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Two novel complexes were synthesized by the reaction of benzothiazol‐pyrimidin‐2‐ylidene ligand (BTP) with Pd (II) and Fe (III) ions. A variety of various spectral and analytical methods (infrared, 1H/NMR, 13C/NMR, electronic spectra, CHN analyses, mass spectra, thermogravimetric analysis, and magnetic susceptibility) were used to characterize the investigated BTP ligand and its complexes. Correlation of experimental results with density functional theory calculation proves that the geometry of BTP‐Fe complex is octahedral, whereas BTP‐Pd complex is square planner. The catalytic effectiveness of BTP complexes were tested for three‐component condensation process under moderate and environmentally friendly reaction conditions. Moreover, the effects of different Lewis acid, basic, and ionic liquid catalysts, as well as solvent and catalyst dose on the catalytic reaction were investigated. Both catalysts demonstrated strong catalytic capability in the carefully regulated ideal reaction circumstances. Heterogeneous catalyst BTP‐Pd exhibited superior catalytic performance compared to homogeneous catalyst BTP‐Fe. All products were obtained in high TOF (turnover frequency) numbers in the presence of these catalysts, which indicate the high efficiency of these catalysts in the synthesis of dihydro‐7H‐5‐thia‐hexaaza‐s‐indacen‐6‐one derivatives. Moreover, the two catalysts' recycling and reusability in reactions were also investigated. Heterogeneous BTP‐Pd catalyst could be reused up to seven times with high efficiency, but the homogeneous catalyst (BTP‐Fe) could only be recycled up to four times. Furthermore, the mechanism of catalytic reaction was suggested and supported by DFT calculation. The simplicity, safety, stability, use of commercially available catalysts, quick reaction times, and excellent yields make it promising for future industrial use. [ABSTRACT FROM AUTHOR]

Ciprofloxacin (CIPH) was classified as one of the most effective quinolone antibiotics, which is commonly used to cure a wide range of infections resulting from Gram-negative and Gram-positive microorganisms. The complexes which formed due to the interaction of Ni(II), Zn(II), Cu(II), Gd(III) and Sm(III) with ciprofloxacin were characterized by CHN% analysis, conductivity, FTIR, electronic spectra, fluorescence measurements, and magnetic susceptibility, besides studying the complex–DNA interaction. Meanwhile, the molar conductance values (0.001 mol·L−1 in DMSO) revealed the electrolytic behavior of the complexes and could be designated with the A−B+ formula. In addition, the geometry of the compounds was confirmed from the electronic transitions as well as the μeff values as octahedral for all complexes. The postulated formula could be generally assigned as [M(CIP)a(CIPH)b(H2O)c](NO3)(H2O)n(C2H5OH)m. Moreover, the interaction between metal complexes and DNA revealed that the Cu complex had the highest binding constant. Nanotechnology was applied to synthesized compounds using silica nanoparticles (SiNPs), which were prepared using a sol–gel process. The silica nanoparticles were chemically functionalized for binding the ligand and its metal complexes; this enables the as-prepared compounds to enhance their features as a drug delivery platform. Meanwhile, the antimicrobial activity was tested for the free complexes and SiNPs composites. Collectively, Sm complex gave the largest zone of inhibition, while the Cu(II)–SiNPs composite showed the strongest potential to reduce the bacterial activity. Furthermore, the fluorescence data of CIPH, ligand–metal mixture and the effect of silica nanoparticles on them were studied. [ABSTRACT FROM AUTHOR]

In this article, we have reported the synthesis and structural characterization of complexes containing Co(III), Cu(II), Zn(II), and Hg(II) metal cations. The ligand potassium azepane-1-carbodithioate (acdt) behaves as a monodentate and bidentate and forms complexes with the metals mentioned above. We investigated the electronic and emission spectra of the ligand potassium azepane-1-carbodithioate (acdt) and its metal complexes [Co(acdt)3]·CHCl3 (1), [Cu(acdt)2] (2), [Zn2(μ2-acdt)2(acdt)2] (3), and [PhHg(acdt)] (4). A photoluminescence study was also carried out and the results revealed that all compounds are fluorescent. Furthermore, this synthesized ligand and its complexes are passed through to examine their cytotoxic activity against human breast cancer cell line MDA-MB-231 and results suggested that complex [Co(acdt)3]·CHCl3 has sufficiently better activity than others. Furthermore, we have explored the impact of the synthesized ligand and its transition metal complexes on glucose metabolism within the human breast cancer cell line MDA-MB-231. Inhibiting glucose uptake can induce starvation in cancer cells, potentially resulting in cell death due to energy deprivation. Our results indicate that the Co(III) complex-treated group exhibited a greater inhibition of glucose uptake compared to groups treated with ligands and other metal complexes such as Cu, Zn, and Hg. Furthermore, we also measured the extracellular NO level in the ligand and its metal complexes of Co(III), Cu(II), Zn(II), and Hg(II) treated MDA-MB-231 cells and results indicated that the free ligand and its metal complexes induced the production of nitric oxide in MDA-MB-231 cells. Among the four metal complexes, Co-complex 1 elevated the nitric oxide level in MDA-MB-231 cells to 75.91 μM. In contrast, the groups treated with the complexes of Cu(II) (2), Zn(III) (3), and Hg(II) (4) induced NO levels of 62.91, 49.24, and 33.10 μM, respectively. This suggests that complex 1 induces nitric oxide production and enhances oxidative stress in MDA-MB-231 cells more significantly compared to the groups treated with the free ligand as well as with metal complexes 2–4. Overall, the data strongly suggest that complex 1 exhibits significant anticancer activity against the human breast cancer cell line MDA-MB-231, making it a promising candidate for combating breast cancer progression. [ABSTRACT FROM AUTHOR]

The new Schiff base ligand was designed from a condensation reaction of isatin with 5‐amino‐2‐hydroxy benzoic acid. Then, the metal complexes were prepared. The structures of the prepared compounds were framed from thermogravimetric analyses (TG–DTG), mass spectrometry, elemental analyses, 1H‐NMR, IR, electronic spectra, UV–vis, and conductivity measurements. Surface and size morphology have been studied by X‐ray powder diffraction and scanning electron microscope (SEM) analysis. The IR spectra suggested that the ligand acted as bidentate coordinated with metal ions through deprotonated carboxylate oxygen atom and oxygen of phenolic group. With the exception of the complexes of Cr (III), Fe (III), and Cd (II), which were non‐electrolytes, the molar conductivities demonstrated the electrolytic behavior of all the rest complexes. The X‐ray diffraction (XRD) analysis patterns for the Schiff base complexes indicated their crystalline nature except the Co (II) complex which had amorphous structure. The ligand and its metal complexes were screened for their antimicrobial activities against two G‐positive, two G‐negative bacteria and against Aspergillus fumigatus and Candida albicans fungi. Additionally, the compounds were evaluated against the MFC‐7 breast cancer cell line for their anticancer activity. The outcomes demonstrated their strong antitumor activity. [Fe(HL)Cl2(H2O)2]0.5H2O complex has the lowest IC50 value = 9 μg mL−1. Molecular modeling studies for the ligand and its Co (II) and Fe (III) complexes were accomplished from density functional theory (DFT) analysis. From molecular docking study, the electrophilic moieties in both complexes displayed good binding interactions with the CDK6, aminoglycoside phosphotransferase, and CYP51 targeted proteins. [ABSTRACT FROM AUTHOR]

