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The series of Schiff base ligands, N'‐(pyridine‐2‐ylmethylene)isonicotinohydrazide (I), N'‐(pyridine‐3‐ylmethylene)isonicotinohydrazide (II) and N'‐(pyridine‐4‐ylmethylene)isonicotinohydrazide (III), and the Zn(II) complexes of the ligands (I and II), [N'‐(pyridine‐2‐ylmethylene)isonicotinohydrazide]‐trichlorozincoate (IV) and [N'‐(Pyridin‐3‐ylmethylene) isonicotinohydrazide] trichlorozincoate (V) have been newly synthesized and their structures have been characterized by 1H, 13C NMR and FT‐IR spectroscopies, elemental analysis and single crystal X‐ray diffraction technique. The Hirshfeld surface analyses have been confirmed the importance of H‐atom contacts in establishing the packings. The ground state equilibrium geometries of the synthesized compounds are optimized at DFT/B3LYP/6‐311++G (d, p) and HF/6‐311++G (d, p) levels of theory (for the ligands) and B3LYP/GENECP method is used as the mixed basis sets of LANL2DZ (for Zn) and 6–311G (for other atoms) in the gas‐phase. The structural parameters obtained from the theoretical studies of the compounds are compared with their experimental ones. Their linear and nonlinear optical (NLO) properties are also calculated by the same methods. In the ground state, the energy band gaps (Eg) of the Schiff bases (I, II and III) have been calculated as 4.38 eV, 4.36 eV and 4.46 eV (at B3LYP) and 9.94 eV, 9.81 eV and 10.20 eV (at HF), respectively. [ABSTRACT FROM AUTHOR]

This study aimed to achieve enzyme mediated green synthesis of Zinc oxide nanoparticles and its antibacterial, antioxidant and anticancer activities using the leaf of Ipomea pes-caprae. The enzymes present in the leaf of Ipomea pescaprae were extracted and the extract obtained was subjected to GC-MS for the determination of bioactive compounds and thereby synthesized the zinc oxide nanoparticle using the extracted enzymes and studied their biological properties. The GCMS analysis of the I. pes-caprea leaf enzymes extract revealed the presence of 14 bioactive compounds with valuable biological activities. The major chemical constituents are n-Hexadecanoic acid, l-(+)-Ascorbic acid 2,6-dihexadecanoate, Tridecanoic acid, Methyl 8,11,14-heptadecatrienoate, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-, 2-Pyridinamine, N-(4,5-dihydro-5-methyl-2-thiazolyl)-3-methyl-,tert-Butyl(5-isopropyl-2methylphenoxy)dimethyl silane, 5-Acetamido-4,7-dioxo-4,7-dihydrobenzofurazan, Ethyl2-(2-chloroacetamido)-3,3,3-trifluoro-2-(4fluoroanilino) propionate, Benzo[h]quinoline, 2,4-dimethyl-, 1H-Indole, 1-methyl-2-phenyl-, 1,3-Benzodioxole, 5-(2-nitro-1-propenyl)-, Anthracene, 9,10-dihydro-9,9,10-trimethyl-. The enzymes extract supported the synthesis of zinc oxide nanoparticles and showed very good biological properties. The presence of various bioactive compounds in the enzyme-mediated synthesis of zinc oxide nanoparticles from the leaf of I. pes-caprea proved many medical importance. It can be concluded that the investigation has opened up an important perspective in pharmaceutical research and plant enzymes can be used for the development of potential, novel antioxidant and anticancer agents for the treatment of many diseases. [ABSTRACT FROM AUTHOR]

The ligand design factors that may influence the isolation of metallosupramolecular helicates or mesocates still deserve to be investigated. In this sense, dinuclear nickel(II), copper(II) and zinc(II) compounds were obtained by electrochemical synthesis using a family of five Schiff base ligands, H2Ln (n = 1–5), derived from bisphenylmethane and functionalized with bulky tert-butyl groups in the periphery and ethyl groups in the spacer. Six of the new complexes were characterized by X-ray crystallography, thus demonstrating that the helicate structure is predominant in the solid state. 1H NMR studies were performed for the zinc complexes to analyze if the helical architecture of the metal complexes is retained in solution. These studies reveal that the presence of a tert-butyl group in the ortho position with respect to the OH group is an essential factor identified for the existence of a helicate conformation in solution. [ABSTRACT FROM AUTHOR]

Advancing the use of alkali‐metal alkoxides as additives to activate organometallic reagents, here we report the synthesis and characterization of a novel potassium zincate [{(PMDETA)KZn(OtBu)Et2}2] obtained by co‐complexation of equimolar amounts of potassium tert‐butoxide, diethyl zinc and the tridentate donor PMDETA (N,N,N',N",N"‐pentamethyldiethylenetriamine). Demonstrating its ability to activate both of the Et groups towards alkyne C−H metalation, this zincate reacts at room temperature with 2 equivalents of phenylacetylene to furnish [(THF)2KZn(CCPh)2(OtBu)}2], whereas, for the homometallic [ZnEt2(TMEDA)] (TMEDA=N,N,N',N'‐tetramethylethylendiamine) only one Et group is reactive towards the same substrate under the same conditions. Investigations on the reactivity of these complexes to undergo N−H amine metalation using 2, 6‐diisopropylphenylamine (NH2Dipp) and 1,2,3,4‐tetrahydroquinoline (THQ(H)) as model substrates revealed that while homometallic [ZnEt2(TMEDA)] is completely inert towards these amines, heterobimetallic [{(PMDETA)KZn(OtBu)Et2}2] reacts through one of its Et groups to form [(THF)2KZn(OtBu)(Et)(NHDipp)] as well as [(THF)4K2Zn(THQ)4]. The latter is obtained as a side product of ligand redistribution of a putative [(THF)nKZn(OtBu)(Et)(THQ)] intermediate. An alternative method to access mixed amide/alkoxide potassium zincates is also described by assessing the co‐complexation of KOtBu with Zn(HMDS)2 in the presence of PMDETA which gave [(PMDETA)KZn(HMDS)2(OtBu)]. [ABSTRACT FROM AUTHOR]

Mono-, di-, and trifluorophenyl substituted in different positions of amine fragments bis [2-[[(E)-((fluorophenyl)iminomethyl]-N-(p-tolylsulfonyl)anilino]zinc(II) complexes were synthesized. Their crystal structure, photo- and electroluminescent properties, and protistocidal, fungistatic, and antibacterial activities were studied. It has been shown that the introduction of fluorine atoms and an increase in their number in the ligand structure of the resulting metal complexes promote the luminescence quantum yields and values of performance and brightness in EL cells compared to their previously studied chlorine-substituted analogs. [ABSTRACT FROM AUTHOR]

[Display omitted] The two-step synthesis of porphyrin derivatives, exhaustively bbb-substituted at the 'Eastern half', starting from meso- tetraarylporphyrin chelates (Cuii, Znii, Niii) upon their reaction with nitric acid, is described. The intermediates obtained (mainly dinitro-derivatives) in the reaction with carbanions bearing a leaving group X at the reactive centre give tetrasubstituted at the bbb-positions products, the ones of vicarious nucleophilic substitution of hydrogen. The products seem to be potential anticancer PDT agents, practically unavailable by other methods. [ABSTRACT FROM AUTHOR]

