted magnesium complexes with copper(II) and manganese(II) chlorides. The obtained compounds were identified by electron absorption, IR, and 1H NMR spectroscopy, and mass spectrometry. The photochemical stability of the synthesized complexes was studied. [ABSTRACT FROM AUTHOR]

Bio-compatible water-soluble conjugates of Co(II), Cu(II) and Zn(II) (1–3), [Co(Boc- L -valine)2(imidazole)2], [Cu(Boc- L -valine)2(imidazole)2], and [Zn(Boc- L -valine)2(imidazole)2], were synthesized and comprehensively characterized by various spectroscopic techniques (UV–visible, FT-IR, ESI-MS, EPR, 1H NMR, 13C NMR) and single crystal X-ray diffraction which showed that the complexes 1–3 crystallized in an orthorhombic crystal system, in a slightly distorted octahedral geometry having the space group P21212. Density functional theory calculations were performed to correlate the energy of frontier molecular orbitals with the stability and reactivity of the complexes. In vitro DNA binding interaction studies of complexes were performed by employing various biophysical techniques and their corroborative results revealed (i) the electrostatic mode of binding in the groove region of DNA, (ii) pBR322 plasmid cleavage at a low concentration of 5–12.5 μM via an oxidative pathway in complexes 1 and 2 and the hydrolytic mechanism in the case of 3, (iii) changes in the 1H NMR chemical shift values of the NH2 group of GMP after interaction with complex 3, (iv) alteration in the EPR parameters of complex 2 after complexation with DNA, (v) SOD mimetic activity of complex 2 with the IC50 value of 2.08 μM and (vi) a good and selective cytotoxicity profile against chemo-resistant MCF-7 and MDA–MB–231 cancer cell lines by complex 1. Molecular docking studies complemented the spectroscopic results and confirmed the electrostatic interaction of complexes in the groove region of DNA. [ABSTRACT FROM AUTHOR]

Due to the obvious numerous economic and technical consequences of the corrosion process, its inhibition is one of the most critical aspects of current research. A corrosion inhibitor for the bis-thiophene Schiff base copper–metal complex Cu(II)@Thy-2 was investigated here, which was synthesized via a coordination reaction with a bis-thiophene Schiff base (Thy-2) as a ligand and copper chloride (CuCl2-2H2O) as a ligand metal salt. When the corrosion inhibitor concentration was increased to 100 ppm, the self-corrosion current density Icoor reached a minimum of 2.207 × 10−5 A/cm2, the charge transfer resistance reached a maximum of 932.5 Ω·cm2, and the corrosion inhibition efficiency reached a maximum of 95.2%, with the corrosion inhibition efficiency showing a trend of increasing first and then decreasing with concentration increase. After adding Cu(II)@Thy-2 corrosion inhibitor, a uniformly distributed dense corrosion inhibitor adsorption film formed on the surface of the Q235 metal substrate, significantly improving the corrosion profile compared to both before and after the addition of the corrosion inhibitor. Before and after the addition of corrosion inhibitor, the metal surface's contact angle CA increased from 54.54° to 68.37°, showing that the adsorbed corrosion inhibitor film decreased the metal surface's hydrophilicity and increased its hydrophobicity. [ABSTRACT FROM AUTHOR]

The combining of two ligands, barbituric acid (HL1) and thiobarbituric acid (HL2), to produce novel metal complexes with different metal chlorides (Cd(II), Co(II), Cu(II), and Fe(III) chlorides) in a ratio of 1:1:1 was studied. Furthermore, the obtained mixed complexes were confirmed through different analyses, such as elemental analysis and spectral analysis investigations. Moreover, TGA analysis was utilized to study the thermal stability, whereas all kinetic parameters were derived using the Coats–Redfern approach. Additionally, the crystallinity of these metals was analyzed through an XRD pattern with different potentials. The investigated complexes demonstrated excellent antimicrobial and antitumor activity against the A549 and Caco2 cell lines, with Co(II) and Cu(II) complexes demonstrating superior activity over other complexes, as confirmed by docking analysis with various proteins such as PDBID:3t88, PDBID:2wje, PDBID:4ynt, PDBID:1tgh, PDBID:2ito, and PDBID:1nun. In addition, the optimization of ligands and complexes on a DFT/B3LYP/LANL2DZ basis is used to assess their stability and determine physical descriptors, frontier molecular orbitals (FMOs), electrostatic potentials (ESPs), and molecular electostatic potentials (MEPs). Furthermore, the electrochemical characterization and electrocatalytic properties of metal complexes have been evaluated by using cyclic voltammetry and electrochemical impedance spectroscopy electrochemical analyses. [ABSTRACT FROM AUTHOR]

Schiff base ligands are chemical compounds having diverse biological activities like industrial, agriculture and pharmaceutical. The current work discusses the evaluation of the biological properties of different synthesized mononuclear Fe(II), Co(II), Ni(II) and Cu(II) complexes. The complexes were synthesized using a condensation reaction which demonstrated the appearance of White, Cream, Black and Green. Biological activities for synthesized metal complexes were assessed against S. aureus, B. cereus, E. coli and P. aeruginosa and by comparing the zones of inhibition it can be depicted that metal complexes are fairly more effective inhibitors of gram-positive bacteria. Furthermore the antioxidant potential of these complexes was also evaluated and it concluded that copper complexes showed promising antioxidant activity which is higher in association with Ni(II), Fe(II), and Co(II). Hence, these metal complexes were biologically active and further studies are required. [ABSTRACT FROM AUTHOR]

Three new mixed Ni(II), Co(II) and Cu(II) complexes have been created using 2-((2-mercaptophenylimino)methyl)-4- methoxyphenol and 1,10-phenanthroline. FT-IR, Elemental analysis, magnetic susceptibility, UV-Vis and molar conductivity technique have all been used to explore the structural characterisation of these compounds. Magnetic susceptibility readings for the L-Cu, L-Ni, and L-Co complexes were 1.97 BM, 2.92 BM, and 2.84 BM, respectively. The L-Co complex is thought to be antiferromagnetic. The structures of the mixed ligand metal complexes are thought to be octahedral geometry. There are no conductivity properties in the complexes; however, they exhibit molar conductivities that range from 2.46 to 9.04 μS/cm. [ABSTRACT FROM AUTHOR]

Cu(II), Ni(II), Zn(II), Co(II), Fe(II), Mn(II) carboxylates containing a pharmacophoric glycoluril fragment were obtained for the first time. The proposed structure of the complexes was established using elemental analysis, spectral methods, and magnetochemistry. Structure of one of the copper(II) complexes was proved by X-ray diffraction analysis. Antibacterial and fungicidal activity of all the compounds was studied. It was shown that the starting acids are inactive, while some complexes exhibit antibacterial activity. [ABSTRACT FROM AUTHOR]

