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The Schiff base ligand, namely (7E)-N-benzylidene-2-styrylbenzen-amine-1,2-diamine-2,4-dihydroxy-phenol (L), was synthesized by condensation of 2,4-dihydroxybenzaldehyde with o-phenylenediamine. The reaction of the ligand with Fe(III), Co(II) and Ni(II) salts in an 1:1 ratio yielded three complexes (1-3). Different analytical tools, like elemental analysis, ESI-MS, UV-Vis, FT-IR, NMR and EPR spectroscopy, then molar conductivity and magnetic susceptibility spectra, were used to elucidate the structure of the ligand and complexes. Density functional theory calculation at the B3LYP/3-211G++/LANL2DZ level of the theory has been carried out to optimize the geometry of the ligand and complexes. The tetradentate ligand has coordinated to metals through ONNO donors affording octahedral geometry. Complexes were studied for their oxygen-binding activity and free radical scavenging activities. Complexes 1 and 2, which contain Fe(IIl) and Co(II), displayed reversible oxygen binding activity. On the other hand, complex 3 fails to show oxygen binding. The order of antioxidant activity is: 3 > 1 > 2 > L. [ABSTRACT FROM AUTHOR]

Tailored reaction of Schiff base ligands with palladium(II) chloride and imidazole afford three complexes of formula [Pd(II)(L)(imdz)2]Cl, which are L = 2-((E)-(p-lylimino)methyl)-6-methoxyphenol (complex 1), 2-methoxy--6-((E)-(phenylimine)methyl)phenol (complex 2) and 2-((E)-(4-chlorophenylimino) methyl)-6-methoxyphenol (complex 3). Compounds were characterized with elemental analysis, molar conductance, electronic spectroscopy, ESI-MS, FT-IR, TGA, 1H-NMR and 13C-NMR. Molecular structure and different quantum chemical parameters were calculated using the B3LYP basis set of density functional theory with the standard 6-311+G (d, 2p) level. The catalytic potential of 1-3 was examined over Heck-Mizoroki reaction and found in order of 1 > 2 > 3. [ABSTRACT FROM AUTHOR]

Molecular mechanism suggests that the incorporation of an antioxidant organic moiety to chromium will be a sound strategy for the synthesis of safer and more effective hypoglycemic compounds. Two Schiff base ligands were derived by condensation of isonicotinyl hydrazide with salicylaldehyde/o-hydroxyacetophenone which further yield four novel chromium(III) complexes of types [Cr(L)Cl2(H2O)] and [Cr(L)2]Cl. The ligands and complexes were characterized by analytical and spectroscopic techniques. DFT study at the basic set B3LYP and TD-SCF/6-311-G level was employed to confirm the geometry of the investigated compounds. Ligands were tested for their antioxidant activity and exhibited good antioxidant activity. Assessment of insulin-like activity of the complexes was initially performed in vitro by measuring the inhibition of α-amylase. The complex with highest in vitro activity was investigated for in vivo antidiabetic activity on the model of STZ-induced diabetic rats, which demonstrated that complex 4 significantly lowers the blood glucose level in rats. Toxicity level and antioxidant activity of the complex were also tested, which exhibit good tolerance level and antioxidant activity. Histological analysis of the pancreas of animals under investigation reveals the good condition of the pancreas treated with the complex. Ligands and complexes were also tested for antibacterial activity against Escherichia coli. [ABSTRACT FROM AUTHOR]

A symmetrical tetradentate Schiff base, o-HACPHENEN, was prepared by condensation of 1,2-bis(ethylenediamine) with o-hydroxyacetophenone in 1:2 molar ratio. The Schiff base ligand and 1,10-phenanthroline were used for the tailored synthesis of four mixed-ligand complexes, [Mn(o-HACPHENEN)(1,10-phen)] (1), [Fe(o-HACPHENEN)(1,10-phen)]Cl (2), [Co(o-HACPHENEN)(1,10-phen)] (3), and [Ni(o-HACPHENEN)(1,10-phen)] (4). The ligand and complexes were characterized on the basis of elemental analyses, ESI-MS, molar conductance, electronic, FT-IR, 1H-NMR, and 13C-NMR spectra. DFT study was used to optimize the geometry of the investigated compounds. Using Gaussian09 molecular modeling, HOMO-LUMO study, bond lengths, bond angles, molecular electrostatic potential map (MEP), and Mulliken charge were also evaluated. Complexes displayed remarkable catalase-like activity in the disproportion reactions of hydrogen peroxide. The kinetics of the activity were investigated and data are fitted in Lineweaver Burk plot, revealing Michaelis Menten behavior. The catalase activity of ligand and complexes were found in the order 1 > 2 > 4 > 3 > o-HACPHENEN. Compounds were screened for their antibacterial activity against gram-negative bacteria Escherichia coli in comparison to standard drugs. Complexes were more potent than Schiff base. The MIC of complexes was also studied. [ABSTRACT FROM AUTHOR]