The current research focused on the Schiff base ligand (S,E)-2-((2-hydroxy-3-methoxybenzylidene) amino)-3-(1H-imidazol-4-yl)propanoic acid which synthesis by reacting L-histidine and 2-hydroxy-3-methoxy-benzaldehyde. Its complexes with Ce(III) and Fe(III) both in bulk and nano size were also synthesized. The ligand and its metal complexes were characterized by various physicochemical methods such as FT-IR, 1H NMR, 13C NMR, electronic spectra, XRD, TGA, and SEM. The synthesized ligand and its metal complexes were screened against different fungi. It was found from the results that the cerium nano complex shows a potent antifungal activity for indoor uses as wallpapers. [ABSTRACT FROM AUTHOR]

A new series of Co(II), Zn(II), Ru(III), and Ag(I) complexes with the ligand (Z)‐N′‐(1‐(thiophen‐2‐yl)ethylidene)‐2‐(p‐tolylamino)acetohydrazide (H2L) has been prepared. FT‐IR, 1H‐NMR, electronic spectra, powder X‐ray, and thermal behavior were applied to elucidate the structural composition of new compounds. The electronic spectra proved that the Co(II), Zn(II), and Ru(III) complexes possess tetrahedral geometry, except the Ag(I) complex is a binuclear complex. The mass spectrum of the Zn(II) and Ag(I) chelates and the molecular ion peak observed at m/z values equivalent to the calculated molecular weight confirmed the proposed structure. Also, the SEM scanning electron microscope technique explored the spherical shape of all chelates, and the nanoscale was confirmed through TEM; the transmission electron microscope tool that provided the 7.0 nm was achieved in the case of Zn(II) chelate. Geometry optimization for all synthesized compounds was estimated by density functional theory (DFT) method using the Gaussian09 program. Biological screening as an antimicrobial and antitumor was studied. The Ru(III) complex revealed the greatest antibacterial efficiency, followed by the Co(II) complex. Co(II) complex revealed a greater affinity against fungi such as Candida albicans and Aspergillus niger. All chelate‐induced antitumor effects against the MCF‐7 cell line, especially Ag(I) complex (IC50 = 62.36 μg/mL), exhibited the greatest efficiency. The activity sequence follows the order doxorubicin (standard drugs) > Ag(I) > Zn(II) > ligand < Ru(III) > Co(III) chelates. The molecular docking was performed and validated to support the biological results. [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]

A molecular rotor is created when a 2,1,3‐benzothiadiazole rotator is incorporated into a rigid arylene ethynylene framework supported by pyridine coordination to a metal (Ag+ or PdCl2) guest. Comparisons to a similarly sized naphthyl rotator via 1H NMR spectroscopy provide insights into the movement of these bicyclic rotators relative to the rigid stator framework. Chemical shift increases of 0.3 ppm, or more, upon metal complexation are consistent with through‐space interaction of the central arene with a bound PdCl2 guest. Further study via X‐ray crystallography illustrates that rotation of the 2,1,3‐benzothiadiazole unit in the solid state is likely hampered by relatively strong chalcogen bonding (N⋅⋅⋅S distance of 2.93 Å), forming 2S‐2N squares between benzothiadiazoles of neighboring complexes. Strong π–π interactions (3.29–3.36 Å) between neighboring complexes likewise restrict solid‐state rotation of the potential benzothiadiazole rotator. Modest changes to UV–vis spectra upon metal coordination suggest that electronic properties are mostly independent of stator configuration. [ABSTRACT FROM AUTHOR]

The use of microwave-assisted synthesis in the formation of coordination metal complexes has led to improved control of waste generation and reduced reaction times. In the present study, new Schiff base metal complexes of various metals, including ZrO (II), VO(II), Cr (III), Mn (II), Fe (II), Co (II), Ni (II), Cu (II), Zn (II), Cd (II), and Hg (II), were synthesized using microwave radiation. To characterize the synthesized metal complexes, several physical methods were used, including elemental analysis, FT-IR, molar conductance, electronic spectra, 1H-NMR, ESR, magnetic susceptibility, thermal, electrical conductivity, and XRD analysis. Elemental analysis revealed that the complexes were of the 1:1, 1:2, and 1:3 (M: L) types. The observed molar conductance values indicated that the complexes were non-electrolytes. The 1H-NMR spectral data suggested that the phenolic protons had been displaced during complexation. Thermo gravimetric analysis showed the presence of water molecules in the coordination metal complexes and confirmed the loss of water molecules in the first step, followed by the decomposition of the ligand in the subsequent step. The synthesized ligand and coordination metal complexes were also studied for their antibacterial and antifungal activity. They were tested against various bacteria and fungi, including Escherichia coli, Salmonella enteric, klebsiella pneumoniae, Staphylococcus aureus, Streptococcus agalactiae, Aspergillus niger, and Aspergillus flavus. The results indicated that some of the metal complexes showed significant antibacterial and antifungal activity. Overall, the use of microwave-assisted synthesis in the formation of coordination metal complexes has led to the synthesis of new metal complexes with potential antibacterial and antifungal activity. The various physical methods used for characterization have provided valuable insights into the properties and behaviour of these metal complexes. [ABSTRACT FROM AUTHOR]

Two tridentate-type Schiff-bases’ ligands: 2,6-bis[(salicylidene) hydrazinocarbonyl] pyridine (L) and 2,6-bis[(3-methoxysalicylidene) hydrazinocarbonyl] pyridine (L') are synthesized from the reaction of pyridine2,6-dicarbohydrazide with salicylaldehyde and 3-methoxy salicylaldehyde. The co-ordination behaviour of the (L) and (L') towards Cu(II) and Co(II) ions is investigated. The reaction of the Schiff-base ligands (L) and (L') with cobalt(II) and copper(II) ions in 1:3 molar ratio affords polynuclear metal complexes. The shifts of the some IR-bands’ spectra of synthesized complex in the selected vibrational bands in FT-IR indicate that Schiff bases behave as trilydentate ligands and co-ordinate to metal ions from phenolic oxygen atoms, amide and azomethine nitrogen atoms. The structure of the metal complexes exhibits octahedral arrangements. The antibacterial activity of the ligand (L) and its metal complexes against two bacterial species is studied. The Co(II) complex indicates a good inhibition activity. The structures of the ligands are elucidated by FT-IR, 1H-NMR, and UV–Vis electronic spectra. The characterization and structure elucidation of the complexes are achieved by FT-IR, UV–Vis electronic spectra. [ABSTRACT FROM AUTHOR]