In the current study, uni‐metallic Cu2+, Ni2+, Mn2+, Co2+, and Zn2+ complexes of ONN‐tridentate dihydrazone‐oxime incorporating indolin‐2‐one moiety (HL,1) were synthesized and structurally characterized employing elemental, spectral, thermo‐gravimetric, magnetic, and molar conductivity measurements, to investigate the structure and composition of these new uni‐metallic complexes. According to the results of several analyses, the dihydrazone‐oxime behaved as a mono‐negative or neutral tridentate ONN chelator bound the metal cations in molar ratio (1M:1L) through the isatinic carbonylic oxygen, azomethine nitrogen, and nitrogen atom of deprotonated/protonated oximatic moiety forming uni‐metallic complexes with formulae [M(L)XYZ(H2O)].nH2O (where M = Cu2+ (2–4), Ni2+, Mn2+, Co2+, or Zn2+, X = Cl, CH3COO, or NO3, Y = H2O or 0, Z = H2O or 0, n = 2, 0) and [Cu (HL)(SO4)(H2O)]. The Cu2+ complexes were found to have a tetragonally distorted octahedral or square pyramidal geometry, whereas those of Mn2+, and Ni2+, exhibited a tetrahedral geometry but Co2+ complex demonstrated a distorted octahedral geometry. Based on DFT‐B3LYP technique and 6‐311G++(d,p) basis set, The DFT data confirmed the structural investigation of dihydrazone‐oxime and its complexes, revealing that the complexes reactivity is more than un‐complexed dihydrazone‐oxime. Moreover, quantum chemical parameters of dihydrazone‐oxime and its uni‐metallic complexes like the energies of both lowest unoccupied molecular orbital (ELUMO) and highest occupied molecular orbital (EHOMO), separation energy (ΔE = ELUMO − EHOMO), chemical potential, absolute electronegativity, absolute hardness, and absolute softness were obtained. According to the thermogravimetric analysis, the complexes breakdown in two to four disintegrating phases in range of temperature 25°C to 575°C leaving the oxide of metal or metal oxide contaminated with carbon. In vitro microbicide effect of the un‐complexed dihydrazone‐oxime and its uni‐metallic complexes toward various bacterial and fungal strains was tested by agar‐well diffusion method. It is demonstrated that the complexes are more effective than free dihydrazone‐oxime. The antitumor activity has been also analyzed against three cell lines including prostate adenocarcinoma (PC‐3), ovarian adenocarcinoma (SKOV3), and cervical cancer (HeLa) cell lines. Studies showed that all complexes have greater inhibition activity against the above three cell lines than the free dihydrazone oxime and the most effective compound was the Zn2+ complex (9) with IC50, 27.42, 35.16, and 46.77 μg/ml, respectively. [ABSTRACT FROM AUTHOR]

As previously reported, we have synthesized an azo azomethine ligand 4-((E)-(2,5 dichloro phenyl) diazenyl)−2-((E)-((4-hydroxyphenyl) imine) methyl) phenol (L). The synthesized ligand has been used to prepare copper(II), nickel(II), and cobalt(II) metal complexes and characterized using various analysis techniques. To identify complexes, methods, such as elemental analyses, electrical conductivity, IR spectroscopy, mass spectrometry, magnetic moment, vibrating sample magnetometry (VSM), 1HNMR, UV–Vis, and thermal analysis were utilized, and a mononuclear structure was proposed for all compounds and all the complexes are non-electrolytes in nature. The chelation of the ligands to the metal ions occurs through phenolic oxygen and nitrogen atoms of the azomethine group of the ligands. According to various analytical and spectral data, a square planar structure is proposed for copper and nickel metal complexes and a quadrilateral structure is proposed for cobalt complexes. The antibacterial properties of ligands and complexes of copper(II), nickel(II), and cobalt(II) were investigated in vitro on standard bacteria as well as on bacteria isolated from clinical specimens (urine). The results revealed that the ligand and its metal complexes had a very high antibacterial activity against Staphylococcus aureus, but were ineffective against other studied bacteria. The synergistic effect of the compounds with the three antibiotics (vancomycin (V), methicillin (M), and trimethoprim (T)) was also investigated, along with the cytotoxicity of its ligand and copper complex in HFF cell line. At a concentration of 3.90 μl of these compounds, cell viability was significant. The structure of ligand and complexes was optimized by DFT calculations. Computational methods were performed for deeper understanding of the interaction between ligands and metal by EDA calculations. This result confirmed that the bonding between ligands to metal was mainly covalent. The complexes investigated are reported for the first time. The search for new antimicrobial agents against Staphylococcus aureus is an urgent medical need. Therefore, sensitive and selective diagnosis of this pathogenic bacterium is of great importance, which has been obtained in this study. The compounds synthesized from among the nine gram-negative and gram-positive bacteria are only sensitive to Staphylococcus aureus bacteria. [ABSTRACT FROM AUTHOR]

Three Schiff base ligands [H2L1–H2L3] containing nitrogen/oxygen donor atoms and their Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized by stirring metal acetates with Schiff base ligands obtained from condensation reaction of 2-amino-6-chloro-4-nitrophenol with 5-chloro salicylaldehyde/3,5-dibromo salicylaldehyde/3-methoxy-5–nitro salicylaldehyde. The structural traits of the synthesized compounds were done by using elemental analysis, spectroscopic techniques (UV–Vis, 1H and 13C NMR, FT-IR), mass spectrometry and some physical studies (XRD, TGA). According to spectral data, ligands behave as a tridentate (ONO) and formed complexes with octahedral geometry. The thermogravimetric analysis revealed that metal complexes decay in multi-steps leaving metal oxide as an end product. Powder XRD study suggested crystalline nature of the compounds. The energy gap (HOMO–LUMO) and molecular electrostatic potential calculation were computed by using DFT/B3LYP/6-31G** basis set. Derived ligands and complexes were explored for in vitro antimicrobial potential toward two gram-positive bacteria, two gram-negative bacteria, i.e., S. aureus, B. subtilis, P. aeruginosa, E. coli, and two fungal strains, i.e., A. niger, C. albicans, through serial dilution method taking ciprofloxacin and fluconazole as standard. The investigated results showed that complexes are more potent than free Schiff base ligands. The Cu(L2)(H2O)3 (0.0115 μmol/mL) and Zn(L2)(H2O)3 (0.0115 μmol/mL) complexes were found to be more active among all the investigated compounds. Additionally, molecular docking studies were also performed for some compounds in the active site of DNA Gyrase enzyme (PDB code: 1AJ6), suggesting good hydrophobic interactions of compounds with the enzyme. [ABSTRACT FROM AUTHOR]