In this study, we report the design, synthesis, and catalytic application of the novel nitrogen-rich Zn(II) MOF [Zn2(μ3-1κN,2κN′,3κO-HL)2(DMF)2]n·nH2O (HL2− = 4-((4-(1H-tetrazol-5-yl)phenyl)carbamoyl)benzoate), denoted as ZnMOF, for the efficient conversion of carbon dioxide (CO2) to cyclic carbonates via cycloaddition with epoxides. It was synthesised from a tetrazole appended amide-functionalised pro-ligand (H3L) and Zn(NO3)2·6H2O under hydrothermal conditions. The synthesised material was characterised namely by elemental analysis, infrared spectroscopy, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction analyses. The catalytic potential of ZnMOF was investigated in the CO2 cycloaddition reaction with various epoxides, with conversions ranging from 17% to 99%. The catalyst retained its activity across multiple reaction cycles, demonstrating its stability and reusability. The influence of co-catalysts on the reaction was explored, with tetrabutylammonium bromide (TBABr) emerging as the most effective one. A plausible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis and characterization of a mononuclear zinc complex (1) containing a redox-active bis(4-antipyrinyl) derivative of the 3-cyanoformazanate ligand. Complex 1 was readily obtained by refluxing zinc acetate with 3-cyano-1,5-(4-antipyrinyl)formazan (LH) in a methanolic solution. Single-crystal X-ray diffraction analysis of complex 1 shows that the formazanate ligands bind to the zinc center in a five-member chelate "open" form via the 1- and 4-positions of the 1,2,4,5-tetraazapentadienyl formazanate backbone leading to the formation of the mononuclear bis(formazanate) zinc complex exhibiting a distorted octahedral geometry. We also report the study of resistive-switching random access memory application of this solution-processable bis(formazanate) Zn(II) complex to facilitate the practical implementation of transition metal complex-based molecular memory devices. The complex demonstrated high conductance switching with a large ON–OFF ratio, good stability, and a long retention time. A trap-controlled space charge limited current mechanism is proposed for the observed resistive switching behavior of the device, wherein the role played by the [ZnIIL2] complex that comprises the extended redox-active conjugated ligand backbone is revealed by corroborating electrochemical studies, spectrochemical experiments, and DFT calculations. In addition to providing significant insights into the molecular design of transition metal complexes for memory applications, this study also presents the utilization of ZnIIL2 towards the realization of non-volatile resistive random access memory (RRAM) devices with inorganic/organic hybrid active layers that are highly cost-effective and sustainable. These devices exhibited multilevel switching and low current operation, both of which are desirable for advanced memory applications. [ABSTRACT FROM AUTHOR]

An octahedral complex of Zn(II) with a ligand from a class of pyridine- based 1,3-selenazolyl-hydrazones was synthesized and characterized by IR and NMR spectroscopy and single crystal X-ray diffraction analysis. The purity of the complex was confirmed by elemental analysis. Two ligands are coordinated in the neutral NNN-tridentate form forming a complex cation, while the positive charge is neutralized by [ZnCl4]2-. Complex crystallizes in monoclinic C2/c space group with the Zn atoms situated in a special position. The packing features of the novel complex were analyzed using Hirshfeld surfaces, construction of 2D pseudosymmetric plot and DFT quantum mechanical calculations and compared with the previously published sulfur-based isostere. The key difference in the structures, imposed by replacement of sulfur with selenium, were identified. [ABSTRACT FROM AUTHOR]

Two new Zn(II) complexes bearing tridentate hydrazone‐based ligands with NNO or NNS donor atoms were synthesised and characterised by elemental analysis, infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies, and single crystal X‐ray diffraction methods. These complexes, together with four previously synthesised analogues, having hydrazone ligands with a NNO donor set of atoms, were successfully employed as catalysts in the ketone‐amine‐alkyne (KA2) coupling reaction, furnishing tetrasubstituted propargylamines, compounds with unique applications in organic chemistry. DFT calculations at the CAM‐B3LYP/TZP level of theory were performed to elucidate the electronic structure of the investigated Zn(II) complexes, excellently correlating the structure of the complexes to their catalytic reactivity. [ABSTRACT FROM AUTHOR]

Tuberculosis disease is a serious threat to humans and spreading quickly worldwide, therefore, to find a potent drug, the synthesis of hydrazone ligands endowed Co(II), Ni(II), Cu(II), Zn(II) metal complexes were carried out and well characterized by numerous spectral and analytical techniques. The octahedral geometry of the complexes was confirmed by spectral analysis. Further, in vitro antituberculosis efficacy of the compounds (1–10) revealed that complexes (6), (9), (10) have highest potency to control TB malformation with 0.0028 ± 0.0013–0.0063 ± 0.0013 µmol/mL MIC value while Zn(II) complex (10) (0.0028 ± 0.0013 µmol/mL) has nearly four time potent to suppress TB disease in comparison of streptomycin (0.0107 ± 0.0011 µmol/mL). The antimicrobial and anti-inflammatory evaluations revealed that the complex (10) is more active with lowest MIC (0.0057–0.0114 µmol/mL) and IC50 (7.14 ± 0.05 µM) values, correspondingly which are comparable with their respective standard drugs. Furthermore, the theoretical studies such as molecular docking, DFT, MESP and ADMET were employed to authenticate the potency of HL2 hydrazone ligand (2) and its metal complexes (7–10) which revealed that the zinc(II) complex (10) might be utilized as novel drug candidate for tuberculosis dysfunctions. So, the present research gives a new insight for in vivo investigation of the compounds. [ABSTRACT FROM AUTHOR]

We report the synthesis of cyclometalated monoaryl MnIII fluoro complexes using bis(trifluoromethyl)zinc reagent, Zn(CF3)2(DMPU)2, under mild conditions via a reaction pathway that involves initial transmetalation followed by α‐fluorine elimination. The formation of difluorocarbene in these reactions was detected by trapping experiments. Such facile difluorocarbene generation from MnIII results in moderate enhancement of difluoropropanation and difluoropropenation of alkenes and alkynes using Zn(CF3)2(DMPU)2 at lower temperature (20–60 °C) and short reaction time, suggesting potential application of manganese(III) perfluoroalkyl complexes as reactive species for carbene transfer reactivity. [ABSTRACT FROM AUTHOR]

Three zinc(II) complexes, [ZnL(μ1,5-dca)]n·nCH3OH (1), [ZnI2(HL)]·CH3OH (2), and [Zn(NCS)4]·2H2L (3), where L, HL and H2L are the monoanionic, zwitterionic, and monocationic forms of the Schiff base 1-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)naphthalen-2-ol, dca is dicyanamide, have been successfully synthesized and with their components and structures characterized by CHN elemental analyses, infrared and electronic spectroscopy. The detailed structures are further confirmed by single crystal X-ray determination. The Zn atom in the polymeric complex 1 is in square pyramidal coordination, with the phenolate O, imino N and pyrrolidine N atoms of the Schiff base, and one terminal N atom of dca ligand in the basal plane, and with the other terminal N atom of dca ligand at the apical position. The Zn atom in the mononuclear complex 2 is coordinated by the imino N and phenolate O atoms of the Schiff base, and two iodide ligands, forming tetrahedral coordination. The Zn atom in the mononuclear complex 3 is coordinated by four N atoms from four thiocyanate ligands, forming tetrahedral coordination. The Schiff base and their three metal complexes have been tested for their Jack bean urease activity. As a result, complex 2 has the most activity (IC50 = 3.2±1.1 μmol/L). [ABSTRACT FROM AUTHOR]

