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Platinum(II) complexes, [Pt(Lx)X2] (1-6), where X = Br or I and Lx = 2,2'-bipyridine or 1,10-phenanthroline derivatives (5,5'-dimethyl-2,2'-bipyridine (5-Mebpy), 4,4'-dimethyl-2,2'-bipyridine (4-Mebpy), and 5-amino-1,10-phenanthroline (5-NH2phen)) were prepared. The complexes were characterized by the elemental analysis, mass spectrometry, infrared, and multinuclear (1H, 13C and 195Pt) 1-D and 2-D NMR spectroscopies, and by single-crystal X-ray analysis of [Pt(4-Mebpy)I2] (4). All the platinum(II) complexes (1-6) were evaluated for in vitro cytotoxicity against human cancer cell lines A2780 and A2780R, and against non-malignant MRC5 cell line. All the complexes were nontoxic up to the 50 μM concentration, although they were found to readily bind to calf-thymus DNA (CT-DNA), as determined by spectrophotometric titration (Kb ∾ 107 M-1) and ethidium bromide displacement assay. [ABSTRACT FROM AUTHOR]

The interaction of MnCl2with the non-steroidal anti-inflammatory drug sodium diclofenac in the presence of 2,2′-bipyridine and pyridine resulted in the formation of cationic and neutral mononuclear complexes [Mn(diclofenac)(2,2′-bipyridine)(H2O)2] (diclofenac) (1) and [Mn(diclofenac)2(pyridine)2(H2O)2] (2), respectively. The structure of1was characterized by X-ray crystallography. In a preliminary attempt to evaluate the biological properties and possible application, the interaction of the complexes with calf-thymus DNA and human or bovine serum albumins was monitored. Additionally, the ability of the compounds to scavenge radicals such as 1,1-diphenyl-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and hydroxyl radicals was evaluated; the complexes were more potent scavengers than free sodium diclofenac. [ABSTRACT FROM AUTHOR]

A new tetrapyridine ligand, 5,5′-(3-pyridyl)-2,2′-bipyridine (2) was prepared from 5,5′-dibromo-2,2′-bipyridine (1) via Pd(0)-mediated Suzuki coupling. The reaction was performed either directly upon the free ligand, or upon its Ru(II) complex. The structures of [Ru(1)3](PF6)2and [Ru(2)3](PF6)2were studied in solution by NMR, and in the solid state by single crystal X-ray diffraction. Solution NMR data suggests distorted structures, consistent with the observed slow reactivity of the ligands towards Ru(II) ions, and their reluctance to coordinate to Fe(II) ions. However, solid-state X-ray data indicated little distortion from ideal geometries, suggesting the effect may be more electronic than steric in nature. [ABSTRACT FROM AUTHOR]

Four new compounds prepared from the ligand 2,3-dipyridyl ketone oxime (L23) with varying Cu(II) salts were synthesised and structurally characterised, {[Cu(L23)(L23-H)](ClO4)}∞(1), {[Cu(L23)(L23-H)](BF4)¼(H2O)}∞(2), [Cu3(L23-H)2(L23′)(NO3)2OH]2(NO3)2(C3H8O)6(3) and [Cu(L23)Cl2]∞(4). The effects of differing counterions, as well as the rotational conformational versatility ofL23, were demonstrated by the differing polymeric structures that were observed. Complex1and2both existed as 1-D polymeric chains withL23acting as a pseudo-tetradentate ligand through an oxime–oximato bridge. Complex1formed a helical arrangement while2formed a chiral chain with both1and2exhibiting similar chiral packing. Complex3formed an unusual inverse–9–metallacrown–3 complex, with one of theL23ligands in a zwitterionic form. Complex4was present as a simple 1-D meso-helical chain. [ABSTRACT FROM AUTHOR]

The 4-toluenesulfonyl-L-serine ligand (1), (tsserH2), was prepared from the reaction of L-serine and 4-toluenesulfonyl chloride in sodium hydroxide solution 1 M. The complexes [Pd(4,4′-dmbipy)(tsser)] (2) and [Pd(5,5′-dmbipy)(tsser)].0.5CH3CN (3) (4,4′-dmbipy is 4,4′-dimethyl-2,2′-bipyridine and 5,5′-dmbipy is 5,5′-dimethyl-2,2′-bipyridine) were also prepared from the reaction of PdCl2and 2,2′-bipyridine derivatives with 4-toluenesulfonyl-L-serine ligand in mixture of CH3CN/CH3OH (3:1) and in presence of sodium hydroxide solution 0.5 M. These compounds were characterized by elemental analysis, IR,1H NMR, and UV–Vis spectroscopy and their structures were studied by single-crystal X-ray diffraction method. The X-ray structure determinations show that in the both complexes, the PdIIatoms are four-coordinated in a distorted square-planar configuration by two N atoms from a bidentate bipyridine ligand and one N atom and one O atom from a bidentate tsser2-ligand. [ABSTRACT FROM AUTHOR]