Template condensation between pentane-1,5-dial and triethylenetetramine in the presence of divalent metal salts in methanolic solution resulted in mononuclear 15-membered tetraazamacrocyclic Schiff base metal complexes, [M(C11H22N4)X2], where M = Co(II), Ni(II) and Cu(II), X = Cl− and C11H22N4 is the tetradentate macrocyclic ligand. The bonding and overall geometry of the complexes are inferred through elemental analysis, FT-IR, UV–vis, 1H/13C NMR, ESI-mass, molar conductance, magnetic susceptibility and TG measurements. On the basis of the absorption bands in UV–vis spectra and magnetic moment analyses, a six-coordinate octahedral geometry is proposed for all the metal complexes. The formulation of the metal chelates is compatible with the thermal decomposition profiles. Photocatalytic efficiency of the macrocyclic Ni(II) complex was studied using solar water-splitting. The in vitro antimicrobial activity of metal complexes has been tested against certain bacterial and fungal species. The scavenging ability of DPPH free radicals was used to test the antioxidant activity of the complexes. In addition, MTT assay was used to assess the cytotoxicity of Cu(II) chloro complex against L929 mouse fibroblast cell lines. [ABSTRACT FROM AUTHOR]

A new Schiff base, (N,N\‐phenylene‐(bis‐1‐ethyl‐6‐fluoro‐7‐(piperazine‐1‐yl)‐quinolone‐3‐carboxylic acid) and (Nor‐o‐phdn.2H2O), and its derived complexes with nickel (II), cobalt (II), copper (II), iron (III), yttrium (III), lanthanum (III), zirconium (IV) and uranium (VI) were synthesised and distinguished by different tools such as elemental analyses, magnetic properties, molar conductivity, spectroscopic methods (UV‐Vis., IR and 1H‐NMR), mass spectrometry and thermogravimetric analysis. Depending on the spectroscopic data, Schiff base Nor‐o‐phdn.2H2O is coordinated to metal centres as a potentially tetradentate ligand via N2O2 atoms. UV‐Vis. and magnetic data suggest an octahedral‐geometry for all mentioned complexes. Thermogravimetric analysis indicated the existence of water molecules inside and outside complex sphere. The thermodynamics‐related parameters were analysed through using Horowitz–Metzger and Coats–Redfern formula. Schiff base as well as its metal‐derived complexes were assessed for their antibacterial, antifungal and antiviral bioactivities. As anticipated, Schiff base and its metal complexes showed high antibacterial profile against Escherichia coli and Salmonellatyphi. In case of Staphylococcus aureus and Bacillus cereus, it was observed that metal‐derived complexes exhibited more bactericidal features than the uncomplexed ligands. However, there are no antifungal bioactivities detected. Regarding the antiviral bioactivity, we determined in an innovative manner the effectiveness of Schiff base and metal‐derived complexes on the replication of human cytomegalovirus (huCMV‐DNA). In this regard, we utilised a humanised mouse model (huNOG‐EXL) that was implanted with human immune system cells and was subsequently infected with huCMV. The infected mice divided into drug‐treated mice and the drug‐untreated vehicle control. After postinfection and during the course of treatment, Fe (III) and Zr (IV) complexes were impactful in obstructing huCMV replication by 10‐15 fold when compared with the vehicle control, concomitantly with inducing the immune recognition of T‐cytotoxic CD8+ cells towards the huCMV. The complexes are believed to be the best nominees for further research and development as huCMV inhibitors. [ABSTRACT FROM AUTHOR]

Schiff base ligand [3-(2-hydroxyphenylimino)-1,3-dihydroindol-2-one] was synthesized by the condensation reaction of isatin with 2-aminophenol. The Schiff base and its metal complexes with Co(II), Ni(II), and Cu(II) and ions were permeated by 1H NMR, IR, elemental analysis, ESI-MS spectroscopy, electronic spectroscopy, and some physicochemical measurements. The Schiff base behaved as a tridentate ligand in all metal complexes and was linked by azomethine nitrogen (=C=N). Supported by analytical data the metal-ligand stoichiometry in the formation of complexes was found as 1 : 2 molecular ratio. Based on analytical data allied with spectroscopic studies spilled that the Cu(II) complex preferred tetrahedral geometry, while Ni(II) and Co(II) complexes offered square planar and octahedral geometry, respectively. The complexes were undergone thermal analysis (TGA and DTG); complexes were found thermally stable up to 200°C. All the stable assembled compounds were assessed for antibacterial competency. The ligand and the complexes were played mild to sturdy antibacterial activity against numerous pathogenic bacterial species, although growth inhibitory activities of complexes were enhanced comparatively than their respective ligands. Additionally, molecular docking analysis and quantum computational calculations based on the density functional theory (DFT) approach were used to study the molecular characteristics of the novel complexes and provide in-depth insights into their involvement in their ability to restrict bacterial growth. [ABSTRACT FROM AUTHOR]

An ultrasound-assisted synthesis has been used for the preparation of novel benzothiazole Schiff bases (1-3) as ligands for Zn(II) and Cu(II) metal complexes. In this class of Schiff base ligands, the isolated complexes 1a and 2a appear to be the only ones that have structures which include both the Schiff base ligand and the hydrolysis product 2-aminobenzothiazole in the same complex molecule. The aldehydes formed by Schiff base hydrolysis formed a rare example of a trans-isomer in pentacoordinated 2,4-disubstituted benzaldehyde complexes. [ABSTRACT FROM AUTHOR]