The title compound, [Zn(C20H18BN2)2] (ZnL2), is an overall uncharged chelate that consists of two units of an NH-deprotonated 10-aza-9-borabenzo[h] quinoline ligand (L) per ZnII center. It was synthesized in two steps by treating the protonated ligand HL with lithium bis(trimethylsilyl)amide and further conversion with diethylzinc. Its asymmetric unit comprises one ZnL fragment; the molecule is completed by application of inversion symmetry at Zn. Due to the fourfold coordination with nitrogen atoms, the zinc(II) ion is located in a distorted tetrahedral environment. Besides the relatively short N--Zn bonds, ZnL2 is characterized by the significant protrusion of the central ion from the plane of the ligand backbone. The crystal structure is consolidated by intra- and intermolecular π-π stacking interactions, while the polarized B--N bond is barely involved in any close atom contacts. [ABSTRACT FROM AUTHOR]

We report the synthesis, crystal structure, and characterisation of a dinuclear Co(II) compound with thiodiacetate (tda) and phenanthroline (phen) as ligands (1), and of a series of metal complexes isomorphous to 1 with different Co : Zn ratios (2, 4 : 1; 3, 1 : 1; 4, 1 : 4; 5, 1 : 10). General characterisation methodologies and X-ray data showed that all the synthesised complexes are isomorphous to Zn(II) and Cu(II) analogues (CSD codes: DUHXEL and BEBQII). 1 consists of centrosymmetric Co(II) ion dimers in which the ions are 3.214 Å apart, linked by two μ-O bridges. Each cobalt atom is in a distorted octahedral environment of the N2O3S type. UV–vis spectra of 1 and 5 are in line with high spin (S = 3/2) Co(II) ions in octahedral coordination and indicate that the electronic structure of both Co(II) ions in the dinuclear unit does not significantly change relative to that of the magnetically isolated Co(II) ion. EPR spectra of powder samples of 5 (Co : Zn ratio of 1 : 10) together with spectral simulation indicated high spin Co(II) ions with high rhombic distortion of the zfs [E/D = 0.31(1), D > 0]. DC magnetic susceptibility experiments on 1 and analysis of the data constraining the E/D value obtained by EPR yielded g = 2.595(7), ‖D‖ = 61(1) cm−1, and an intradimer ferromagnetic exchange coupling of J = 1.39(4) cm−1. EPR spectra as a function of Co : Zn ratio for both powder and single crystal samples confirmed that they result from two effective S′ = 1/2 spins that interact through dipolar and isotropic exchange interactions to yield magnetically isolated S′ = 1 centres and that interdimeric exchange interactions, putatively mediated by hydrophobic interactions between phen moieties, are negligible. The latter observation contrasts with that observed in the Cu(II) analogue, where a transition from S = 1 to S′ = 1/2 was observed. Computational calculations indicated that the absence of the interdimeric exchange interaction in 1 is due to a lower Co(II) ion spin density delocalisation towards the metal ligands. [ABSTRACT FROM AUTHOR]

Removal of organic contaminants such as azo dyes is highly desirable from the industrial waste waters because of their toxicity, stability, and mutagenic properties. Herein, the nano‐composite CuO@Zn−2‐PTZ has been synthesized by a simple hydrothermal method and characterized by a combination of techniques like Powder X‐Ray Diffraction (PXRD), UV‐Visible spectroscopy, Fourier Transform Infrared (FT‐IR) spectroscopy, Scanning Electron Microscopy‐Energy Dispersive X‐ray analysis (SEM‐EDX) etc. The band gap of the composite was found to be 2.07 eV, indicating the spread of absorption in to the visible region in comparison to the high (3.76 eV) band gap of the parent metal organic framework (MOF) Zn−2‐PTZ. The composite CuO@Zn−2‐PTZ exhibited much higher photo degradations, under natural sunlight, towards the decompositions of the cationic [Methylene Blue (MB)] and anionic [Methyl Orange (MO)] dyes as well as mixed MB and MO dyes taken in water. A comparative study was also undertaken by taking CuO nanoparticles and the parent MOF separately with the same set of dyes under same conditions to substantiate the above. The enhancement of photo‐catalytic activity has been caused by the formation of a p‐n hetero‐junction in the composite. The Langmuir‐Hinshelwood model showed that the degradation rates of the dyes follow pseudo‐first‐order kinetics. [ABSTRACT FROM AUTHOR]

A simple and efficient fluorescent probe (E)-4-bromo-2-((((5-methylfuran-2-yl)methyl)imino)methyl)phenol (BFMP) for the detection of Zn2+ ions was synthesized by the condensation of 5-methyl-furfurylamine and 5-bromosalicylaldehyde. Elemental analysis, LC-MS, ATR-IR spectroscopy, and NMR (1H and 13C) spectroscopy were performed to confirm the structures of the Schiff base ligand and its Zn(II) complex. Further, the molecular structure of BFMP was confirmed by single-crystal XRD. It is noteworthy that BFMP displayed favourable behaviour of the florescent active molecule. The BFMP solution was yellow, which after the addition of the Zn2+ solution became colourless, as observed by the naked eye. Moreover, under ultraviolet (UV) radiation, a maximum absorption at 425 nm and a large fluorescence enhancement at 560 nm were observed. BFMP was very selective to Zn2+ ions, even in the presence of other metal ions. This includes Cd2+, which has a binding constant (Ka) of 1.74 × 106 M−1, and a detection limit of this finding suggested that a fluorescence probe (BFMP) can be used to detect Zn2+ by colorimetric detection. The detection limit can reach up to 0.249 × 106 M−1. Furthermore, the efficiency of the ligand was tested using real water samples (lake and tap water), and the results revealed that BFMP acted more efficiently in both the tested water samples. The geometries of BFMP and BFMP–Zn2+ were investigated by the density functional theory (DFT) method using the B3LYP method with 6-311++G(d,p) and LAN2LZ basis sets, respectively. The optimized geometrical parameters obtained by the DFT calculation are in good agreement with the X-ray crystal structure data. [ABSTRACT FROM AUTHOR]

New complexes CuCl2[AbAc]2 (I), CoCl2[AbAc]2 (II), and ZnCl2[AbAc]2 (III) with abiraterone acetate (AbAc) are synthesized. The molecular structure of complex II is determined by X-ray diffraction (XRD) (CIF file CCDC no. 2252346). The cobalt atom coordinates with abiraterone acetate due to the N‑donor pyridine atom. The model processes of hydrolysis of the compounds in acidic and neutral media and their ability to interact with the superoxide radical anion generated in the xanthine–xanthine oxidase enzymatic system are studied. A high activity of complexes I and II is found. The MTT test shows that the antiproliferative activity of compounds I–III against the HCT-116, MCF-7, A-549, and WI-38 cells is comparable with the activity of cisplatin and exceeds that of the initial AbAc for the PC-3 cell line. Complex II also induces cell cycle arrest in the G0/G1 phase of RNA protein synthesis. [ABSTRACT FROM AUTHOR]

