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Ruthenium(III) complexes of the type [RuX2(PPh3)(L)] (where X = Cl/Br; L = Benzothiazolyl-Salal Schiff base ligand) has been synthesized. The synthesized complexes were characterized by various physicochemical and spectral techniques. An octahedral geometry has been tentatively proposed for all the complexes. The cytotoxic activity of the synthesized ruthenium(III) complexes has shown significant activity against a panel of microbes. [ABSTRACT FROM AUTHOR]

The reactions of benzothiazolyl thiosemicarbazone with [RuX3(PPh3)3] (X = Cl/Br) in a 1:1 molar ratio have given stable solid complexes corresponding to the general formula [RuX(PPh3)2(L)]. Structural features were determined by analytical and spectral techniques. DNA binding properties of the ligands and its ruthenium(III) complexes have been investigated by electronic absorption spectroscopy. The complexes show good binding affinity to calf-thymus DNA. Gel electrophories of pBR322 DNA with complexes demonstrated that the complexes exhibit excellent cleavage activityviaoxidative pathway. In addition, the antioxidant activity of the free ligands and its complexes was determined by DPPH and hydroxyl radicals. The complexes were found to possess potent antioxidant activity. [ABSTRACT FROM PUBLISHER]

Highlights: [•] New cis and trans Ru(III) complexes with NSNO donor azo thioether ligand. [•] Pseudo octahedral geometry of cis complex has been confirmed by X-ray structure. [•] DFT calculation has been used to predict the electronic structure of the complexes. [•] The electronic spectra have been interpreted by TDDFT calculation. [•] Ru(III) complexes catalyze oxidation of alcohols to carbonyl compounds with NMO. [ABSTRACT FROM AUTHOR]

Binuclear ruthenium(III) complexes [RuX3L]2 · nH2O (X = Cl, L = L1, L2, L3; n = 1, L4 and L5, X = Br; L = L3), [RuX3L1.5]2 · nH2O (X = Br, L = L1; n = 0, L4; n = 6 and L5; n = 10), and [RuX3L2]2 (X = Br, L = L2) have been isolated by treatment of hydrated RuX3 (X = Cl/Br) in acetone with 2-(2′-aminophenylbenzimidazole) (L1), 2-(3′-aminophenylbenzimidazole) (L2), 2-[(3′-N-salicylidinephenyl)benzimidazole] (L3), 2-(3′-pyridylbenzimidazole) (L4), and 2-(4′-pyridylbenzimidazole) (L5) in acetone. The complexes were characterized by elemental analysis, conductivity and magnetic susceptibility measurements, IR, electronic, EPR, and mass spectral studies. The complexes were dimeric; based on analytical and spectral studies, an octahedral geometry was proposed for the complexes. The synthesized complexes were screened against Gram-positive and Gram-negative bacteria and fungi. [ABSTRACT FROM PUBLISHER]

New copper and ruthenium mononuclear complexes of the type [ML2(H2O)X] [X = H2O for M = Cu(II) and X = Cl for M = Ru(III)] have been prepared from 1-p-diphenyl- methane-2-hydroxyimino-2-(4-chloroanilino)-1-ethanone (HL1) and 1-p-diphenylmethane-2-hydroxyimino-2-(4-toluidino)-1-etha- none (HL2). The complexes were characterized by elemental analyses, magnetic susceptibility, molar conductance, IR, thermal analysis, and cyclic voltammetry. Stoichiometric and spectral results of the metal complexes indicated that the metal:ligand ratios in the complexes were found to be 1:2 and the ligands behave as a bidentate ligand forming neutral metal chelates through the carbonyl and oxime oxygen. The electrochemical behavior of the ligands and their complexes were obtained by cyclic voltammetry. The interaction between these complexes with DNA has also been investigated by agarose gel electrophoresis. The copper(II) complexes (3 and 4) with H2O2 as a co-oxidant exhibited strongest cleaving activity. Moreover, catalytic activities of the complexes for the disproportionation of hydrogen peroxide were also investigated in the presence of imidazole. [ABSTRACT FROM PUBLISHER]

Abstract: The ruthenium(III) complexes [Ru(L n )2]ClO4 with 4-R-2-((2-(pyridin-2-yl)hydrazono)methyl)phenol (HL n ; R =H, Cl, Br, Me and OMe) have been synthesized. Microanalysis, magnetic susceptibility and various spectroscopic (IR, UV–Vis and EPR) measurements have been used for the characterization of these complexes. The molecular structures of all the complexes, except for the complex where R =Br, have been confirmed by a single crystal X-ray diffraction study. The metal centers in these complex cations are in a distorted octahedral N4O2 environment formed by the pyridine-N, the imine-N and the phenolate-O donor (L n )− ligands. Intermolecular hydrogen-bonding assisted supramolecular structures assembled by the solvated complexes range from dimeric to one-dimensional chain to two-dimensional sheet structures. [Copyright &y& Elsevier]

Abstract: New hexa-coordinated Ru(III) complexes of the type [Ru(H2Pzdc)(EPh3)3X2] have been synthesized by reacting 3,5-pyrazole dicarboxylic acid (H3Pzdc) with the appropriate starting complexes [RuX3(EPh3)3] (where X=Cl or Br; E=P or As). The ligand behaves as a bidentate monobasic chelate. All the complexes have been characterized by analytical and spectroscopic (IR, electronic and EPR) data. Single-crystal X-ray analysis of the complex [Ru(H2Pzdc)(PPh3)2Cl2]·C6H6·C2H5OH revealed that the coordination environment around the ruthenium center consists of an NOP2Cl2 octahedron. The planar ligand occupies the equatorial position along with two chlorine atoms, while the triphenylphosphine groups occupy the axial positions. The electrochemical behavior of the new complexes was studied using cyclic voltammetry. The new mononuclear ruthenium complexes are capable of acting as catalysts for the oxidation of alcohols. [Copyright &y& Elsevier]

Abstract: Mononuclear ruthenium(III) complexes of the type [RuX(EPh3)2(L)] (E=P or As; X=Cl or Br; L=dibasic terdentate dehydroacetic acid thiosemicarbazones) have been synthesized from the reaction of thiosemicarbazone ligands with ruthenium(III) precursors, [RuX3(EPh3)3] (where E=P, X=Cl; E=As, X=Cl or Br) and [RuBr3(PPh3)2(CH3OH)] in benzene. The compositions of the complexes have been established by elemental analysis, magnetic susceptibility measurement, FT-IR, UV–vis and EPR spectral data. These complexes are paramagnetic and show intense d–d and charge transfer transitions in dichloromethane. The complexes show rhombic EPR spectra at LNT which are typical of low-spin distorted octahedral ruthenium(III) species. All the complexes are redox active and display an irreversible metal centered redox processes. Complex [RuCl(PPh3)2(DHA–PTSC)] (5) was used as catalyst for transfer hydrogenation of ketones in the presence of isopropanol/KOH and was found to be the active species. [Copyright &y& Elsevier]