• Synthesis of some new mixed ligand metal complexes. • Characterization of FEB, para and their metal complexes with different techniques. • Optimized geometries for the new complexes were done using DFT. • Evaluation of antibacterial, antioxidant and molecular docking activities for mixed ligand metal complexes was done. The synthesized mixed ligand metal complexes were achieved by a combination of febuxostat (2-(3-cyano-4-isobutyloxyphenyl)-4-methyl-5-thiazolecarboxylic acid) (FEB) and paracetamol (4‑hydroxy acetanilide) (Para) together with crucial biologically relevant elements. These elements, including Co(II), Cu(II), Zr(IV), and Ni(II) chlorides, play important roles in various biological systems and mechanisms, such as antioxidant, antimicrobial systems, and contribute to diverse functions and structures. To identify chemical formulae and structures of synthesized complexes, physical-analytical, spectroscopic (XRD, FT-IR, ESR, 13C NMR, 1H NMR, and UV-visible), mass spectrometry (MS), TG-DTG studies were used and supported by computational approaches. FT-IR and 1H NMR data revealed that FEB chelated through sulfur of thiazole ring as a mono-negative bidentate type and deprotonated oxygen of carboxylate group, according to lack of characteristic band at 1677 cm−1 and signal at δ = 13.37 ppm (-OH COOH), whereas Para chelated through nitrogen and oxygen of amide group as a neutral bidentate ligand. Magnetic moment and electronic spectra data revealed that complexes have an octahedral structure. The optical band gap (E g) for our compounds was calculated and according to E g values, all complexes were semi-conductors and fell into the class of solar materials compared with FEB and Para. XRD pattern showed the monoclinic polycrystalline structure for all compounds except the Zr(IV) complex was amorphous. Kinetic parameters of the thermal decomposition stages were calculated. DFT was utilized to confirm bonding mode for FEB and Para with metal ions and according to calculations of energy band gap (ΔE) of complexes, Cu(II) complex with smaller ΔE is more reactive but, Zr(IV) complex with higher ΔE is less reactive than FEB and Para. The antibacterial activity of FEB, Para, and their complexes were tested against two G-ve and three G +ve bacteria. Co(II) complex displayed remarkable effectiveness and high significance against all strains of bacteria, compared with other compounds tested. All compounds demonstrated antioxidant effects, Cu(II) and Zr(IV) show greater antioxidants than parent ligands with IC 50 values 0.040 and 0.057 mg/mL. The binding pattern and active site of all compounds were put through molecular docking studies and compared with empirical biological data. The synthesized metal complexes from febuxostat (FEB) and paracetamol (Para) identified by spectroscopic techniques (FT-IR, ESR, XRD, 1H NMR and UV–visible), mass spectrometry (MS), TG-DTG. The antibacterial activities were examined. The compounds have been tested for antioxidant activity. We performed molecular docking studies for our compounds. [Display omitted] [ABSTRACT FROM AUTHOR]

The work reports the pharmacological applications of non-radioactive metal complexes with bis(thiosemicarbazones) and bis(hydrazone)-derived ligands. The antimicrobial, antiparasitic, and antineoplastic effects of these complexes, together with investigations into the interactions of some complexes with biological targets aiming at understanding their modes of action are described. The potential applications of copper(II) complexes with bis(thiosemicarbazones) for treating neurodegenerative diseases and studies on their mechanisms of action are also discussed. [Display omitted] The present work describes the multiple pharmacological applications of non-radioactive metal complexes with bis(thiosemicarbazones) and bis(hydrazone)-derived Schiff base ligands. The antimicrobial, antiparasitic, and antineoplastic effects of these complexes, together with investigations into the interactions of some complexes with biological targets aiming at understanding their modes of action are described. The potential applications of copper(II) complexes with bis(thiosemicarbazones) for treating neurodegenerative diseases and studies on their mechanisms of action are also discussed. [ABSTRACT FROM AUTHOR]

• The new homoleptic Cu(II), Ni(II), Co(II), and Fe(II) complexes of Schiff Base Ligand Based on Hydrazone were synthesized. • The photoluminescence properties were studied. • All compounds were investigated cytotoxic activity on HTB-54 and BEAS-2B lung. • cell lines. In the present work, N' -(2‑hydroxy-5-nitrobenzylidene)thiophene-2-carbohydrazide (L) and its Cu(II), Ni(II), Co(II), and Fe(II) complexes have been prepared. Their chemical structures were characterized by elemental analysis, molar conductivity, FT-IR, UV–Vis, TGA, LC-MS/MS, 1H and 13C NMR (for ligand). Also, the photoluminescence properties of the free ligand and its metal complexes were investigated in DMF solution. The ligand is emissive at 430–630 nm range and the emission band is almost turned off upon complexation with Cu(II) and Fe(II) ions. Emission spectra of the Ni(II) and Co(II) complexes showed a blue shift compared to the free ligand. Also, in vitro cytotoxic activities of both ligand and its metal complexes against HTB-54 and BEAS-2B cells have been investigated. The [Fe(L) 2 ]⋅2H 2 O complex (IC 50 35.59 μM) showed better cytotoxic activity than cisplatin against HTB-54 cells. Moreover, the ligand and its Fe(II) complex had slight cytotoxic activity against BEAS-2B cell line. [Display omitted] [ABSTRACT FROM AUTHOR]

New manganese (II) and copper (II) metal complexes bearing derived sulfa drug ligands were found to be efficient antimicrobial and antineoplastic agents. [Display omitted] The present work deals with the synthesis, characterization, and pharmaceutical potential evaluation of new biologically active Mn(II) and Cu(II) complexes with Schiff bases derived from sulfamethoxazole. The coordination mode of the complexes, geometry, and general formula were determined using elemental analysis, emission atomic spectroscopy, molar conductance, magnetic measurements, TGA, FTIR, electronic absorption spectroscopy, SEM-EDX, and EPR spectroscopy. The results indicate that the Schiff base act as bidentate ligands binding to the metal ions via the nitrogen atoms of the sulfonamide and oxazole groups which leads to a distorted octahedral geometry around the central metals. The in vitro antimicrobial properties of the Schiff base ligands and their respective Mn(II) and Cu(II) complexes were evaluated against Gram-negative and Gram-positive (Escherichia coli klebsiella pneumoniae , Staphylococcus aureus, and Bacillus subtilis)) bacteria, and two fungal strains (Candida albicans , Aspergillus niger). The results assert that the complexes display excellent antimicrobial properties with low MIC values. Additionally, DPPH-scavenging assay results suggest that the coordination compounds could act as efficient antioxidant species. The in vitro cytotoxicity assay conducted on chronic myelogenous leukaemia cell lines (K562) showed that the coordination compounds exhibit potent anticancer activities. Furthermore, the pharmaceutical properties, including pharmacokinetics and toxicity, were examined by ADMET simulations and molecular docking studies were employed to assess interactions between the complexes and drug targets. The in vitro experimental data and in silico computational analysis revealed that the ligands and their respective coordination compounds as noteworthy candidates for drug development. [ABSTRACT FROM AUTHOR]

A pair of structurally similar dicyanamide bridged copper(II) and zinc(II) complexes [CuL(dca)]n (1) and [ZnL(dca)] n (2), were prepared from the fluorine containing Schiff base 5-fluoro-2-(((2-hydroxyethyl)imino)methyl)phenol (HL). The compounds were characterized by physico-chemical methods. Structures of the complexes were confirmed by single crystal X-ray diffraction. The Cu atom in complex 1 is in square pyramidal coordination, whereas the Zn atom in complex 2 is in trigonal bipyramidal coordination. The copper complex has effective Jack bean urease inhibitory activity, with IC50 value of 0.14 ± 0.12 µmol L-1. [ABSTRACT FROM AUTHOR]