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

This work underlines some important features for the research on metal complexes of Niclosamide as antioxidants and antimicrobial evaluation of some of these compounds as possible therapeutic agents. Niclosamide metal complexes show a significant leap in the study of antibiotic resistance bacteria including Methicillin Resistant S.aureus (MRSA). The synthesized metal complexes of niclosamide in our current innovation are highly effective at eliminating this destructive sort of bacteria. Niclosamide metal complexes were synthesized then characterized by elemental analysis, Infra‐Red, electronic spectra, magnetic susceptibility, Mass spectra and ESR spectra of Cu (II) complex to know their geometries and mode of bonding, with stoichiometry, 1 : 1 (M : L). All the Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ions complexes were proposed to be with distorted octahedral geometry. Powder X‐Ray Diffraction technique is being utilized to further investigation of synthesized Niclosamide metal complexes. Expo2014 software was also employed to solve the structure of these novel complexes which proven the distortion of crystal structure. The TGA and DTA curves were employed to derive the kinetic thermodynamic parameters. The thermal decomposition of the complexes ended with the formation of divalent metal oxide, MO or trivalent, M2O3 as a final product except in case of Hg complex. The results of the antimicrobial activity of tested new metal complexes compounds exhibited potent antibacterial and antifungal activities in comparison to the Niclosamide ligand as reference. Quantum chemical parameters were estimated and provided noticeable values which completely matched with antimicrobial results that [Mn(NIC)(Cl2)(H2O)2] ⋅ 0.4H2O has higher biological activity than ligand and other novel complexes. low concentration value of MIC results by 125 μg/ml for both niclosamide (NIC) complexes [Ni(NIC)(Cl2)(H2O)2] and [Cu(NIC)(Cl2)(H2O)2] ⋅ 2.5H2O with Methicillin Resistant S.aureus (MRSA) genus maybe a valuable data used to produce novel therapeutic agent. Depending on their structure and on the source of the oxidative stress, metal complexes of Niclosamide might act as antioxidants or pro‐oxidants. [ABSTRACT FROM AUTHOR]

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Synthesis of metal complexes has been made possible by the Schiff base ligand 2,2'-diphenylenebis(1,2-phenylenebis(azanylylidene))bis(methanylylidene))diphenyl. The ligand was synthesised by condensing 3-hydroxythiophene-2-carbaldehyde and benzene-1,2-diamine. UV-Visible, FT-IR, and certain physiochemical studies validated the structural and spectral features of the ligand and metals. For Schiff bases, it was found that the N and O atoms have been identified as ligand binding sites for metal ions. Evidence from molar conductance measurements suggests that the complexes are not electrolytic. TLC analysis was used to check the total responses. In addition to the tetrahedral geometry predicted by magnetic susceptibility data, electronic spectra for the [ZnC16H10O2N2S2], [SnC16H10O2N2S2], [VOC16H10O2N2S], [MgC16H10O2N2S] complexes indicated a square planar geometry, And their activity tested for using a disc diffusion technique. [ABSTRACT FROM AUTHOR]

Polydentate, unsymmetrical, and multi metal ion sensing Schiff bases comprised of ferrocenecarboxaldehyde attached azomethine group at one side and aromatic aldehyde linked imine on the other side have been synthesized. Cumulative addition of different metal salts solution to receptors solution, changes the electronic spectra contrarily and for the addition of Cu2+ ions, generation of MLCT charge transfer band responsible for the coordination of metal ion with a receptor is observed. Electrochemical data (Ep) arrived from the cyclic voltammograms suggest a quasi-reversible process. The modest concentration of metal ions required for effective sensing by the sensory material is calculated from the Ipa values observed for metal ion added and metal free sensor solutions. Inhibition zones noticed in in vitro analysis for two fungi, two gram positive and two gram negative bacterial stains interpret that the new compounds possess high antifungal activity. Binding energy calculation using molecular docking software also ascertains the antifungal bustle. [ABSTRACT FROM AUTHOR]

In this study, metal cefotaxime complexes of Ca(II), Cr(III), Cu(II), Zn(II), and Se(VI) were synthesized and characterized by elemental analysis, conductance measurements, IR, electronic spectra, magnetic measurements, 1HNMR, and XRD, as well as by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The lower values for molar conductance refer to the nonelectrolyte nature of the complexes. The FTIR and 1H-NMR spectra for the metal complexes of cefotaxime proved that the free cefotaxime antibiotic ligand acted as a monoanionic tridentate ligand through the oxygen atoms of lactam carbonyl, the carboxylate group, and the nitrogen atoms of the amino group. From the magnetic measurements and electronic spectral data, octahedral structures were proposed for the Cr(III) and Se(VI) complexes, while the Cu(II) complex had tetragonal geometry. This study aimed to investigate the effects of cefotaxime and cefotaxime metal complexes on oxidative stress using antioxidant assays including DPPH, ORAC, FARAB, and ABTS, a metal chelation assay, as well as the inhibition of the viability of cancer cells (HepG-2). Regarding the antibacterial activity, the cefotaxime metal complexes were highly effective against both Bacillus subtilis and Escherichia coli. In conclusion, the cefotaxime metal complexes exhibited highly antioxidant activities. The cefotaxime metal complexes with Zn and Se inhibited HepG-2 cellular viability. Thus, the cefotaxime metal complexes elicited promising results as potent antioxidant and anticancer agents against HepG-2, with potent antibacterial activities at a much lower concentration. [ABSTRACT FROM AUTHOR]

Isonicotinic acid N′-(10-oxo-10H-phenanthren-9-ylidene)hydrazide (HL) and its complexes ML2 and MHLCl2 [М = Cu(II), Ni(II), Co(II), Fe(II), and Zn(II)] were synthesized. The structure and properties of the obtained compounds were studied by 1H NMR, IR, and X-ray absorption spectroscopy. The hydrazide structure was determined by X-ray diffraction. Quantum-chemical calculations of its tautomeric forms and electronic absorption spectra were carried out. In ML2 chelate complexes, the ligand is coordinated to metal atoms in the enol form, whereas in MHLCl2 complexes it is coordinated in the keto form. [ABSTRACT FROM AUTHOR]