The complex [Zn(Phen)(H2O)L2] (I), where HL is 5-benzyltetrazole, Phen is 1,10-phenanthroline, was synthesized. The compound was characterized by standard physicochemical methods (elemental analysis, powder X-ray diffraction, IR spectroscopy). According to X-ray diffraction data (CCDC no. 2220597), zinc coordination environment in the crystal structure of I corresponds to a distorted trigonal bipyramid. The ligand HL is monodentate and is coordinated via tetrazolate ring nitrogen. The stability of complex I was studied by NMR spectroscopy in DMSO. The cytotoxic properties of the compound were assessed against HepG-2 (hepatocellular carcinoma) and MRC-5 (noncancerous human fibroblasts) cells. Complex I exhibits weak cytotoxic properties in the studied concentration range (1–100 µM). [ABSTRACT FROM AUTHOR]

The discovery of new coordination compounds with anticancer properties is an active field of research due to the severe side effects of platinum-based compounds currently used in chemotherapy. In the search for new agents for the treatment of cancer, unsymmetrical N2O2-tetradentate ligand (H2L1 and H2L2) and their Ni(II) and Zn(II) asymmetric complexes (NiII-L1–2 and ZnII-L1–2) have been synthesized and fully characterized. 1H NMR studies revealed that the ligands and complexes were stable in mixtures of DMSO : D2O (9 : 1). Complementary UV-Vis studies confirmed that ZnII derivatives also exhibit high stability in mixtures DMSO : buffer (6 : 4) after 24 h. Single-crystal X-ray diffraction studies confirmed the molecular structures of H2L1, H2L2, NiII-L1, and NiII-L2. At the molecular level, complexes were completely planar without significant distortions of the square-planar geometry according to τ4 parameter. Furthermore, the crystalline structures revealed non-classical intermolecular interactions of the C–H⋯O and the Ni⋯Ni type. The ligands and complexes were screened against the human osteosarcoma (MG-63), human colon cancer (HCT-116), breast cancer (MDA-MB-231) cell lines, and non-cancerous cells (L929). H2L1 and H2L2 ligands not caused cytotoxic effects at a concentration of 100 μM, while NiII-L2, ZnII-L1, and ZnII-L2 complexes induce cytotoxic effects in all cell lines. NiII-L2 was a more active complex against MG-63 (3.9 ± 1.5) and HCT-116 (3.4 ± 1.7) cell lines with IC50 values in the low micromolar range. In addition, this compound was 10-, 5-, and 11-fold more potent than cisplatin in MG-63 (39 ± 1.8), HCT-116 (17.2), and MDA-MB-231 (131 ± 18), respectively. Three complexes exhibited great selectivity for tumoral cells with SI values ranging from 1.6 to 7.4. [ABSTRACT FROM AUTHOR]

Zinc(II) complexes bearing bis(β‐diketiminate) ligands with various linker groups and terminal substituents have been synthesized by deprotonation of the related bis(β‐diketimine)s with zinc(II) bis[bis(trimethylsilylamide)] and diethyl zinc, respectively. One mononuclear and seven dinuclear zinc(II) complexes could be isolated and fully characterized; their solid‐state structures have been determined by means of single‐crystal X‐ray diffraction analysis. Oxygenation experiments of selected dinuclear ethyl zinc bis(β‐diketiminate) complexes afforded a series of novel heteroleptic zinc alkoxide, hydroxide, carbonate, and carboxylate complexes. These findings do not only illustrate the complexity of both the oxygenation of organozinc compounds and the transformation pathways of the thus formed compounds but highlight also the impact of the reaction conditions and variations in the ligand framework. [ABSTRACT FROM AUTHOR]

The negative environmental and human health challenges posed by sulfur oxides that are released upon combustion of fuel oils containing sulfur necessitate the development of methods for its removal, and hydroprocessing is the conventional technique. However, dibenzothiophene and its substituted derivatives are refractory. As such, the coordination polymers (CPs): [Co(tmdp)4Cl2]n1 and [Zn(tpa)2(tmdp)2·(H2O)2]n2, where tmdp is trimethylenedipyridine and tpa is terephthalic acid, were synthesized for application in adsorptive separation to selectively remove the refractory compounds. Spectroscopy techniques (UV-vis and FT-IR), single crystal XRD, micro-elemental analysis, TGA and SEM were used for characterization. Heat activation of both CPs was carried out to remove lattice solvent molecules before applying them in adsorption. Both CPs, showed good adsorption of dibenzothiophene (DBT) with maximum adsorption capacities of 49 mg g−1 and 44 mg g−1, respectively. The adsorption studies and theoretical studies carried out pointed to physisorption as the mechanism for adsorption of DBT in both CPs with interactions being predominantly dispersion forces between the ligands and DBT. [ABSTRACT FROM AUTHOR]

A dinuclear zinc complex [Zn2L2] (1), and four mononuclear zinc complexes [ZnBr2(LH)2] (2), [ZnCl2(LH)2] (3), [Zn(LH)2(NCS)2] (4) and [ZnI(CH3OH)L] (5), have been prepared from the Schiff base 5-bromo-2-((cyclohexylimino) methyl)phenol (HL) by microwave irradiation method. All the zinc complexes were characterized by CHN elemental analyses, infrared and electronic spectra. Structures of the complexes were further studied by single crystal X-ray determination, which reveals that all the zinc atoms in the complexes are in tetrahedral geometry. The halide and pseudohalide anions are preferred co-ligands in the preparation of such complexes with binary ligands. The biological activity of the complexes on the bacterial strains Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli was evaluated. The complexes bearing halide and pseudohalide ligands show effective activities on the bacteria strains. [ABSTRACT FROM AUTHOR]

By utilizing the well-known selective xanthine oxidase inhibitor topiroxostat, a new zinc(II) complex Zn(L)2(H2O)2 (1) [HL = 4-(3-(pyridine-4-yl)-1H-1,2,4-triazol-5-yl)picolinic acid] has been hydrothermally synthesized, involving in-situ ligand formation upon hydrolysis of topiroxostat. The complex has been structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. X-ray structural analysis revealed that complex 1 is a N,O-chelating mononuclear Zn(II) complex. Complex 1 shows good thermal stability and exhibits photoluminescence in the solid state at room temperature. Moreover, complex 1 has been shown to be effective in the solvent-free ring-opening polymerization of ε-caprolactone without any co-catalyst or initiator. [ABSTRACT FROM AUTHOR]

New benzohydrazone compound, 4-amino-N'-[(1E)-1-(2-hydroxy-6-methyl-4-oxo-4H-pyran-3-yl)ethylidene] benzohydrazide (HL1) and its Cu(II), Ni(II), Zn(II) and Mn(II) complexes were synthesized. The structures of HL1 and its complexes were elucidated by elemental analysis and IR, UV-Vis, 1H and 13C NMR spectroscopy and mass spectrometry. The infrared spectral data of the complexes revealed that HL1 coordinated with the metal ions through azomethine nitrogen, enolic oxygen and amide carbonyl oxygen atoms, hence, HL1 behaves as a monobasic tridentate ligand. UV-Vis data revealed that Zn(II) and Mn(II) complexes adopted octahedral geometry, while Cu(II) and Ni(II) complexes had five-coordinate and square-planar geometries respectively. The mass spectra data and elemental analysis values are in accordance with the calculated values for the suggested molecular formula of the complexes, a confirmation of the 1:1 ligand to metal stoichiometry in case of Cu(II) complex and 2:1 ligands to metal stoichiometry in case of the other complexes. [ABSTRACT FROM AUTHOR]