This study has been designed to evaluate some expected synthesized metal complexes with some amino acids as antitumor agent. The metal complexes that were synthesized in this study were Fe (II) with Arg, Zn (II) with Arg, Cu (II) with Arg, Cu (II) with Gly, Fe (II) with His and Zn (II) with His. All of these metal complexes were characterized by elemental analysis, IR spectroscopy, X-Ray diffraction pattern, Mass spectra, Atomic absorption and Scanning Electron Microscope (SEM). The cytotoxicity effect was examined by MTT assay against cancer cell line. The result show Zn (II) with Arg has the more potency against tumor cell line then Fe (II) with His and last was Cu (II) with Arg. Overall; these findings have proved that synthesized complexes could be potent anti- cancer cell line in vitro. [ABSTRACT FROM AUTHOR]

Three new ONNO-donor tetradentate unsymmetrical salen ligands were synthesized by using o -phenyl diamine with substituted salicylaldehydes followed by a two-step reaction methodology. These three ligands by reaction with Cu(OAc) 2.4H 2 O produced three new monomeric Cu(II) complexes, [ Cu II (L 1−3 ) ] (1 – 3). Elemental analysis, IR, UV–vis, NMR, and HR-ESI-MS techniques were used to analyze and characterize all the synthesized ligands and their corresponding metal complexes. Molecular structures of 1 – 3 were confirmed by the single-crystal-XRD analysis. Furthermore, the DNA binding ability of these complexes was checked through UV–vis, fluorescence spectroscopy, and also by circular dichroism studies. All the complexes were found to show an intercalation mode of binding with the K b value in the range of 104–105 M−1. Finally, 1 – 3 was tested against two malignant (HeLa and A549) and non-cancerous (NIH-3T3) cell lines to check their in vitro antiproliferative activities. Among all, 1 is the most cytotoxic of the series having IC 50 values of 5.7 ± 0.9 and 6.0 ± 0.3 μM against HeLa and A549 cell lines, respectively. This result is also consistent with the DNA binding order. Furthermore, the apoptotic mode of cell death of all the complexes was also evaluated by DAPI, AO/EB, and Annexin V-FITC/PI double staining assays. Some new monomeric, [ Cu II (L 1–3 ) ] complexes of unsymmetrical salen ligands are reported. Biological potential has been explored in terms of their DNA interaction, and cytotoxicity against HeLa and A549 cell lines. [Display omitted] • Synthesis of novel mono-nuclear Copper(II) complexes. • Unsymmetrical salen ligands. • Investigation of DNA interaction. • Cytotoxic potential. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis and characterization of copper, nickel and palladium complexes bound by bidentate ligands with tunable H-bond donors. • X-ray diffraction analysis of depicts intramolecular H-bonding interaction between the two ligand scaffolds. • Variations on the primary , secondaryand tertiary coordination sphere lead to changes in the geometry of the metal complexes. • Analysis of the complexes in the solid state reveals that the H-bonding interactions can be disrupted, changing the geometry of the complexes. • DFT calculations explain why Cu favors twisted geometries while Ni and Pd favor square-planar geometries. In this article, we describe the synthesis and characterization of a family of copper, nickel and palladium complexes bound by bidentate ligands derived from ortho -phenylenediamine that contain tunable H-bond donors. The crystal structures of the reduced dianionic metal complexes (formulated as [MII(L2-) 2 ]2-) depict intramolecular H-bonding interaction between the two ligand scaffolds. Variations on the primary (Cu, Ni, Pd), secondary (H-bonding donor) and tertiary coordination sphere (solvent of crystallization and countercation), led to the isolation of the metal complexes in square-planar (SP) and/or twisted pseudo-tetrahedral geometry (TW). A detailed structural analysis of the complexes in the solid state revealed that the intramolecular H-bonding interactions can be altered by disrupting the bonds between the countercation, solvent of crystallization and the ligand scaffold, which leads to changes in the geometry of the complexes (SP or TW). DFT calculations are in agreement with our experimental observations, in which the Cu complexes were found to favor twisted geometries while the Ni and Pd complexes favored square-planar geometries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of the new Schiff base ligand. • Synthesis of metal complexes using Schiff base. • Characterizing the Schiff base and its metal complexes. • Antimicrobial and docking studies of the Schiff base and its metal complexes. New Schiff base ligand (E)-2-(((7-chloro-2-hydroxyquinolin-3-yl) methylene) amino)-3-phenylpropanoic acid was synthesized using 2,7-dichloroquinoline-3-carboaldehyde and Phenylanine in ethanol. Using new ligand Copper, Zinc and Nickel complexes were also synthesized and characterized using FTIR, UV–Vis, 1H NMR, 13C NMR, TGA-DTA, and pXRD spectroscopic techniques. From its FTIR spectra, the synthesized Schiff base ligand was verified to be a tridentate ligand containing ONO active binding sites. To evaluate the Schiff base and its metal complexes' antibacterial properties, the disc diffusion method was employed. The antibacterial activity the ligand at a concentration of 100 µg/ml against B. cereus , S. aureus , E. coli , and S. typhi were found to be 10.00 ± 0.41, 6.05 ± 0.21, 8.00 ± 0.408, and 7.17 ± 0.236, respectively, whereas its antifungal activity against C. albinas was found to be 11.25 ± 0.204. Zinc complex showed antibacterial activities against B. cereus (9.33 ± 0.62), S. aureus (12.08 ± 0.42), E. coli (9.50 ± 0.40), S. typhi (6.75 ± 0.20), C. albinas (10.33 ± 0.24) at a concentration of 100 µg/ml whereas the nickel complex exhibited a bit lower activities against B. cereus (6.05 ± 0.22), S. aureus (6.58 ± 0.11), E. coli (6.08 ± 0.11), S. typhi (6.50 ± 0.22), C. albinas (7.50 ± 0.25) at a concentration of 100 µg/ml. On the other hand, the copper complex showed relatively highest antibacterial activity against B. cereus (18.67 ± 0.41), S. aureus (25.05 ± 0.41), E. coli (21.08 ± 0.31), S. typhi (22.05 ± 0.07), and the antifungal activity against C. albinas was 24.08 ± 0.43 than the other two complexes and the ligand. The overall results showed that the copper complex was found to have good antibacterial and antifungal activities. This is mostly caused by its small crystalline size (29.7 nm), which was inferred from the pXRD results. [ABSTRACT FROM AUTHOR]