The metal (II) complexes of picolinic acid are prepared in non-aqueous medium and its complexes are characterized by spectral studies (Infra-red spectroscopy, UV-Visible spectroscopy, 1H-NMR spectroscopy and ESR spectroscopy), conductance, magnetic susceptibility and thermal analysis. On heating, the complexes decompose at temperature above 260oC. It revealed that all the complexes were stable. The FT-IR evidenced the C=O, C=complexes along with corresponding ligands. Thermogravimetric study showed that there is no water molecule in the complexes. The electrochemical behavior of all metal complexes was investigated. From the electronic spectra the geometries of cobalt, nickel and copper is found to be Octahedral, Octahedral, and Distorted octahedral respectively. The complexes of the ligand are evaluated for anti-microbial activity hostile to fungal and bacterial strains. The nickel (II) complex reveals excellent inhibition again the selected four bacterial strains compare with other complexes. [ABSTRACT FROM AUTHOR]

The metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) with glutamine were synthesized and characterized by elemental analyses, IR, electronic spectra, thermal analyses (TGA and DTA), nuclear magnetic resonance (1H and 13CNMR), electron spin resonance and effective magnetic moments. Four coordinated complexes were formed in case of Cu(II), Ni(II) and Zn(II) ions, while Co(II) formed six coordinated species. The as-prepared metal complexes were used as precursor of Co3O4, NiO, CuO and ZnO nanoparticles after calcination at 700 °C. The obtained nanoparticles were characterized by (X-ray powder diffractions) XRD and transmittance electron microscope (TEM). The average particle sizes as indicated from TEM images were found to be 64, 48, 55 and 64 nm for Co3O4, NiO, CuO and ZnO, respectively. Adsorption of methylene blue on the surface of Co3O4, NiO, CuO and ZnO nanoparticles was studied. They exhibited higher adsorption capacity than those prepared by co-precipitation method. NiO showed the highest removal capacity (95.6%) among the studied compounds. Langmuir adsorption isotherm and pseudo-second-order kinetic are the best models that fit the adsorption of methylene blue onto Co3O4, NiO, CuO and ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

Magnesium, copper, zinc, iron and selenium complexes of ceftriaxone were prepared in a 1:1 ligand to metal ratio to investigate the ligational character of the antibiotic ceftriaxone drug (CFX). The complexes were found to have coordinated and hydrated water molecules, except for the Se (IV) complex, which had only hydrated water molecules. The modes of chelation were explained depending on IR, 1HNMR and UV–Vis spectroscopies. The electronic absorption spectra and the magnetic moment values indicated that Mg (II), Cu (II), Zn (II), Fe (III) and Se (VI) complexes form a six-coordinate shape with a distorted octahedral geometry. Ceftriaxone has four donation sites through nitrogen from NH2 amino, oxygen from triazine, β-lactam carbonyl and carboxylate with the molecular formulas [Mg(CFX)(H2O)2]·4H2O, [Cu(CFX)(H2O)2]·3H2O, [Fe(CFX)(H2O)(Cl)]·5H2O, [Zn(CFX)(H2O)2]·6H2O and [Se(CFX)(Cl)2]·4H2O and acts as a tetradentate ligand towards the five metal ions. The morphological surface and particle size of ceftriaxone metal complexes were determined using SEM, TEM and X-ray diffraction. The thermal behaviors of the complexes were studied by the TGA(DTG) technique. This study investigated the effect of CFX and CFX metal complexes on oxidative stress and severe tissue injury in the hepatic tissues of male rats. Fifty-six male rats were tested: the first group received normal saline (1 mg/kg), the second group received CFX orally at a dose of 180 mg/kg, and the other treated groups received other CFX metal complexes at the same dose as the CFX-treated group. For antibacterial activity, CFX/Zn complex was highly effective against Streptococcus pneumoniae, while CFX/Se was highly effective against Staphylococcus aureus and Escherichia coli. In conclusion, successive exposure to CFX elevated hepatic reactive oxygen species (ROS) levels and lipid peroxidation final marker (MDA) and decreased antioxidant enzyme levels. CFX metal complex administration prevented liver injury, mainly suppressing excessive ROS generation and enhancing antioxidant defense enzymes and in male rats. [ABSTRACT FROM AUTHOR]

Schiff base ligand and its complexes were prepared and characterization using different mothed like electronic spectra (ultra-violate & Visible spectrum). FTIR magnetic moments measurements, bioactivity and molar conductivity measurements the geometry shape of the complexes is Tetrahedral geometry. The biological activity of prepared ligand and its complexes are study using Staphylococcus aureus, Escherichia coli and Candida albicans the result obtained complex were more active than ligand. [ABSTRACT FROM AUTHOR]

The synthesis of a new mixed Schiff-base and DTCs ligands and its metal complexes are reported. Schiff-base was prepared by reaction of ((E)-2-amino-6-(pyridin-2-yl diazenyl)phenol) with 4-(dimethylamino)benzaldehyde). The complexes were prepared by mixing the (2-(((E)-4-(dimethylamino)benzylidene)amino)-6-((E)-pyridin-2-yldiazenyl)phenol) ligand (HL) and (potassium diphenylcarbamodithioate) ligand (L) with the metal salts; Cobalt(II), Nickel(II), Zinc(II) and Cadmium(II) in a 1:1:1 mole ratio. Physico-chemical techniques were implemented, as required, to characterise the ligands and complexes. These include; elemental microanalysis, Fourier Transform Infrared Spectra, Electronic spectra and 1H-Nuclear magnetic resonance spectroscopy, chloride content, magnetic susceptibility and conductance. Thermal stability (TGA-DSC) of the ligand and selected complexes were also investigated. These analyses revealed the isolation of six and four coordinate structures in the solid and solution sate. The antimicrobial activity of the ligand and its complexes against bacterial strains species was examined. [ABSTRACT FROM AUTHOR]