A new rigid bipyridinyl-derived ligand has been utilized for the fabrication of two metal–organic frameworks, denoted as [M(L)(mipa)]n [M = Zn (1) and Cd (2), L = 2,6-bis((E)-4-(pyridine-3-yl)benzylidene)cyclohexanone, H2mipa = 5-methylisophthelic acid], through solvothermal synthesis by using a mixed-ligand strategy. Structural analysis reveals that these isomorphic compounds display a 3,5-connected two-dimensional network with an unprecedented (42·67·8)(42·6) topology. Both of them exhibit certain chemical stability and thermal stability. Notably, the photocatalytic properties of the two compounds for the degradation of several organic dyes have been explored. [ABSTRACT FROM AUTHOR]

The synthesis, structure and photophysical properties of two polynuclear zinc complexes, namely [Zn6L2(µ3-OH)2(OAc)8] (1) and [Zn4L4(µ2-OH)2](ClO4)2 (2), supported by tridentate Schiff base ligand 2,6-bis((N-benzyl)iminomethyl)-4-tert-butylphenol (HL) are presented. The synthesized compounds were investigated using ESI-MS, IR, NMR, UV-vis absorption spectroscopy, photoluminescence spectroscopy and single-crystal X-ray crystallography. The hexanuclear neutral complex 1 comprises six-, five- and four-coordinated Zn2+ ions coordinated by O and N atoms from the supporting ligand and OH- and acetate ligands. The Zn2+ ions in complex cation [Zn4L4(µ2-OH)2]2+ of 2 are all five-coordinated. The complexation of ligand HL by Zn2+ ions leads to a six-fold increase in the intensity and a large blue shift of the ligand-based 1(π-π)* emission. Other biologically relevant ions, i.e., Na+, K+, Mg2+, Ca2+, Mn2+, Fe2+, Co2+, Ni2+ and Cu2+, did not give rise to a fluorescence enhancement. [ABSTRACT FROM AUTHOR]

Bidentate Schiff bases (I1–I9) are synthesized by condensation between substituted anilines, benzothiazoles, and 2-hydroxy aromatic aldehydes. The Zn(II) derivatives (1–9) are prepared by reacting the respective ligand and zinc acetate dihydrate in a 2:1 mole ratio in dry methanol using triethylamine as a base. They are characterized by FTIR, NMR, and single-crystal XRD techniques. The XRD data confirmed distorted tetrahedral molecular geometry for 6; the intermolecular interactions are investigated comprehensively by 3-D Hirschfeld surface analysis and 2-D fingerprint plots. The DFT studies for the compounds are conducted for geometrical and energy optimization by applying 3-21 G* and 6-311++G (d, p)/B3LYP basis sets. Molecular docking data show that ligands possess GOLD scores in the range 51.5–46.7, whereas 2 and 3 have shown good fitness score of 57.7 and 53.3, respectively, with a maximum score of 60.2 for 7. The antibacterial data for 7 shows zone of inhibition as 17.3 mm against Staphylococcus aureus and 16.3 mm against Staphylococcus epidermidis, whereas 2 exhibits maximum value of 15.6 mm against gram negative bacteria Escherichia coli. The maximum and comparable alpha amylase inhibition potential of 12.6 and 12.3% are found for 8 and 3, respectively. [ABSTRACT FROM AUTHOR]

The N2O2-tetradentate Schiff-base complex of zinc(II) was synthesized by the template reaction of 5-ethoxy-2-hydroxy-acetophenone-S-methylthiosemicarbazone and 2-hydroxy-benzaldehyde (1)/2-hydroxy-4-methoxy-benzaldehyde (2). The compounds were characterized by elemental analysis, UV–visible, FT-IR, 1H NMR spectra, and thermogravimetric analyses. Antioxidant activities of the compounds were determined with Cupric Reducing Antioxidant Capacity and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. The molecular geometries and vibrational frequencies were calculated using density functional theory (DFT/B3LYP) with the 6-311++G(d,p) basis set. The 1H NMR chemical shift values of the ligand and complexes in the ground state were calculated with the gauge-independent atomic orbital (GIAO) approach applying the same method and the basis set and compared with the experimental data. Using the TD-DFT method, electronic absorption spectra of the complexes were predicted at the same level. Also, the non-covalent interaction (NCI) plot index analysis reveals the presence of different kinds of non-covalent interactions in all complexes. [ABSTRACT FROM AUTHOR]

Synthesis of three metal complexes, Co(II), Ni(II), and Zn(II) by using novel Schiff base as 6,6'((1E,l'E)- ((1,3phenylenebis(methylene))bis(azanylylidene))bis(methanylylidene))bis(2,4dibromophenol). All these complexes were characterized using 1H NMR, FTIR, XRD, and TGA. The Complexes synthesized metal ion: ligand ratio 1:1. The Schiff base ligand and their metal complexes were screened for antibacterial, and antifungal activity tested, and compared with the standard. The anticancer activity of Schiff base and their metal complexes tested against MCF -7 human breast cell line shows moderate to good activity. The antioxidant activity of Schiff bases and metal complex tested shows moderate activity. [ABSTRACT FROM AUTHOR]

By condensation from substituted carbonyl compounds and anthranilamide under toluene reflux conditions, a wide range of 2,3-dihydroquinazolin-4(1H)-ones were produced in fair to good yields with the use of a Lewis acid catalyst Zn(OAc)2•2H2O (10 mol%), which is inexpensive, accessible, and environmentally friendly. All the synthesized compounds were properly described using melting point, IR, NMR, and mass spectral studies, and the findings were compared with information from the earlier literature. The new method has a number of advantages over the traditional methods for the synthesis of divergent 2,3-dihydroquinazolin-4(1H)-ones, including a higher product conversion, a wide substrate range, and the absence of undesirable side products. Aliphatic, heteroaromatic and aromatic carbonyl compounds were well tolerated under the optimized reaction conditions. [ABSTRACT FROM AUTHOR]

The syntheses and crystal structures of four hydrothermally prepared organo-zinc phosphites, viz. poly[[(2-amino-3-methylpyridine)-μ3-phosphonato-zinc] hemihydrate], {[Zn(HPO3)(C6H8N2)]·0.5H2O}n, (I), poly[(2-amino-4-methylpyridine)- μ3-phosphonato-zinc], [Zn(HPO3)(C6H8N2)]n, (II), poly[(2-amino-5- methylpyridine)-μ3-phosphonato-zinc], [Zn(HPO3)(C6H8N2)]n, (III), and poly[bis(2-amino-4-methylpyridinium) [tetra-μ3-phosphonato-trizinc] monohydrate], {(C6H9N2)2[Zn3(HPO3)4]·H2O}n, (IV), are described. Compounds (I)- (III) are constructed from vertex-sharing ZnO3N tetrahedra (the organic molecule acting as a ligand) and HPO3 pseudo pyramids in a 1:1 ratio to generate the same motif of infinite 4-ring 'ladder' chains propagating in the [010], [101] and [100] directions, respectively, whereas (IV) consists of (010) layers of vertex-sharing ZnO4 and HPO3 units in a 3:4 ratio with the protonated organic molecule acting as a template. When an excess of HCl is used in the synthesis, the simple hydrated molecular salt, bis(2-amino-3-methylpyridinium) tetrachlorozincate monohydrate, (C6H8N2)2[ZnCl4]·H2O, (V), arises. Compounds (I)-(V) feature extensive networks of hydrogen bonds, both classical (N--H· · ·O, N--H· · ·Cl, O--H· · ·O) and non-classical (C--H· · ·O, C--H· · ·Cl) in nature, which help to consolidate the extended structures. [ABSTRACT FROM AUTHOR]