Hydrogen bonds of glycine complexes were calculated using quantum chemistry calculations at M06L-GD3/def2-TZVPP level and by analyzing the crystal structures from the Cambridge Structural Database (CSD). One hydrogen bond where amino acid plays the role of the H-donor (NH/O), and two where it plays the role of the H-acceptor (O1/HO, O1 is a coordinated oxygen atom, and, O2/HO, O2 is a non-coordinated oxygen atom) were investigated. The calculations were done on octahedral nickel(II), square pyramidal copper(II), square planar copper(II), palladium(II), and platinum(II) glycine complexes with different charges adjusted using water(s) and/or chlorine ion(s) as the remaining ligands. For NH/O hydrogen bond, interaction energies of neutral complexes are the weakest, from −5.2 to −7.2 kcal/mol for neutral, stronger for singly positive, from −8.3 to −12.1 kcal/mol, and the strongest for doubly positive complex, −16.9 kcal/mol. For O1/HO and O2/HO interactions, neutral complexes have weaker interaction energies (from −2.2 to −5.1 kcal/mol for O1/HO, and from −3.7 to −5.0 kcal/mol for O2/HO), than for singly negative complexes (from −6.9 to −8.2 kcal/mol for O1/HO, and from −8.0 to −9.0 kcal/mol for O2/HO). Additionally to the complex charge, metal oxidation number, coordination number, and metal atomic number also influence the hydrogen bond strength, however, the influence is smaller. For NH/O interactions, neutral complexes have the weakest interaction energies, followed by singly positive, while doubly positive have the strongest. For O1/HO and O2/HO interactions, neutral complexes are again more weakly bound, while singly negative have stronger interactions. Complex geometry and metal oxidation number influence the interaction less significantly. [Display omitted] • Hydrogen bonds between free water and different metal-chelated amino acids were investigated. • Nickel(II), copper(II), palladium(II), and platinum(II) glycine complexes were calculated. • Octahedral, square pyramidal and square planar glycine complexes were calculated. • The crystal structures of cobalt and copper amino acids were analyzed. • Complex charge affects the interaction energy and geometry the most. [ABSTRACT FROM AUTHOR]

Metal (M): primary ligand (HL 1): co-ligand (HL 2) complexes; characterized by analytical and spectroscopic techniques. The results of the elemental analysis show the formation of [HL1:M:HL2] complexes. The ligands act as a mononegative bidentate chelating agent coordinating through C=O, NH 2 and two OH groups by replacement of a proton from the latter groups. The interface between HL 2, complexes and calf thymus DNA (CT-DNA) displays hypochromism behavior. Antimicrobial properties of ligands and the synthesized complexes were also screened versus G+ve bacteria (S. aureus and B. cereus), G-ve bacteria (K. pneumoniae , Pseudomonas sp. and E. coli , and fungi (F. oxysporum , A. niger , and C. albicans). The obtained results revealed the strong antimicrobial action of metal complexes with MIC, MBC and MFC values ranged from 5 to 45 µg/ml. HL 1 showed higher antimicrobial and antioxidant activities than HL 2 and major of the prepared metal complexes. All metal mixed ligand complexes inhibited the multidrug-resistant bacterium; Klebsiella pneumoniae compared to the standard antibiotic, penicillin G. Also, all metal mixed ligand complexes showed potent antifungal activities against both Aspergillus niger , and Candida albicans. [Display omitted] • Metal (M): primary ligand (HL 1): co-ligand (HL 2) complexes are prepared and characterized. • The molecular docking between the proteins receptors and the ligands and its mixed ligand metal complexes was studied. • Antimicrobial properties of ligands and its metal complexes are screened versus G+ve bacteria, G-ve bacteria and fungi. The results revealed the strong antimicrobial action of metal complexes with MIC, MBC and MFC values ranged from 5-45 μg/ml. • HL 1 ligand showed higher antimicrobial and antioxidant activities than HL 2 and major of the prepared metal complexes. The current work was designed to prepare novel 1:1:1 Metal (M): primary ligand (HL 1): co-ligand (HL 2) complexes; [Cu(L 1)(L 2)(OH 2) 2 ] (1) , [Co(L 1)(L 2)]H 2 O (2) , [Ni(L 1)(L 2)(OH 2) 2 ] 0·.75H 2 O (3) and [Mn(L 1)(L 2)(OH 2) 2 ] 4·.5H 2 O (4) and [UO 2 (L 1)(L 2)] (5) from ligands 7-Formyl-8-hydroxyquinoline (oxine) (HL 1), 2-aminophenol (HL 2) and characterized by analytical and spectroscopic techniques. FTIR, mass spectra, ESR techniques, elemental analysis, and thermal analysis were used to characterize the newly formed complexes. The results of the elemental analysis show the formation of [HL 1 :M:HL 2 ] complexes. The ligands act as a mononegative bidentate chelating agent coordinating through C = O, NH 2 and two OH groups by replacement of a proton from the latter groups. The molecular docking between the protein receptors and the ligand (HL 1), ligand (HL 2) and its mixed ligand metal complexes (1 – 5) was studied. The interface between HL 2, complexes and calf thymus DNA (CT-DNA) displays hypochromism behavior. The binding value constant (Kb) are calculated and found to be 5.29 × 103, 8.49 × 104, 2.45 × 105, 2.96 × 104 and 1.16 × 104, 3.08 × 104 M−1 for HL 2 and its mixed ligand metal complexes (1 – 5) , respectively. Antimicrobial properties of ligands and the synthesized complexes were also screened versus G + ve bacteria (S. aureus and B. cereus), G-ve bacteria (K. pneumoniae , Pseudomonas sp. and E. coli , and fungi (F. oxysporum , A. niger , and C. albicans). The obtained results revealed the strong antimicrobial action of metal complexes with MIC, MBC and MFC values ranging from 5 to 45 µg/ml. HL 1 showed higher antimicrobial and antioxidant activities than HL 2 and major of the prepared metal complexes. All metal mixed ligand complexes inhibited the multidrug-resistant bacterium; Klebsiella pneumoniae compared to the standard antibiotic, penicillin G. Also, all metal mixed ligand complexes showed potent antifungal activities against both Aspergillus niger and Candida albicans. [ABSTRACT FROM AUTHOR]