A new bio-active Schiff base was synthesized from cinnamaldehyde and aniline and the Zn(II), Ni(II) metal complexes have been synthesized and structurally characterized by micro-analytical, magnetic property, conductivity, mass spectra, FT-IR, Electronic absorption spectra, ¹H-NMR, and 13C-NMR spectral studies. The Physico-chemical and spectral data show that the complexes have the composition of 1:1 type of metal with a ligand. Its electronic absorption spectra and magnetic study proposed the tetrahedral geometry for Zn(II) complex and octahedral geometry for Ni(II) complex. It was further supported by the mass and IR spectra; the biological activities of Schiff base and their metal complexes were carried out by the Agar disc diffusion method. The results confirmed that the metal complexes enhanced the bio-potential activities than the free Schiff base. [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 synthesis of the Schiff base ligand, (E)-4-methyl-N′-(2,4,5-trimethoxybenzylidene)benzohydrazide (HL), along with its Cu(II) and La(III) metal complexes (designated as M 1 L and M 2 L, respectively), was reported in the current study. The compounds were obtained through a reversible condensation reaction involving primary amine and carbonyl compounds. Characterization of the Schiff base ligand and its metal complexes was achieved through the use of various techniques, including powder X-ray diffraction, 1H NMR spectra, thermogravimetric analysis, elemental analysis, and FT-IR studies. Analysis of 1H NMR and FT-IR spectra reveals that the ligand demonstrates isobidentate behavior. The electronic spectra data indicates that the concentration of charge transfer transitions is most pronounced in the presence of the ligand, highlighting its significant role in facilitating charge transfer processes. The measurement of zones of inhibition (mm) against gram-positive and gram-negative bacteria, including Enterococcus faecalis , Escherichia coli , and Bacillus subtilis , was conducted at least three times under identical conditions for both the Schiff base ligand and its metal complexes. Molecular docking modeling was employed to determine the positioning of links, energy distribution, and molecular distances that contribute to the interactions among these complexes. The interactions observed indicate that the synthesized HL and its M 1 L and M 2 L complexes effectively engage with the protein receptor molecule, exerting a positive influence on the free binding energy. Based on interaction energy values, the M 1 L complex exhibits a notably more stable interaction and lower binding energy. According to interaction energy measurements, the M 1 L complex exhibited a significantly more stable connection and a lower binding energy. [Display omitted] In this current investigation, we have accomplished the synthesis of a Schiff base ligand termed (E)-4-methyl-N′-(2,4,5-trimethoxybenzylidene)benzohydrazide (HL) through a reversible condensation reaction, which engaged a carbonyl compound and a primary amine. This synthesized Schiff base ligand, HL, served as the foundation for the preparation of two metal complexes, namely, M 1 L (Cu complex) and M 2 L (La complex). To characterize these compounds, we employed various analytical techniques, including thermogravimetric studies, elemental analysis, powder X-ray diffraction, FT-IR spectroscopy and 1H NMR. The examination of powder X-ray diffraction data provided valuable insights into the crystalline structures of the Cu and La complexes. These shifts are indicative of structural changes in the complexes. Our electronic spectrum analysis revealed the pivotal involvement of the ligand in promoting charge transfer processes, substantiated by an increased concentration of charge transfer transitions observed when the ligand was present. Additionally, we evaluated the antibacterial efficacy of the Schiff base ligand HL and its metal complexes (Cu, La) against a spectrum of bacteria, encompassing both gram-positive (Bacillus subtilis, Enterococcus faecalis) and gram-negative (Escherichia coli) strains. In the current investigation, we utilized molecular docking techniques to explore the interactions between the synthesized HL and its M 1 L and M 2 L complexes with protein receptor molecules. These results highlighted the favorable binding energies and stable interactions of these compounds with the protein receptor, M 1 L displayed notably more stable interactions and lower binding energy compared to M 2 L. This suggests that M 1 L may have a stronger potential impact on the free binding energy and molecular interactions. [ABSTRACT FROM AUTHOR]

Ampicillin is a derived form of pencillin which is semi synthetic b-lactum antibiotic used to treat bladder infections, pneumonia, respiratory infection. Schiff's bases are the most widely studied chelating ligands in coordination chemistry. Recently metal complexes of Schiff bases particularly derived from carbonyl compounds base on hetero-cyclic rings have been the centre of attraction in many areas. Present paper brief the synthesis of AHMBL and its transition metal (II) complexes and also the coordination/characterization studies such as magnetic susceptibility, molar conductance, Electronic spectra, Thermal study, FT-IR, H-NMR, XRD and SEM. [ABSTRACT FROM AUTHOR]

The bimetallic complexes of 2,2′‐malonylbis(N‐phenylhydrazine‐1‐carbothioamide) have been prepared and characterized by elemental and spectral analyses. The free ligand exists in keto‐thione form, whereas in complexes it chelated to the metal ion in binegative tetradentate and neutral tetradentate manners. The electronic spectra and magnetic moment measurements showed that all the complexes have an octahedral geometry except the [Cu2(H2L)(OAc)2]EtOH complex which has square planar structure supported by the electron spin resonance (ESR) spectral data. In addition, thermal gravimetric analysis (TGA) carried out to clarify thermal stability of the ligand and its complexes. The optical band gap (Eg) was calculated using Tauc's equation and compared with their HOMO‐LUMO gap obtained from DFT quantum chemical calculations. Furthermore, the in vitro cytotoxic activity against Hela (Epitheliod Carcinoma) and WISH (Human amnion) cell lines of isolated compounds were examined. The data indicated that the ligand has very strong activity against Hela cell line and moderate activity against WISH cell line. Accordingly, the metal complexes showed more potent effect against Hela than WISH cell lines. [ABSTRACT FROM AUTHOR]

Mixed ligand Mn(II), Co(II), Ni(II), Cu (II), Zn(II), and Cd(II) complexes with (TMAP) Schiff base ligand and (8HQ) have been composition and analyzed. Diagnosis by, melting point, solubility, Electronic, mass and IRspectroscopic studies, conductivity elemental, thermoanalytical analysis displayed the forming of mononuclear complexes. Spectral studies results suggest an octahedral system or the metal (II) mixed complexes. The detainments of molar conductance of the mixed complexes in DMF coincide to electrolytic nature of the mixed complexes, consequently, these complexes could be subedited as [M(TMAP)(8Q)(H2O)]nX.yH2O (M=Co(II) and Cu(II) complexes(where n = 1, y = 0); [M(TMAP)(8Q)(H2O)]nX.yH2O (M = (where n = 1, y = 1 for Ni(II) complex and n = 1, y = 2 for Cd(II) complex) and [M(TMAP)(8Q)(H2O)]nX.yH2O (M = Mn(II) (n = y = 2) and Fe(III) (n = 3, y = 0)). On the principle of electronic spectra, magnetic moment studies, an octahedral structure has been designated for the metal complexes. Further parameters of the thermodynamic and kinetic for the various stages of decomposition were determined to utilize the Horowitz-Metzger and Coats-Redfern ways. Then, the ligand in rapprochement to metal complexes is tested for their anticancer and antimicrobial efficacy with breastic cancer cell line. The outcomes showed that the metal complexes are more active than the parent TMAP ligand but more active than (8HQ) free ligand. In these complexes, the metal ion chalets to the ligand through the azomethine linkage, (NH2) and imine(C=N) groups of trimethoprim drug. The outcomes of conductivity related that the complexes were all 1:1 electrolytes except Mn(II) and Zn(II) complexes are nonelectrolyte. The metal complexes were tested for their antimicrobial efficacies applying agar disc diffusion method and the outcomes related that they were active with bacteria pieces screened. [ABSTRACT FROM AUTHOR]