Two new trinuclear zinc(II) complexes, [Zn3I2L2(H2O)2] (1) and [Zn3(CH3OH)(DMF)L2(NCS)2] (2), where L is the dianionic form of N,N'-bis(5-bromosalicylidene)-1,2-cyclohexanediamine (H2L), have been synthesized and characterized by elemental analyses, IR and UV spectra. Structures of the complexes were further confirmed by single crystal X-ray diffraction. Both complexes are trinuclear zinc compounds. Both compounds are solvated, with water ligand for 1 and methanol ligand for 2. The outer two Zn atoms are in square pyramidal coordination, while the inner one is in octahedral coordination. The effect of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans were evaluated, and gave interesting results. [ABSTRACT FROM AUTHOR]

This paper is intended to prepare new antimicrobial complexes with proven efficiency. The Schiff base, through the condensation process of salicylaldehyde and p-toludine, and its Cu and Zn complexes were successfully synthesized. The Schiff base and its complexes were characterized using molar conductivity, Ultraviolet-visible (UV-Vis), atomic absorption spectroscopy (AAS), and Fourier transform infrared (FTIR) techniques. Accordingly, these characterizations not only confirmed that the synthesized Schiff base acted as N,O bidentate ligand (through azomethine nitrogen and phenoxide oxygen) and chelated with Cu(II) and Zn(II) in the metal-to-ligand ratio of 1:2 but also revealed the characteristic electronic-transition of π→π*/n→π* of the ligand, and ligand-metal charge transfer and d-d of the metal complexes. Moreover, both Cu and Zn complexes recorded weak molar conductance of 54.12 and 51.41 S cm² mol-1, respectively. Further, their antibacterial activities were evaluated by disc diffusion assay against Staphylococcus aureus (gram-positive), Escherichia coli (gram-negative), and Bacillus cereus (gram-negative) bacteria. For all microbial, the metal complexes recorded higher activities than the parent ligand; such increased activity of the complexes may be due to the chelation of the metal ion in the complexes, which enhances the lipophylic character favoring its permeation through the lipid layer of the cell membrane. Such metal complexes can therefore be explored in the future as an option for decreasing the pathogenic potential of infecting bacteria. [ABSTRACT FROM AUTHOR]

The current study focuses on producing zinc oxide nanoparticles (ZnO-NPs) from aqueous leave extracts because it is more environmentally friendly and cost-effective than traditional physical and chemical methods. Synthesis of aqueous extracts of Moringa Oleifera, Ocimum tenuiflorum (Tulsi), and Neem (Azadirachta indicia) leaves. Zinc acetate dihydrate (Zn (CH3COO)2.2H2O) was used as a precursor to biosynthesize ZnO-NPs at different temperatures (50, 75, and 100 °C) for 1 hour of the synthesis of Zinc oxide nanoparticles (ZnO-NPs) were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transforms infrared (UV). The presence of biomolecules such as polyphenols, carboxylic acid, polysaccharides, and amino acids was revealed by FTIR analysis of green synthesized nanoparticles. The results of the SEM study of green synthesized ZnO nanoparticles revealed that the sample exhibits a compact arrangement of homogeneous nanoparticles with a spherical shape and successfully unfolded it was crystalline structure nature. [ABSTRACT FROM AUTHOR]

Five neutral zinc(II) complexes of 3-bromo-5-chloro-salicylaldehyde (3-Br-5-Cl-saloH) were synthesized in the absence or presence of the nitrogen-donor co-ligands 2,2′-bipyridine (bipy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (neoc), or 2,2′-bipyridylamine (bipyam) and were characterized by various techniques. The obtained complexes were [Zn(3-Br-5-Cl-salo)2(H2O)2] (1), [Zn(3-Br-5-Cl-salo)2(bipy)] (2), [Zn(3-Br-5-Cl-salo)2(phen)] (3), [Zn(3-Br-5-Cl-salo)2(neoc)] (4) and [Zn(3-Br-5-Cl-salo)2(bipyam)] (5). The crystal structures of complexes 1 and 3 were determined by single-crystal X-ray crystallography. The interaction of the compounds with calf-thymus DNA takes place via intercalation. The compounds may moderately cleave pBR322 plasmid DNA at a concentration of 500 μM. The compounds may bind tightly and reversibly to serum albumins. The antioxidant activity of the compounds was examined towards 1,1-diphenyl-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and H2O2. The antimicrobial potency of the compounds was investigated against Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Escherichia coli NCTC 29212 and Xanthomonas campestris ATCC 1395. [ABSTRACT FROM AUTHOR]

Gemifloxacin mesylate is a synthetic fluoroquinolone derived antimicrobial agent. Two metal complexes of gemifloxacin mesylate were synthesized viz. gemifloxacin-Fe and gemifloxacin-Zn. The formed complexes were characterized by using TLC, TGA and FT-IR spectra analyses. The formed complexes were then evaluated for antimicrobial activity. The newly formed two complexes were assessed against nine bacterial and one fungal strain, where gemifloxacin (30 µg/disc) was used as a reference standard. The new complexes showed better activity than the standard reference drug against Klebsiella pneumoniae among nine bacterial strains. But two bacterial species, Acinetobacter lwoffii and Enterococcus faecium, and the fungal strain Candida albicans showed complete resistance to the newly synthesized complexes and the reference standard. The drug protein interaction with the Bovine Serum Albumin (BSA) was also studied. The interaction mechanism was explored, suggesting that gemifloxacin and its Zn (II) complex interact with BSA via a static process while the Fe (II) complex interacts via a dynamic process and the lower Ksv value also indicated that drug - BSA complexes were formed in ground-state. [ABSTRACT FROM AUTHOR]

New azomethine compounds of 2-(N-tosylamino)benzaldehyde or 5-chloro-2-(N-tosylamino)benzaldehyde and the corresponding chlorine-substituted anilines, zinc(II) complexes based on them have been synthesized. The structures of azomethines and their complexes were determined by elemental analysis, IR, 1H NMR, X-ray spectroscopy, and X-ray diffraction. It is found that all ZnL2 complexes have a tetrahedral structure according to XAFS and X-ray diffraction data. The photoluminescent properties of azomethines and zinc complexes in methylene chloride solution and in solid form have been studied. It is shown that the photoluminescence quantum yields of solid samples of the complexes are an order of magnitude higher compared to the solutions and range from 11.34% to 48.3%. The thermal properties of Zn(II) complexes were determined by thermal gravimetric analysis (TGA) and differential scanning calorimetry. The TGA curves of all the compounds suggest their high thermal stability up to temperatures higher than 290 °C. The electrochemical properties of all complexes were investigated by the cyclic voltammetry method. The multilayered devices ITO/PEDOT:PSS/NPD/Zn complex/ TPBI/LiF/Al with wide electroluminescence (EL) color range spanning the range from bluish-green (494 nm) to green (533 nm) and the high values of brightness, current and power efficiency were fabricated. The biological activity of azomethines and zinc complexes has been studied. In the case of complexes, the protistocidal activity of the zinc complex with azomethine of 5-chloro-2-(N-tosylamino)benzaldehyde with 4-chloroaniline was two times higher than the activity of the reference drug toltrazuril. [ABSTRACT FROM AUTHOR]