• Two ferrocenyl Schiff bases and their copper and nickel complexes. • All the compounds have been characterized. • Complexes have better biological activities as compared to Schiff bases. • Copper complexes of both Schiff bases have good anti-diabetic and antioxidant activities. • Both copper complexes showed inhibition against α-Amylase, urease and lipase. Two new Schiff base ligands were synthesized by the reaction of ferrocenyl aniline with aromatic aldehydes which were used for the formation of copper, nickel, and cobalt complexes. The synthesized compounds were characterized by elemental analysis, UV–Visible, FTIR, 1H, and 13CNMR Spectroscopy. The synthesized compounds were screened for various biological activities. The compounds showed moderate to significant activities. From the result, it was clear that metal complexes exhibited significantly better activities than their parent ligands. For anti-bacterial activities, the disk diffusion method was used. In all synthesized compounds, Nickel complexes showed higher results against S. setubal. In anti-fungal activities, Sb1Ni(II) and Sb2Cu(II) showed good results against M. species and F. solani respectively. Copper complexes of both Schiff bases showed good anti-diabetic and antioxidant activities. Copper Complex (Sb1, Sb2) exhibited considerable inhibition against α-Amylase (50.12 %, 33.20 %), Urease (49.12 %, 47.20 %), and Lipase (49.12 %, 42.20 %) as well as remarkable antioxidant activities (45.22 % and 52.12 %) in DPPH assay respectively. Synthesis, characterization and biological evaluation of ferrocene based schiff bases and their complexes [Display omitted]. [ABSTRACT FROM AUTHOR]

[Display omitted] • Schiff base ligand prepared by 3,5-dichloro salicylaldehyde and 2-amino phenol. • The ligand based metal complexes used to prepared nanoparticles. • The prepared metal complex has excellent antibacterial activity. Some new transition metal complexes of Cobalt (II), Nickel (II), Copper (II), and Zinc (II) with Schiff base ligand resulting from the condensation of 3,5-dichlorosalicylaldehyde and 2-aminophenol were synthesized in an ethanolic medium. Both ligand/complexes were characterized by some physicochemical techniques such as FTIR, UV, NMR, Mass, TGA, and SEM. The CHN elemental analysis data showed the formation of 1:1 [M:L] complexes. Magnetic susceptibility balance helps to find the magnetic values of the metal complexes. The various nanoparticles were prepared from metal complexes. The invitro antimicrobial activity was screened against the pathogens. [ABSTRACT FROM AUTHOR]

Copper(II) complexes are interesting for cancer treatment due to their unique properties, including their redox potential, possible coordination structures with different ligands, the most diverse geometries, and different biomolecule reactivity. The present work synthesized new copper(II) complexes with Schiff-base (imine) type ligands using natural aldehydes such as cinnamaldehyde, vanillin, or ethyl vanillin. The ligands were obtained through the reaction of these aldehydes with the amines 1,3-diaminopropane, 2,2-dimethyl-1,3-propanediamine, or 1,3-diamino-2-propanol and characterized by 1H and 13C NMR, FTIR and ESI-HRMS. The complexation reaction used copper(II) as perchlorate salt, obtaining six new copper(II) complexes. The complexes were characterized using FTIR, UV–vis, elemental analysis, ESI-HRMS, and EPR. In addition, the interaction with the copper(II) complexes and serum albumin was investigated by electronic absorption, showing complex incorporation in the albumin structure. The cytotoxicity of the complexes was evaluated using MTT assay in neuroblastoma cell lines SH-SY5Y, CHP 212, and glioblastoma LN-18, and presented EC 50 values between 90 and 300 μM. Based on our results, a square-planar copper(II) complex derived from Schiff-base cinnamaldehyde was found here to possess significant potential as an anti-cancer treatment. Further investigation is required to explore this compound's benefits in cancer co-treatment approaches fully. Brazilian natural products for synthesizing Schiff bases formed new active Copper(II) complexes in neuroblastoma and glioblastoma cells. [Display omitted] • Schiff-bases derived from Brazilian natural products were utilized in the formation of Copper(II) complexes. • The newly synthesized copper(II) complexes have been found to exhibit cytotoxicity. • It appears that the geometry of complexes is crucial to ensuring biological activity. • Serum albumin can transport the complexes. [ABSTRACT FROM AUTHOR]

Four S-containing azo-compounds based on 1-phenyl-3-methyl-4-azopyrazole-5-one and 10 novel metal complexes of Cu(II), Co(II), and Ni(II) were isolated and studied systematically by X-Ray and spectroscopic methods as well as in vitro and in silico modeling of toxicity and biological activity. [Display omitted] • Four new S-containing azo-compounds based on 1-phenyl-3-methyl-4-azopyrazole-5-one and 10 their metal complexes of Cu(II), Co(II), and Ni(II). • The types of coordination of organic species were determined by spectroscopic analysis together with X-Ray analysis of a model complex. • The toxicity of the compounds was determined based on the nature of the diazo-component. • The solubilities, models of physiological fluids and possess lipophilic properties were determined. Four S-containing azo-compounds based on 1-phenyl-3-methyl-4-azopyrazole-5-one and 10 novel metal complexes of Cu(II), Co(II), and Ni(II) were isolated and identified by X-ray single crystal analysis, FTIR, 1H NMR, and UV–Vis spectroscopy. The hydrazo-forms of the organic species in a solid state and solutions were proven. Studies of proteolytic equilibria, as well as complex formation in solutions, allowed the calculation of acidity and formation constants of the complexes in ethanol aqueous solutions. The types of coordination of organic species were determined by spectroscopic analysis together with X-ray analysis of a model complex. The sulfonamide group seems not to be involved in coordination. The toxicity of the compounds was determined based on the nature of the diazo-component and increased by replacing a benzene ring with a naphthol fragment. Computer screening revealed that the studied compounds exhibited the highest likelihood of enhancing HMGSC2 expression and displayed potential as antipyretics and anti-tuberculosis agents. Additionally, their solubilities in n-hexane, 1-octanol, and phosphate buffer at pH 7.4 were assessed. These solvents serve as models of physiological fluids and possess lipophilic properties that aid in membrane penetration. Subsequently, the thermodynamic constants were calculated. [ABSTRACT FROM AUTHOR]