A series of C-centered heteroscorpionate-beared pyridinamine Mn (II), Ni(II), Cu(II) and Zn(II) complexes of the kind [M(L)2] have been prepared by utilizing the ligand (1,1-di(1H-imidazol-1-yl)-N-(pyridin-3-yl)methanimine. The parameters of geometric for the complexes were calculated utilizing studies of notional and UV-vis indicating octahedral geometry around metal(II) ion. Antioxidant the activity of nickel(II) and copper(II) complexes were evaluated against H2O2, ABTS, free radicals and DPPH. Antimicrobial efficacy of the metal(II) complexes were calculated versus two bacteria of (Staphylococcus aureus and Bacillus cereus) Gram(+ve) and two (Escherichia coli and Klebsiella pneumoniae) Gram(-ve), and two strains of fungal (Candida krusei, and Candida albicans). the interaction of complexes with (CDK2) has been studies of molecular docking. The cytotoxicity efficacy (in vitro) for complexes of Cu(II) and Ni(II) versus cell lines of (HeLa), (A549), and (MCF-7) cancer with MTT screening was used to investigate from cell line of (NHDF) that appears the good efficacy of Cu(II) complex. [ABSTRACT FROM AUTHOR]

New Schiff-base ligands bearing tetrazole moiety and their polymeric metal complexes with Co(II), Ni(II) and Cd(II) ions are reported. Ligands were prepared in a multiple-step reaction. The reaction of sodium 2,6- diformylphenolate and cyclohexane-1,3-dione with 5-amino-2-fluorobenzonitrile resulted in the isolation of two precursors sodium 2,6-bis((E)-(3-cyano-4-fluorophenylimino)methyl)-4-methylphenolate 1 and 5,5'- (1E,1'E)-cyclohexane-1,3-diylidenebis- (azan-1-yl-1-ylidene)bis(2-fluorobenzonitrile) 2, respectively. The reaction of precursors with azide gave the required ligands; sodium 2,6-bis((E)-(4-fluoro-3-(1H-tetrazol-5- yl)phenylimino)methyl)-4-methylphenolate (NaL) and (N, N'E, N, N'E)-N, N'-(cyclohexane-1,3-diylidene)bis(4- fluoro-3-(1H-tetrazol-5-yl)aniline) (L1). The reaction of these ligands with the appropriate metal ions gave polymeric metal complexes of the formulae {[M2(L)]Cl}n and [M(L1)Cl2]n (where M = Co(II), Ni(II) and Cd(II)). A range of techniques were used to confirm the entity of ligands and their complexes. The formation of ligands and mode of complexation and geometrical structure of the title polymeric complexes were verified using FTIR, electronic spectra, NMR, ESMS, magnetic susceptibility, micro-elemental analysis, metal content, chloride content and conductance. The analytical and spectroscopic data indicated the formation of four-coordinate complexes, with a tetrahedral geometry for Co(II) and Cd(II), and square planer for Ni(II) in L- and L1 complexes. Biological evaluation of ligands and their polymeric complexes against gram-positive bacteria (G+), Bacillus stubtili, Staphylococcus aureus, and gram-negative bacteria (G-), Escherichia coli and Pseudomonas aeruginosa, showed ligands and their polymeric metal complexes have a good effect on the screened bacteria. [ABSTRACT FROM AUTHOR]

Complexes of NiII, CuII, ZnII and CdII metal ions with a novel Schiff base ligand 4-(((3-ethyl-5-mercapto-4H-1,2,4-triazol-4-yl)imino)methyl)-2-methoxy-6-nitrophenol (HTNP) were synthesised, thoroughly characterized by spectral techniques i.e. IR, 1H-NMR, fluorescence, electronic spectra and also structurally examined by elemental analysis, thermal analysis and magnetic moment measurements. A significant enhancement in the fluorescence intensity of HTNP was observed after complexation. Comparative in vitro antimicrobial activities of HTNP and its metal complexes were studied and these novel compounds were found to show moderate to significant antibacterial activity. The results also indicated that antimicrobial activity of the Schiff base ligand (HTNP) gets considerably increased on complexation. [ABSTRACT FROM AUTHOR]

The current work deals with the VO(II), Cr (III), Mn(II) complexes which have been made by a new ligand, To classify the three complexes, infrared spectroscopy was used. FTIR, UV SPectroscopy and AtomiC AbSorption Spectrometry were also used to detect the ratio of carbon, hydrogen and nitrogen synthesized and precise materials. There was also a study of the physical properties like Temperature, Color, ElectrIcal Conductivity, and Magnetic characteristics. The ligand preparation was 2: 1, besides, all the synthesized complexes were 8 slanted façades. A theoretic treatment for structural of the (L) and its complexes in gas phase was conducted by using Hyper Chem. 8 program. PM3 Method used calculating the electrostatic potential (EP) and Molecular Orbital Surfaces of the (L). The Heat of Formation (ΔHf), Binding Energy (ΔEb), Total energy (ΔET), Vibration Spectra, and Electronic Spectra for the Ligand (L) and its metal complexes were calculated by PM3 and ZINDO/1 methods. [ABSTRACT FROM AUTHOR]

Phthalonitriles bearing p-cyclohexylphenoxy groups have been obtained on the basis of 4-bromo-5-nitrobenzene-1,2-dicarbonitrile and transformed into the octasubstituted cobalt and copper phthalocyanines. The obtained compounds have been characterized by spectral methods. [ABSTRACT FROM AUTHOR]

The magnetic circular dichroism (MCD) spectra of metal complexes of tetrakis(thiadiazole)porphyrazines ([TTDPzM] with M = 2HI, ZnII, MgII(H2O), and CdII) have been recorded in dimethyl formamide solution. Together with the UV–Vis spectra, the MCD spectra provide useful information about the structure and electronic properties of the complexes. The experimental UV–Vis and MCD spectra compare pretty well with DFT calculations of two sorts, based either on the sum‐over‐states (SOS) approach or on the complex polarization propagator approach. They further corroborate the findings and interpretation of MCD spectra of porphyrazines based on the model of Michl for peripheral molecular orbitals. Magnetic circularly polarized luminescence (MCPL) spectra, quite uncommon in the literature, have been recorded for [TTDPzM] (M = 2HI, ZnII, MgII(H2O)). [ABSTRACT FROM AUTHOR]