Six new chiral zinc(ii) complexes 1–6 based on ethylenediamine derivatives of terpenes were synthesized and characterized. The molecular structure of complex 2 was established by X-ray diffraction analysis. The modulating effect of complexes 1–6 on the functional state of mitochondria, which are organelles playing an utterly important role in maintaining the energy balance of cells, transfer of genetic material, and regulation of the processes of triggering the cell death by apoptosis, autophagy, and necrosis, was studied. It is shown that synthesized zinc complexes lead to depolarization of the mitochondrial membrane, an increase in the threshold of sensitivity of the organelles to calcium-induced opening of the mitochondrial permeability transition pores, and disruption of the operation of the respiratory chain complexes in these organelles. Such a dysfunctional state of mitochondria is one of the main causes of cell death through apoptosis due to the release of various proapoptotic factors into the intracellular space. In this regard, the newly synthesized zinc complexes 1–6 can be considered as destructive agents aimed at triggering cell death cascades by affecting mitochondrial functions. These properties are of paramount importance when searching for potential drugs with possible antitumor, antiprotozoal, or antifungal activity. [ABSTRACT FROM AUTHOR]

In this paper, a novel method of synthesis of zinc cobalt selenide (ZnCoSe) nanostructures via the hydrothermal method is introduced that is comprised of two stages as opposed to the direct method that could be done in a single stage. In the single-stage method, the consequent electrodes were covered by ZnCoSe that was directly and immediately synthesized while in the two-stage method, first, zinc cobalt oxide (ZnCoO) was hydrothermally produced then the oxygen atoms were replaced by selenium and the ZnCoSe* electrode was indirectly obtained. The structural and electrochemical evaluations showed boosted performance of the ZnCoSe* whose structure was found to be nanowire. In this paper, the specific capacitance values (Csp) of the ZnCoSe*, ZnCoO and ZnCoSe electrodes were measured to be 104, 64 and 62 F.g-1 at 20 mV/s scan-rate by Cyclic voltammetry (CV) which alongside the Galvanostatic Charge-Discharge (GCD) analysis, led us to conclude superior activity of the ZnCoSe* electrode. Electrochemical impedance spectroscopy (EIS) was also performed and its results were in accordance with those of the cyclic voltammetry. Based on the EIS results, ZnCoSe* showed the smallest charge transfer resistance (6.5 ohm/cm-2) and consequently the supreme electrochemical behavior among the studied electrodes. Moreover, a better capacity retention value was recorded in the cyclability test of the ZnCoSe* electrode as the specific capacity value of this electrode reached 145% of its initial value after 2000 cycles. [ABSTRACT FROM AUTHOR]

In this work, green synthesized cobalt monometallic and cobalt–zinc bimetallic NPs were prepared by bioreduction of metallic salts with Cymbopogan citratus plant extract. Biosynthesized cobalt nanoparticles (NPs) and cobalt–zinc bimetallic NPs were characterized using diverse techniques such as FTIR, UV-Visible spectroscopy, SEM, XRD, and EDX analyses. UV-visible spectra for green-synthesized cobalt monometallic and cobalt–zinc bimetallic NPs were in the range between 300 to 350 nm, which confirmed the formation of stable monometallic and bimetallic NPs. The average particle size of CoNPs calculated by XRD analysis was found to be 22.77 nm and that of Co-Zn BMNPs was 14.8 nm. Different functional groups in the Cymbopogan citratus plant extract, which served as a reducing and stabilizing agent for NPs, were identified by FTIR spectra. Cobalt NPs and cobalt–zinc bimetallic NPs were used in the evaluation of antioxidant, anti-inflammatory, and dye degradation activity. Green-synthesized cobalt monometallic NPs and cobalt–zinc bimetallic NPs exhibited excellent antioxidant activity with the scavenging of DPPH free radicals. Green synthesized cobalt NPs and cobalt–zinc bimetallic NPs were utilized for the removal of methylene blue (MB) dye. Different parameters such as the effect of temperature, pH, and dye concentration on adsorbent doses were analyzed and optimized. The best dye removal percentage was obtained with Co-Zn BMNPs compared with CoNPs. Cobalt NPs and cobalt–zinc bimetallic NPs did not display good anti-inflammatory activity because of the presence of secondary metabolites which inhibited them to react with proteins. [ABSTRACT FROM AUTHOR]

In this work, we report on the synthesis of a novel zinc(II) coordination compound [ZnL 2 ] (1), which was readily obtained from the reaction of Zn(OAc)·2H 2 O and N′ -(pyridin-2-ylmethylene)nicotinohydrazide (HL) in methanol. Recrystallization of 1 from dimethylformamide under ambient conditions allowed to produce yellow block-like crystals of 1 ·H 2 O. Complex 1 ·H 2 O was characterized by FT-IR and 1H NMR spectroscopy, while its optical properties were studied by UV–vis and spectrofluorimetry in methanol. The crystal structure of the title complex was revealed by single crystal X-ray diffraction and further explored in detail by the Hirshfeld surface analysis. Theoretical investigations based on the DFT calculations have also been applied to show the electronic properties of complex 1. The antitumor activities of the parent ligand HL and complex 1 were studied using Dalton's lymphoma malignant cancer model. Both compounds were found to induce concentration-dependent cytotoxicity and apoptotic cell death, leading to a decrease in cell viability, body weight, and tumor volume in mice with the superior activity of complex 1 over HL. Mice treated with complex 1 demonstrated an increase in life span with a survival period of 23 days. Finally, using a molecular docking approach, we have probed complex 1 to inhibit the recombinant mouse tumor-necrosis factor alpha (mTNF). [ZnL 2 ] (1), obtained from N′ -(pyridin-2-ylmethylene)nicotinohydrazide (HL), is reported. DFT studies revealed its electronic properties. The antitumor activities of HL and 1 were also studied. Mice treated with 1 demonstrated an increase in life span. According to molecular docking results, 1 can inhibit the recombinant mouse tumor-necrosis factor alpha (mTNF). [Display omitted] • [ZnL 2 ] (1) obtained from N′ -(pyridin-2-ylmethylene)nicotinohydrazide (HL) is reported • The antitumor activities of HL and 1 were studied • HL and 1 induce cytotoxicity and apoptotic cell death with the superior activity of 1 • Mice treated with 1 demonstrated an increase in life span [ABSTRACT FROM AUTHOR]

