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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]

Hexanuclear, octanuclear, and decanuclear manganese metalladiazamacrocycles have been prepared by reacting a series of pentadentate ligands, N-acylsalicylhydrazides (N-(3-methylbutanoyl)salicylhydrazide (H33-mbshz), N-(phenylacetyl)salicylhydrazide (H3pashz), N-(3,3-dimethylbutanoyl)salicylhydrazide (H33-dmbshz), N-(2-methylpropanoyl)salicylhydrazide (H32-mpshz), N-((R,S)-2-methylbutanoyl)salicylhydrazide (H3RS-2-mbshz), N-((S)-2-methylbutanoyl)salicylhydrazide (H3S-2-mbshz), and N-(2,2-dimethylpropanoyl)salicylhydrazide (H32-dmpshz)), with manganese(II) acetate tetrahydrate. The self-assembled, supramolecular complexes assume a nearly planar cyclic structure with an -(Mn-N-N)n backbone and measure ∼2.1, ∼2.3, and ∼2.6 nm in outer diameters for n = 6, 8, and 10, respectively. The chiralities of the manganese centers on the metalladiazamacrocycle occur in alternating ⋯ΛΔΛΔ⋯ configurations. While β-branched N-acylsalicylhydrazides (H33-mbshz, H3pashz, H33-dmbshz) with a sterically flexible Cα methylene group yield 18-membered hexanuclear manganese metalladiazamacrocycles of S6 point group symmetry, α-branched N-acylsalicylhydrazides lead to 24-membered octanuclear manganese metalladiazamacrocycles or 30-membered decanuclear manganese metalladiazamacrocycles depending on the size of the N-acyl substituents. The α-branched H32-mpshz ligand with the sterically least demanding isopropyl tail at the N-acyl position yields a 24-membered octanuclear manganese metalladiazamacrocycle of S8 point group symmetry, but other α-branched N-acylsalicylhydrazides such as H3RS-2-mbshz, H3S-2-mbshz, and H32-dmpshz lead to 30-membered decanuclear manganese metalladiazamacrocycles of S10 point group symmetry. The magnetic properties of the metalladiazamacrocycles are characterized by a weak antiferromagnetic exchange interaction, with Jeff = -8.5 to -3.8 K between the Mn3+ ion spins with S = 2 in the cyclic system. [ABSTRACT FROM AUTHOR]

Discusses the coordination chemistry of thiosemicarbazones, due to their interesting physicochemical and biological properties. Means in which the thiosemicarbazones act as chelating ligands with copper (II) ion; Arrangement of two inversion-symmetry-related monomers; Coordination of the azomethine nitrogen atom to the central copper (II) ion.

A novel S4-symmetric icosanuclear manganese metalladiazamacrocycle was synthesized using a pentadentate ligand, N-3-phenyl- trans-2-propenoylsalicylhydrazide (H3L), that has a rigid and bulky terminal N-acyl group. A 20 cyclic repeat of an -(Mn-N-N)- linkage resulted in a highly puckered diaza-bridged 60-membered icosanuclear metallamacrocycle. The steric interaction between the ligands in the cyclic system leads to five consecutive MnIII centers in a chemically different -(MnAMnBMnCMnDMnE)- environment, with the chiralities of the metal centers being in a rather complicated -(ΛΛΔΛΛ)(ΔΔΛΔΔ)- sequence. [ABSTRACT FROM AUTHOR]

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]

Discrete metal-organic polyhedra (MOP) with nanosized cavities and/or clusters of MOP could be prepared when C3-symmetric facial ligands and a potential hexatopic Cu(II) ion are combined in the presence of perchlorate as a weak linker, while similar reaction conditions in the presence of a nitrate linker led to extended metal-organic frameworks made of MOP as supramolecular building blocks. [ABSTRACT FROM AUTHOR]

The article examines the utilization of the C3-symmetric facial ligands and C4-symmetric metal ions for the preparation of truncated octahedral nanocages. The curvature needed for truncation at the octahedral vertices was accomplished using ligands with a tilted pyridyl group and a nitrogen donor atom. The nanocages have 12 ports at the edges of the truncated octahedron.