A new series of transition‐metal complexes of Schiff base ligand containing the amino mercapto triazole moiety (HL) was prepared. The Schiff base and its metal complexes were elucidated by different spectroscopic techniques (infrared [IR], 1H nuclear magnetic resonance, UV–Visible, mass, and electron spin resonance [ESR]), and magnetic moment and thermal studies. Quantum chemical calculations have been carried out to study the structure of the ligand and some of its complexes. The IR spectra showed that the ligand is chelated with the metal ion in a neutral, tridentate, and bidentate manner using NOS and NO donors in complexes 1–6, 10–12, and 7 and 8, respectively, whereas it behaves in a monobasic tridentate fashion using NOS donor sites in copper(II) nitrate complex (9). The magnetic moment and electronic spectra data revealed octahedral and square pyramidal geometries for complexes 2, 11, 12, and 5–8 and 10, respectively. However, the other complexes were found to have tetrahedral (4), trigonal bipyramidal (1 and 3), and square planar (9) structures. Thermal studies revealed that the chelates with different crystallized solvents undergo different types of interactions and the decomposition pathway ended with the formation of metal oxygen (MO) and metal sulfur (MS) as final products. The ESR spectrum of copper(II) complex 10 is axial in nature with hyperfine splitting with 2B1g as a ground state. By contrast, complexes 7 and 8 undergo distortion around the Cu(II) center, affording rhombic ESR spectra. The HL ligand and some of its complexes were screened against two bacterial species. Data showed that complex 12 demonstrated a better antibacterial activity than HL ligand and other chelates. [ABSTRACT FROM AUTHOR]

Background: Enforcement of sustainable and green chemistry protocols has seen colossal surge in recent times, the development of an effective, eco-friendly, simple and novel methodologies towards the synthesis of valuable synthetic scaffolds and drug intermediates. Recent advances in technology have now a more efficient means of heating reactions that made microwave energy. Efforts to synthesize novel heterocyclic molecules of biological importance are in continuation. Microwave irradiation is well known to promote the synthesis of a variety of organic and inorganic compounds. The aim of current study was to conceivea mild base mediated preparation of novel Schiff base of 2-Acetylpheno with trimethoprim drug (H2TPBD) and its complexes with Cu(II),Co(II),Zn(II),Cd(II) and Ni(II). Method: The products are likening with traditional processes for reaction time and their yield. (H2TPBD) and the complexes were diagnosed by spectroscopic (Mass, NMR, UV–vis, IR spectral studies, analytical and magnetic data. Results: All complexes were found to be six co-ordinate mono-hydrate as[M(TPBD)(H2O)] [1:1(ligand:metal) ratio] type. The complexes exhibited biological activity against (B.subtilis, P.aeruginosa, C.albicansand Staphylococcus aureus) bacterial strains as compared to (H2TPBD). The antibacterial efficiency showed the following trend: M(II)-complexes ˃ (H2TPBD) ˃ parent drugs. Cu(II), Co(II), Zn(II), Cd(II)andNi(II) complexes had good antioxidant efficiencies than the free ligand (H2TPBD). DNA binding study of complexes with (CT)-DNA utilizing binding nature of the complexes with CT DNA has moreover inveterate by viscometer and emission which then bespoken that complexes bound with CT DNA. The complexestook effective scavenging impact during the DPPH process. Conclusion: [H2TPBD] has been prepared by the condensation of trimethoprim drug and Acetylphenol and characterized by electronic absorption spectra, ¹H and 13C-NMR and IR,mass UV-spectroscopies. [ABSTRACT FROM AUTHOR]

To improve biological activity of chitosans, new Zn(II), Pd(II) and Pt(II) complexes with biopolymeric amphiphilic Schiff bases anchored in different molecular weight chitosans matrices modified with salicylaldehyde and glycidol were prepared. Salicylaldehyde was introduced to generate complexing Schiff base sites in the chitosans matrix while glycidol is intended to increase the water solubility of the resulting biopolymeric complexes. These novel complexes were characterized using various techniques and assayed for antimicrobial and antitumor activity. The effectiveness of modification was evaluated using FTIR spectroscopy, and thermal behavior of the complexes by TG/DTG-DTA. XPRD showed that the crystallinity of the ligand diminished after the metal complexation. Surface morphologies, investigated by SEM, revealed that the complexes are rougher than chitosan matrix, and the presence of metallic ions was confirmed by EDX. Electronic spectra suggested square planar geometry for Pd(II) and Pt(II) complexes. Concerning antimicrobial activity, the novel complexes exhibited higher antibacterial efficiency against Pseudomonas syringae than against the Fusarium graminearum fungi regarding the free ligand. Complexes also exhibited high antitumor effects against the MCF-7 breast cancer cells, with certain selectivity regarding non-tumor cells (Balb/C 3T3 clone A31) depending on concentration and molar mass, indicating that they could potentially be used for antitumor applications. • Biopolymeric amphiphilic Schiff base complexes with potential biological activity were prepared. • These novel complexes were characterized and assayed for antimicrobial and antitumor activity. • Electronic spectra suggested square planar geometry for Pd(II) and Pt(II) complexes. • Complexes exhibited higher antibacterial than antifungal efficiency regarding the free ligands. • They exhibited antitumor action against MCF-7 cells with selectivity to Balb/C 3T3 cells. [ABSTRACT FROM AUTHOR]

1‐Heteroaryl‐substituted benzotriazole motifs represent a new class of bidentate chelating ligands for several transition metals. Although metal complexes having such ligands in tris‐ and bis‐chelated binding have been extensively studied, investigation of mono‐chelated metal complexes, especially their structural and catalytic properties, is rarely explored. In this work, two such complexes – [(para‐cymene)Ru(BTZ‐2P)Cl]PF6 and [(para‐cymene)Ru(BTZ‐2Q)Cl]PF6, (BTZ‐2P=1‐(pyridine‐2‐yl)‐1H‐benzo[d][1,2,3]triazole; BTZ‐2Q=1‐(quinoline‐2‐yl)‐1H‐benzo[d][1,2,3]triazole) have been synthesized and characterized through various spectroscopic method and X‐ray crystallography. Their electronic spectra and electrochemical properties have also been explored. Both the complexes have been successfully applied in two types of important catalytic processes – (a) oxidation of aryl olefins to corresponding aromatic carbonyl compounds, and (b) transfer hydrogenation of aromatic carbonyl compounds to the corresponding alcohols. [ABSTRACT FROM AUTHOR]

In this novel paper, we synthesized binuclear complexes of metal chloride of Cu(II), Ni(II) with organic compounds 3,3'-dihydroxy benzidiene and 2-amino thiophenol. The type of complex is [LM2Cl4]. The characterization had been found from elemental analysis, molar conductivity, Infrared, Ultraviolet-visible, cyclic voltammetry, TG-DTA, magnetic measurements, DNA cleavage study and antimicrobial study. The elemental analysis suggested that the metal-ligand ratio is 2:1. The microbes Escherichia coli, Klebsiella pneumonia and Staphylococcus aureus were used to find out antimicrobial activity of binuclear metal complexes. [ABSTRACT FROM AUTHOR]