[Ba(5,5´-dcbipy)(μ-H2O)2(H2O)2]n(1) complex was obtained from the reaction of one equivalent of 2,2'-bipyridine-5,5'-dicarboxylic acid (5,5´-dcbipy.H2) and one equivalent of ethylene diamine (en) with one equivalent of BaCl2.2H2O in water. This complex was characterized by elemental analysis, IR, UV-Vis, and luminescence spectroscopy and its structure was studied by the single-crystal X-ray diffraction method. The thermal stability of1was studied by thermogravimetric and differential thermal analyses. [ABSTRACT FROM AUTHOR]

Self-assembly of 4,4′-bipyridine (bpy) with arene-ruthenium building blocks and 2,2′-bisbenzimidazole (H2BiBzIm) in the presence of AgOTf (OTf = OSO2CF3) afforded tetranuclear cations of the type [Ru4(η6-arene)4(bpy)2(BiBzIm)2]4+(arene = p-iPrC6H4Me1, C6Me62), while similar reactions by use of [(η6-C6Me6)Ru(μ-Cl)Cl]2and excess AgOTf led to isolation of a cationic coordination network {[Ru4(η6-C6Me6)4(bpy)2(BiBzIm)2·Ag2(OTf)4]2+}n(3), which could also be obtained by treatment of [2][OTf]4with AgOTf in methanol. Complex3is constructed byπcoordination of BiBzIm(η2-carcon) with Ag(I). The coordination geometry around the silver(I) ion is pseudo-tetrahedral (taking the C=C group as one ligand). Self-assembly of only two components: [(η6-C6Me6)Ru(μ-Cl)Cl]2reacted with the 3-pyridyl-bian (mPy-bian) linker in the presence of limited AgOTf to give a chloro-bridged metalla-rectangle [Ru4(η6-C6Me6)4(μ-Cl)4(mPy-bian)2Ag]5+(4), which enclosed a silver in the center. The coordination geometry around silver(I) in4is unusual square planar. The molecular structures of1–4were confirmed by X-ray crystallography along with other spectroscopic properties. A 1-D coordination network {[Ru4(η6-C6Me6)4(bpy)2(BiBzIm)2·Ag2(OTf)4]2+}ncontaining silver triflate interaction was synthesizedviaself-assembly of [(C6Me6)RuCl2]2, 4,4′-bipyridine, and 2,2′-bisbenzimidazole in the presence of excess AgOTf or through direct reaction of metalla-rectangle [Ru4(C6Me6)4(bpy)2(BiBzIm)2]4+and AgOTf. [ABSTRACT FROM AUTHOR]

Two 1-D CdIIcoordination polymers, {[Cd(4-abpt)(hip)(H2O)2](H2O)7/2}n(1) and {[Cd(4-Habpt)(sip)(H2O)](H2O)2}n(2) (4-abpt = 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole, H2hip = 5-hydroxyisophthalic acid, H3sip = 5-sulfoisophthalic acid), have been hydrothermally synthesized and structurally characterized. Complex1has a comb-like 1-D coordination chain, while2presents a 1-D dual-track motif. The structural modulation of the coordination polymers can be achieved by simply changing the 5-substituent of the isophthalate from a hydroxyl group to a sulfonate group. Further, supramolecular architectures with higher dimensionality are constructed via hydrogen bonding and/or aromatic π-stacking interactions. Both complexes have been characterized by IR, microanalysis, and powder X-ray diffraction techniques. In addition, the solid fluorescence properties of both complexes have also been investigated. [ABSTRACT FROM AUTHOR]

Two new macrocyclic complexes, [ML](ClO4)2·4,4′-bpy [M = Cu (1) and Ni (2), L = 1,3,6,9,11,14-hexaazatricyclo [12.2.1.16,9]octadecane, 4,4′-bpy = 4,4′-bipyridine], have been synthesized and structurally characterized by X-ray crystallography analyses. Complex 1 crystallizes in the triclinic crystalline system of space group P–1, while complex 2 crystallizes in the monoclinic crystalline system of space group P21/n. In the both complexes, M(II) [M = Cu (1) and Ni (2)] centers are located in a distorted square plane environment. The weakly interactions raised the structure unit to a 3D network. [ABSTRACT FROM PUBLISHER]

A hexapositively charged tetrahedral geometry Co(II) complex was synthesized using a new positively charged ligand prepared quaternizing 4,4ʹ-bipyridine by 1-bromobutane. It is characterized by spectrometry (1H NMR, ESI MS, Uv-Vis, ICP OES), carbon, hydrogen and nitrogen (CHN) elemental analysis, halide estimation and conductivity measurement. The complex showed significantly high molar conductivity value in water (640.83 S mol−1 cm2). Its in vitro biological activities were tested on one gram-positive (Staphylococcus aureus) and one gram-negative (Klebsiella pneumoniae) bacteria. It was found active against both bacteria with improved and better activity against the latter. [ABSTRACT FROM AUTHOR]