• New nano Co(II), Ni(II), Cu(II), Zn(II), Fe(III) complexes, and oxovanadium(IV), dioxouranium(VI) complexes of a new carbohydrazone ligand have been synthesized and characterized. • The DNA cleavage study demonstrated the ability of investigated nano Cu(II) complex to degrade DNA. • The biological activity studies reveal the high efficiencies of the screened complexes as antibacterial and antitumor agents. • The docking findings showed strong interactions of both the ligand and its examined Cu(II) complex with DNA. • The electrical conductivity study confirmed that the ligand, and its investigated nano Cu(II) complexes had semiconducting properties. New carbohydrazone ligand DCCHP, were prepared by condensing 5,6-diphenyl-4-carbohydrazide-3(2H)-pyridazinone and 3-formyl chromone. Moreover, the new nano Co(II), Ni(II), Cu(II), Zn(II), Fe(III) complexes, and oxovanadium(IV), dioxouranium(VI) complexes of the ligand DCCHP, in addition of new mixed-ligand complexes using 8-HQ or 2,2′-bipy as an auxiliary ligand, were synthesized. The newly synthesized compounds have been characterized using a variety of analytical and spectroscopic techniques. The results showed that the ligand acted as tridentate towards the metal ions. The complexes exhibited octahedral geometries. According to TEM analysis, the particles of the investigated complexes were located at the nanoscale with spherical and stick shaped. The computational molecular properties revealed that the examined metal complexes may have higher chemical reactivity than the free ligand. The inhibitory activity of the investigated compounds with DNA molecules [of the dodecamer sequence (PDB ID: 1BNA)] were studies by molecular docking simulation. The docking findings showed strong interactions of both the ligand and its Cu(II) complex 7 with DNA. The results of antimicrobial activities showed enhancement in activity of the free ligand upon coordination with the metal ions. Moreover, the nano Cu(II) complex 9 and the nano Zn(II) complex 12 exhibited strong antitumor activities against Hepatocellular carcinoma cell line (HepG-2 cells) with IC 50 values smaller than the standard drug cis-platin and may be act as promising antitumor agents against HepG-2 cells. The DNA cleavage investigation demonstrated the capacity of the ligand and its nano Cu(II) complex 7 to destroy DNA. The electrical conductivity study in solid-state confirmed that the ligand and its Cu(II) complexes had semiconducting properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel mixed ligand metal complexes of Cd(II), Cu(II), Co(II), and Zn(II) are synthesized with the antimicrobial drug; moxifloxacin (primary ligand) and hydrazine (ancillary ligand). • The characterization was carried out by UV–Vis, Atomic absorption, FTIR, powder XRD, microscopic (SEM), elemental (CHN), and thermal (TGA) techniques. • The pharmacological activities include; cytotoxicity (by hemolytic activity) antimicrobial activity, and antidiabetic potential through α-amylase inhibition assay. • The molecular docking study for supporting complexes as potent α-amylase inhibitors. In the current study, four new mixed ligand metal complexes of Cd(II), Cu(II), Co(II), and Zn(II) with moxifloxacin (used as a primary ligand) and hydrazine (as an ancillary ligand) were synthesized. The newly prepared organometallic compounds were characterized by using conventional spectroscopic (UV–Vis, Atomic absorption, FTIR, and powder XRD), microscopic (SEM), elemental (CHN), and thermal (TGA) techniques. The synthesized chelates were evaluated for cytotoxicity (by hemolytic activity) and antimicrobial activity against different bacterial (S. aureus, B. subtilis, E. coli, and P. multocidia) and viral (A. flavus, A. niger, R. solani, and A. alternata) strains. The prepared metal complexes were also in vitro assayed for antidiabetic potential through α-amylase inhibition assay, and the results were further verified through molecular docking studies. This study demonstrates that half of the new metal complexes are good antibacterial agents, and complex 2 was significantly active against all four assayed bacterial strains. All the synthesized mixed ligand metal complexes proved to have significant fungicidal activity. Complex 3 has proved to be potentially active (24.3%) against Aspergillus flavus with a higher activity as compared to the reference standard, i.e., fluconazole (23.5%). The hemolytic values of 6.07%, 4.94%, and 12.05% for metal complexes 2, 3, and 4, respectively, were in acceptable range and comparable to moxifloxacin, while higher (19.05%) for complex 1. Present work reveals that all the bi-ligand complexes are significant antidiabetic agents, where complexes 3 and 4, with 62.45% and 54.25% α-amylase inhibition, have a similar effect as that of the standard drug, i.e., Acarbose having 64.12% α-amylase inhibition. The molecular docking studies correspondingly prove these two compounds as potent α-amylase inhibitors. [ABSTRACT FROM AUTHOR]

• 3-aminonaphthalen-2-ol and 2,3-dihydroxybenzaldaheyde Schiff base (ligand) was polymerized with ammonium persulfate (NH 4) 2 S 2 O 8 for the synthesis of the poly-ligand (PL). • Metal poly-ligand complexes [M(PL) 2 ] were synthesized from interaction with various metal species such as Zn2+, Hg2+, Ni2+, Pb2+and Cu2+. • The structural analyses of the obtained PL and its metal complexes were performed with method and techniques such as 1HNMR , UV–Vis, FT-IR, TGA and SEM. • DNA binding, DNA cleavage, antioxidant and antibacterial activities of all compounds synthesized were investigated. New members are joining to the Schiff bases family every day. In our study, firstly a new Schiff base was abbreviated as ligand (L) that was synthesized via condensation reaction between 3-aminonaphtalen-2-ol and 2,3-dihydroxybenzaldaheyde. Then, poly-ligand (PL) was obtained in basic medium in the presence of ammonium persulfate (NH 4) 2 S 2 O 8 via poly-condensation reaction by using L. Metal complexes were synthesized from the interaction of PL with various metal species such as Zn2+, Hg2+, Ni2+, Pb2+and Cu2+. The structures of compounds were confirmed by FT-IR, UV–Vis, 1 HNMR and elemental analysis. Their SEM images were recorded at different sizes. Looking at the SEM images, it can be seen that the [Hg(PL) 2 ] metal complex is similar to the red blood cells. Thermal analyses of PL and its metal complexes [M(PL) 2 ] were performed. The biological properties such as DNA binding-cleavage, antioxidant and antibacterial activities of all synthesized compounds were investigated. According to the results, it was determined that such properties of its metal complexes were better than PL. For example, when the oxidative cleavage activity was examined, it was determined that [Cu(PL) 2 ] complex completely cleaved the DNA and also it denatured all DNA at higher concentrations (≥100 ppm). DNA binding for the poly-ligand and its metal complexes bounded to CT-DNA in electrostatic mode. The antioxidant activity results showed that [Hg(PL) 2 ] complex had a high inhibition value of 78.70±0.55% at 100 ppm. The [Hg(PL) 2 ] complex was much more effective against all bacterial strains. The antibacterial activity of [Cu(PL) 2 ] and [Zn(PL) 2 ] complexes showed the highest activity against B. subtilis strain at the concentration of 62.5 µg/mL. DNA binding was determined from the UV–Vis spectra of the interaction of the PL and its metal complexes with CT-DNA. According to these UV–Vis results, it can be said that the poly-ligand and its metal complexes bounds to CT-DNA in electrostatic mode. [Display omitted] [ABSTRACT FROM AUTHOR]