Glyoxylic acid and ethyl carbazate condense in situ in the reaction medium and react with metal nitrates of Co, Ni or Cu to yield isostructural metal complexes with the general formula [M(gly-ec)2(H2O)2] (M = Co2+ (1), Ni2+ (2) and Cu2+ (3); Hgly-ec = ethoxycarbonyl-hydrazono-acetic acid). These products are elucidated through various physicochemical techniques including powder and single-crystal X-ray diffraction. X-ray crystallography of complexes 1 and 3 reveals that two anionic Schiff base ligands are coordinated to the metal ion via (N, O) bidentate chelation and situated trans to each other in equatorial positions and are nearly coplanar with the metal atom. The two coordinated water molecules occupy the trans axial positions, with a slightly distorted octahedral geometry. The thermal behavior of complexes 1–3 is studied in air and nitrogen atmosphere from 30 to 800 °C. In both mediums, all of the complexes show endothermic followed by exothermic decomposition to yield metal oxides as the end products at low temperature. Hence, these isotypic complexes may be used as solid-state precursors for the preparation of respective metal oxides due to their low temperatures of decomposition. [ABSTRACT FROM AUTHOR]

Metallization of 2,9,16,23-tetra-tert-butyl-3,10,17,24-tetranitrophthalocyanine or template condensation of 4-tert-butyl-5-nitrophthalodinitrile with chlorides of some lanthanides furnished the corresponding metal complexes. Their spectral properties were studied. [ABSTRACT FROM AUTHOR]

The thiocarbohydrazone Schiff base ligand (LH2) was synthesized by the condensation of thiocarbohydrazide and 1-(5-bromo-2-hydroxyphenyl)ethanone. Such Schiff base ligand with heteroatoms such as nitrogen, oxygen and sulphur as donor atoms have unique tendency to conjugate with metal ion for the formation of metal complexes. By knowing this fact, a series of Cu(II), Co(II), Th(IV), and Zr(IV) metal complexes were synthesized from (H2L) Schiff base ligand and characterized by using spectroscopic techniques. IR spectra reveal that co-ordination of the ligand with metal ion resulting into mononuclear complexes. The ligand mainly coordinates through the hydroxyl oxygen and azomethine nitrogen to give five membered rings in some cases. Molar conductance values of synthesized metal complexes in DMF indicate the nonelectrolytic nature of the complexes. From the observed magnetic moment and electronic spectral data, probable structures for the complexes have been proposed. The thermal behavior of ligand and metal complexes shows the presence of lattice and the co-ordinate water around their co-ordination sphere. The synthesized Schiff base ligand and its complexes were also tested for their antimicrobial activity against E. Coli, S. aureus, S. epidermis, and K. pneumoniae. [ABSTRACT FROM AUTHOR]

DFT/B3LYP calculations with full geometry optimizations have been carried out on 1-phenylazo-2-naphthol and their metal complexes of formula M(MePhNap)2 (M = Ni, Pd, Pt, Cu, Ag, and MePhNap = 1-(− 4-methylphenylazo)-2-naphtol) in their neutral, oxidized, and reduced forms. The predicted structures provide to the M(II) metal ions the square planar geometry and distorted azo ligand. The TD-DFT theoretical study performed on the optimized geometry allowed us to predict the UV–Vis spectra and to identify quite clearly the spectral position and the nature of the different electronic transitions according to their molecular orbital localization. Large HOMO-LUMO gaps are calculated for all optimized structures suggesting good chemical stabilities, hence, reproducing the available UV–Vis spectra and compared to that of free ligand. The electronic spectra obtained in DMSO and ethanol polar solvents predict more important red shifts than those obtained in hexane as nonpolar one. [ABSTRACT FROM AUTHOR]

A novel Schiff base (L) and its Pd(II) and Pt(II) complexes were synthesized. The Schiff base was prepared by condensation of 6- tert -butyl 3-ethyl 2-amino-4,5-dihydrothieno[2,3- c ]pyridine-3,6(7H)-dicarboxylate with 2,3,4-trimethoxybenzaldehyde. The ligand and its metal complexes were characterized via spectroscopic data i.e. proton and carbon NMR, electronic spectra, FT-IR, LC-MS, as well as melting point, micro analysis, magnetic measurement, molar conductance, and thermogravimetric analysis. The ligand acted as a bidentate molecule coordinating through NO heteroatoms to Pd(II) and Pt(II) metal ions. The geometric structures of Pd(II) and Pt(II) complexes were determined as square-planar. Electronic and photonics properties of metal(II) complexes were investigated under different conditions. Although the optical band gap and refractive index values of the ligand are close to the limit values of the semiconductor, it appears to be an ideal material especially for the semiconductor-insulator region of electronic and optoelectronic devices. [Display omitted] • Schiff base ligand and its Pd(II) and Pt(II) complexes were prepared and characterized. • Electronic and photonics properties of metal complexes were investigated. • Compounds can be used in the production of non-high efficiency electronic and photonic devices. [ABSTRACT FROM AUTHOR]

• Ultrasonic reaction methodused to synthesis of Zn and Pd complexes. • DMB forms coordination bonds through both oxygen atoms at 1:2 ratio. • Enhanced anticancer activity: Zinc and palladium complexes surpass 5FU. • IC50 of Zn complex against colon and breast cancer was 1.36 and 2.12 µg/mL • IC50 of Pd complex against colon and breast cancer was 32.7 and 1.89 µg/mL. In this work, we present a thorough investigation encompassing various aspects of zinc and palladium complexes synthesized with 2, 6-dimethoxybenzoic acid. The complexes were prepared through an ultrasonic reaction, offering a rapid, cost-effective, and environmentally friendly method. Characterization of the complexes, prepared in a 1:2 metal-to-ligand ratio, was carried out using elemental analysis, infrared spectra, proton nuclear magnetic resonance, molar conductivity, and melting point measurements. The results revealed that the ligand exhibited chelating bidentate behavior, forming coordination bonds through both oxygen atoms of the carbonyl group. The prepared complexes were evaluated for their anticancer activity against breast cancer and colon cancer cell lines. Remarkably, the complexes exhibited significantly higher cancer cell-killing potential compared to the commonly used drug 5-fluorouracil, with cell death rates reaching 99% for both complexes. To gain insights into the underlying mechanisms of this enhanced anticancer activity, molecular docking studies were conducted, revealing a binding energy of no more than -9.14 kcal/mol between the complexes and the amino acids of the cancer cells. Furthermore, theoretical studies employing Density Functional Theory (DFT) were performed to provide additional diagnostic insights. These studies encompassed molecular structural analysis, computational vibrational properties, natural bond orbital analysis (NBO) and FMOs, electronic properties (UV–Vis spectra), average local ionization energy (ALIE), electrostatic potential (ESP), electron localization function (ELF), and reduced density gradient (RDG/NCI) analyses. The comprehensive investigation presented in this study sheds light on the synthesis, characterization, theoretical analysis, and remarkable anticancer potential of zinc and palladium complexes with 2,6-dimethoxybenzoic acid. [ABSTRACT FROM AUTHOR]