[Display omitted] • Four new Metal-Saccharin complexes were synthesized using neutral N , N -bis(2-hydroxyethyl)-ethylenediamine ligand. • Interestingly, the two neutral ligands coordinated to the Co(III) ion as an anionic tridentate ligand. • Frontier Molecular Orbital (FMO) energies were calculated to predict the chemical reactivity of the complexes. • Theoretical and experimental data regarding the new crystal structures were found to be highly compatible with each other. New Co(III), Ni(II), Cu(II), and Zn(II) saccharinate (Sac) complexes bearing with N , N -bis(2-hydroxyethyl)ethylenediamine (N-bishydeten), namely [Co(2H N-bishydeten) 2 ](Sac)⋅2H 2 O, [Ni(Sac) 2 (N-bishydeten)], [Cu(N-bishydeten) 2 ](Sac) 2 and [Zn(Sac) 2 (N -bishydeten)] were synthesized and characterized using UV–Vis, IR spectroscopy and magnetic susceptibility measurements. The crystal structures of the complexes were analysed by single crystal X-ray diffraction. Both N-bishydeten and Sac displayed coordination versality. The N-bishydeten ligands were octahedrally coordinated as two tridentate anionic ligands (2H N-bishydeten) (N, N, O-) to the Co(III) and two tridentate neutral ligands (N, N, O) to the Cu(II). The anionic Sac ligand was also located outside the coordination sphere in these complexes. However, the N-bishydeten ligand behaved as a tetradentate ligand (O, N, O, N) in the Ni(II) and Zn(II) complexes while two Sac ligands were coordinated the corresponding metals ions in a monodentate fashion, one through the N atom and the other via the carbonyl O atom. Thermal decomposition of the complexes was studied in inert atmosphere and thermal analysis data (TG and DTA) indicated multi-step decompositions of the metal complexes decomposed in a single stage. The thermal decomposition products were estimated as metal oxides. Finally, the structural properties of all complexes were investigated through quantum chemical computations. [ABSTRACT FROM AUTHOR]

Two new nickel(II) complexes and two new zinc(II) complexes derived from N,N' -bis(4-bromo-2-hydroxybenzylidene)-2-hydroxy-1,3-propanediamine were synthesized and characterized. Structures of the Schiff base and the complexes were determined by single crystal X-ray diffraction. [Display omitted] A new Schiff base compound N,N' -bis(4-bromo-2-hydroxybenzylidene)-2-hydroxy-1,3-propanediamine (H 2 L) has been prepared. With the Schiff base as ligands, two new nickel(II) compounds [NiL] (1) and [Ni 3 L 2 (CH 3 COO) 2 (CH 3 OH) 2 ] (2), and two new zinc(II) compounds [ZnL(OH 2)] (3) and [Zn 3 L 2 (CH 3 COO) 2 ]·CH 3 OH·2dmf (4), were synthesized. The Schiff base and the four coordination compounds have been characterized by means of elemental analysis, IR and UV–Vis spectra, as well as 1H and 13C NMR spectra (for H 2 L). Structures of H 2 L and the coordination compounds were further determined by single crystal X-ray diffraction. The Ni atom in compound 1 is in square planar coordination, and those in compound 2 are in octahedral coordination. The Zn atom in compound 3 is in square pyramidal coordination. The outer and inner Zn atoms in compound 4 are in square pyramidal and octahedral coordination, respectively. The self-assembly of the coordination compounds is discussed. [ABSTRACT FROM AUTHOR]

The trinuclear zinc calix[4]arene complexes [Zn3(O2CCH3)2(L(O)2(OMe)2)2·xMeCN (x = 7.5, 1; x = 6, 1′), [Zn3(O2CCH3)2(L(O)2(OnPr)2)2·5MeCN (2·5MeCN), [Zn3(OEt)2(L(O)2(OMe)2)2]·4MeCN (3·4MeCN), [Zn3(OEt)2(L(Opentyl)2)2]·4.5MeCN (4·4.5MeCN) and [Zn3(OH)2(L(O)2(On-pentyl)2]·8MeCN (5·8MeCN) have been isolated from reaction of [(ZnEt)2(L(O)2(OR)2)2] (L(OH)2(OR)2 = 1,3-dialkoxy-4-tert-butylcalix[4]arene; R = methyl, n-propyl or pentyl) and the reagents acetic acid, ethanol, and presumed adventitious water, respectively. Attempts to make 5via a controlled hydrolysis led only to the isolation of polymorphs of (L(OH)2(Opentyl)2·MeCN. Reaction of [Zn(C6F5)2] with L(OH)2(Opentyl)2, in the presence of K2CO3, led to the isolation of the complex [Zn6(L(On-pentyl))2(OH)3(C6F5)3(NCMe)3]·3MeCN (6·3MeCN). The molecular structures of 1–6 reveal they all contain a near linear (163 to 179°) Zn3 motif. In 1–5, a central tetrahedral Zn centre is flanked by trigonal bipyramidal Zn centres, whilst in 6, for the linear Zn3 unit, a central distorted octahedral zinc centre is flanked by trigonal planar and a tetrahedral zinc centres. Screening for the ring opening polymerization (ROP) of ε-caprolactone at 90 °C revealed that they are active with moderate to good conversion affording low to medium molecular weight products with at least two series of ions. For comparative studies, the trinuclear aminebis(phenolate) complex [Zn3(Oi-Pr)2L/] (L/ = n-propylamine-N,N-bis(2-methylene-4,6-di-tert-butylphenolate) I was prepared. Kinetics revealed the rate order I > 4 > 6 ≈ 2 ≈ 1 > 3. [ABSTRACT FROM AUTHOR]

The conversion of propane into aromatic hydrocarbons over zinc-containing MFI zeolites with a micro-mesoporous structure was studied. The effect of a grade of carbon black used as the second structure-forming component in the synthesis of zinc aluminosilicates on their physicochemical properties, catalytic activity, and stability in the course of propane aromatization was investigated. The acid characteristics of the catalysts were studied using the thermal desorption of ammonia. The morphology and sizes of the crystals of synthesized zinc aluminosilicates were determined by scanning electron microscopy. The nature and concentration of coke deposits formed on the surface of zinc aluminosilicates in the reaction of propane aromatization were determined by differential thermal analysis. It was found that the addition of carbon black to the crystallization gel in the course of synthesis resulted in the production of zinc aluminosilicates having a higher operational stability compared to that of microporous Zn-containing zeolite. [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]

Keywords: coordination polymer; crystal structure; zinc complex EN coordination polymer crystal structure zinc complex 561 564 4 07/18/22 20220701 NES 220701 1 Introduction The continuous search and synthesis of novel coordination polymers (CPs) with unique structures and properties are dominantly driven by their fascinating structural and compositional diversities and manifold potential applications in catalysis [[1]], [[2]], [[3]], magnetism [[4]], [[5]], [[6]], [[7]], [[8]], [[9]], sensors [[10]], [[11]], [[12]], [[13]], adsorption/separation [[14]], and material science [[15]], [[16]], [[17]], [[18]], [[19]], [[20]]. 20 Yang, X.-G., Zhai, Z.-M., Lu, X.-M., Zhao, Y., Chang, X.-H., Ma, L.-F. Dalton Trans. 2019, 48, 10785-10789; https://doi.org/10.1039/c9dt02178g. 22 Chang, X.-H., Ling, X.-L., Lu, X.-M., Yang, X.-G., Li, F.-F., Guo, Y.-M. [Extracted from the article]

C30H22F2N2O4Zn, monoclinic, P2/c (no. 13), a = 9.5936(8) Å, b = 11.2561(10) Å, c = 11.9682(10) Å, β = 104.598(3)°, V = 1250.68(19) Å3, Z = 2, Rgt(F) = 0.0661, wRref(F2) = 0.1259, T = 173(2) K. [ABSTRACT FROM AUTHOR]