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A trinuclear copper complex [Cu3(napxshz)2(phen)2] has been synthesised using a tribasic naproxen‐appended ligand [H3napxshz = 2‐hydroxy‐N′‐(2‐[6‐methoxynaphthalen‐2‐yl] propanoyl) benzohydrazide] and 1,10‐phenanthroline. The complex was characterised by different spectroscopic methods such as Fouriertransform infrared (FT‐IR), ultraviolet‐visible (UV–Vis) and electrospray ionisation (ESI)‐mass spectroscopy. The solid‐state structure of the ligand and complex 1 was established by single‐crystal X‐ray diffraction analysis. The interaction of the complex and the ligand with DNA was investigated by UV–visible spectroscopy and fluorometric titrations. The calculated binding constants (Kb) of the complex and the ligand with ct‐DNA show that the complex has a higher binding affinity than the ligand H3napxshz. Quantum chemical calculations were performed to understand the structural aspects of the complex and its interactions with DNA. The molecular docking study reveals the interaction between DNA, and the complex is in intercalative mode. [ABSTRACT FROM AUTHOR]

Abstract: A three-dimensional supramolecule of [Cu(3,2,3-tet)] n {[Ag2(CN)4]} n (1), (3,2,3-tet = N,N′-bis(3-aminopropyl)ethylenediamine), in which [Cu(3,2,3-tet)]2+ cations are suspended in the two-dimensional anionic networks composed of [Ag2(CN)4]2+ building blocks, was synthesized and characterized by X-ray crystallography. Every silver(I) ion is five-coordinated including the silver–silver interaction in anionic network. Variable temperature magnetic susceptibility data indicate weak antiferromagnetic interaction (−0.378cm−1) between copper(II) ions in 1. [Copyright &y& Elsevier]

Abstract: An unusual copper(II) complex [Cu(L1a)2Cl2] CH3OH·H2O·H3O+Cl− (1a) was isolated from a solution of a novel tricopper(II) complex [Cu3(HL1)Cl2]Cl3·2H2O (1) in methanol, where L1a is 3-(2-pyridyl)triazolo[1,5-a]-pyridine, and characterized with single crystal X-ray diffraction study. The tricopper(II) complex of potential ligand 1,5-bis(di-2-pyridyl ketone) carbohydrazone (H2L1) was synthesized and physico-chemically characterized, while the formation of the complex 1a was followed by time-dependant monitoring of the UV–visible spectra, which reveals degradation of ligand backbone as intensity loss of bands corresponding to O→Cu(II) charge transfer. [Copyright &y& Elsevier]

Three novel trinuclear Ni(II) complexes, [Ni 3 (L 1 ) 2 (py) 4 ] ( 1 ), [Ni 3 (L 2 ) 2 (H 2 O) 2 (DMA) 2 ] ( 2 ) and [Ni 3 (L 3 ) 2 (py) 4 ] ( 3 ), with trianionic pentadentate ligands derived from salicylhydrazide with N-acyl substituents [H 3 L 1 = N 2 -crotonoylsalicylhydrazide, H 3 L 2 = N 2 -(3,3-dimethylacryloyl)salicylhydrazide, H 3 L 3 = N 2 -cinnamoylsalicylhydrazide] were synthesized and characterized by elemental analysis, spectroscopic techniques, like UV–Vis, FT-IR and NMR, molar conductivity and magnetic susceptibility measurements, and single crystal X-ray diffraction. The solid state structures of the complexes reveal the binding modes of the different ligands via ONO donor atoms. Complex 1 crystallises in the triclinic system while complexes 2 and 3 crystallise in the monoclinic system with space groups P 1 ¯ ( 1 ) and P 2 1 / c ( 2 and 3 ). Computational studies were performed using Density Functional Theory (DFT) to obtain physical properties of all three complexes. The ligands and their metal complexes were screened for antibacterial activity to assess their inhibition potential against two Gram positive bacteria; Staphylococcus aureus and Bacillus subtilis and two Gram negative bacteria; Escherichia coli and Pseudomonas aeruginosa by the well diffusion method using gentamicin as a positive control. Antibacterial screening data reveals that the trinuclear Ni(II) complexes have significantly enhanced inhibitory activities compared to the ligands. [ABSTRACT FROM AUTHOR]

The complex compound of zinc(II) supported by (Z)-2-hydroxy-N′-(1-oxoacenaphthylen-2(1H) ylidene)benzohydrazide ligand (H 2 L 1 ) has been reported and discussed. The reaction of zinc acetate with H 2 L 1 ligand leads to the formation of a mononuclear zinc(ii) complex, [Zn(HL 1 ) 2 H 2 O]. The ligand, H 2 L 1 has been characterized by elemental analysis, 1 H, 13 C and 1 H COSY -NMR, IR and ESI-MS, while the complex was characterized by elemental analysis, IR, and ESI-MS. The crystal structures of the free ligand H 2 L 1 and the complex have also been determined by single crystal X-ray diffraction. The ligand chelates with metal centre with a nitrogen atom of imino moiety and an oxygen atom of enolic group. The complex shows distorted trigonal bipyramidal geometry around the metal centre with oxygen atoms lying in the equatorial plane and imino nitrogen atoms along the axial direction. The DFT/TD-DFT calculations were performed on both the ligand and its zinc complex to get insight into the structural, electronic and optical properties. The photoluminescence, fluorescence properties of the complex have been investigated. [ABSTRACT FROM AUTHOR]

A dinuclear doubly bridged copper(II) complex [Cu 2 L 2 ] where L represents N, N′-bis(3-ethoxysalicylidene)-4-methyl-1,3-phenylenediamine has been synthesised. The ligand was characterised by elemental analysis and spectroscopic techniques such as 1H NMR, 13C NMR, FT–IR, UV–visible and ESI–mass. The copper(II) complex was characterised using partial elemental analysis, FT-IR and UV–visible spectral techniques. The solid state structure of the complex was carried out using single crystal X-ray diffraction. The crystallographic study reveals that the two copper(II) metal ions are four coordinated (O 2 N 2) via phenolate O and azomethine N atoms, forming an unusual geometry between tetrahedral and square-planar. Cyclic voltammetry of complex reveals two consecutive quasi-reversible one electron redox couples corresponding to CuII–CuII/CuII–CuI and CuII–CuI/CuI–CuI. Density Functional Theory (DFT) and Time-dependent density functional theory (TD–DFT) calculations were carried out for the determination of the optimized structures. The theoretically obtained fundamental vibrational frequencies show good agreement with observed values. The ligand binds to Cu(II) in 1:1 stoichiometry as determined by Job's plot and the binding constant is calculated as 6.8 × 102 M−1 in solution phase. The photoluminescence property of the complex has also been investigated to understand its emission behaviour. Image 1 • A tetradentate m -phenylenediamine based ligand yields a dinuclear copper complex. • The strain involved during coordination introduces a distorted tetrahedral geometry. • UV-visible spectral titrations indicate a 1:1 binding ratio for Cu2+ and H 2 L. • · DFT/TD-DFT calculations demonstrate the stability of the binuclear copper complex. [ABSTRACT FROM AUTHOR]