Drug resistance in pathogens is a growing global health problem. The development of new drugs is a risky, time-consuming, and expensive process, since only a few got final approval. Organometallic compounds attracted attention due to their promising anticancer activities. In this study, four cyclometallates containing ruthenium and rhodium ions were synthesized from two phenolic azo ligands. These molecules were characterized by elemental analyses, molar conductance measurements, magnetic susceptibility, FT-IR, mass, electronic,1H,13C{1H}, and31P{1H} NMR spectral studies. The general formula for the complexes istrans-[M(PPh3)2(Cl)(L)], where M = Rh or Ru, PPh3 = triphenylphosphine, and L = phenolic azo ligand. All the complexes possess prominent antibacterial activity againstEscherichia coliandMycobacterium tuberculosisas compared to market drugs. The interactions of rhodium derivatives with plasma–protein were also studied. Cyclometalation of a pendant aromatic ring is an example of C–H bond activation. Organometallic compounds were biologically potent and may be helpful for pharmaceutical industries for biological targets. [ABSTRACT FROM PUBLISHER]

Six complexes of Zn(II), Cd(II) and Hg(II) with sulphur containing Schiff base ligand, 1,4-bis((1 H-pyrrol-2-yl)methylene)thiosemicarbazide in 1:1 and 1:2 ratio has been synthesized. Complexes were characterized by molar conductance measurement, elemental analyses, FT-IR, 1H-NMR, and FAB/ESI-Mass. The complexes were used as a single source precursor for the synthesis of ZnS/CdS/HgS nanoparticles by their thermal decomposition in the presence of different surfactants. The precursor: surfactant ratio and temperature plays important role in determining the size of the nanoparticles. The size and morphology of nanoparticles has been ascertained by UV-Vis spectroscopy, XRD measurements and Transmission Electron Microscopy (TEM). Schiff base, complexes and nanoparticles were tested for antibacterial activity and MIC values against E. coli. The complexes were found more potent than the corresponding Schiff bases and nanoparticles. [ABSTRACT FROM AUTHOR]

A bimetallic cuprous complex was accidentally reported, during synthesis of a dinucleating spacer incorporating two 2-chloropyridine units through Sandmayer reaction. The product was characterized by elemental analysis, FAB-Mass, FT-IR, UV, magnetic susceptibility and 1H-NMR spectroscopic method. A possible mechanism is also proposed. [ABSTRACT FROM AUTHOR]

Abstract: Bacteria are amongst the most adaptable organisms on the Earth. The year 2010 was always remarkable for the article published in Lancet Infection Disease by Kumarasamy et al. and the enzyme NDM-1 which makes bacteria resist designed to kill them. Four rhodium(III) chloride complexes with Gatifloxacin have been prepared and characterized by elemental analyses, molar conductance measurements, FTIR, FAB-MS, TGA, 1H NMR and electronic spectral studies. The general formula for complexes are [X]+ fac-[RhCl3(L)(GT)]−; where L = H2O, Dimethylsulfoxide (DMSO), Tetramethylenesulfoxide (TMSO); GT = Gatifloxacin and X = Na or [H(DMSO)2]. All complexes are found to possess prominent antibacterial activity against pathogenic Escherichia coli and Mycobacterium tuberculosis in comparison to Gatifloxacin. [Copyright &y& Elsevier]

The reaction of a new heterocyclic bidentate N containing spacer, (ligand) 5,5′-methylenebis(pyridine) with ruthenium sulphoxide precursors resulted, dinuclear complexes. We herein report three formulations; [{ cis, fac-RuCl2(so)3}2(μ-mbp)].3so; [{ trans, mer-RuCl2(so)32}2(μ-mbp)].3so and [{ trans-RuCl4(so)}2(μ-mbp)]2−[X]2+; where so = dimethyl-sulfoxide/tetramethylenesulfoxide; mbp = 5,5′-methylenebis(pyridine) and [X]+ = [(dmso)2H]+, Na+ or [(tmso)H]+. These complexes were characterized on the basis of elemental analyses, molar conductance measurement, magnetic susceptibility, FT-IR, 1H-NMR, 13C{1H}-NMR, electronic spectroscopy and FAB-Mass spectrometry. Catalytic activity of these complexes has been investigated in hydrolysis of benzonitrile. All the complexes exhibit good antibacterial activity against gram-negative bacteria Escherichia coli in comparison to Chloramphenicol. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of seven ruthenium (II) and ruthenium (III) chloro sulphoxide complexes with 1, 2, 3- benzotriazole are reported. Three different formulations exist: [cis,fac--RuCl2 (so) 3 (btz)]; [trans--RuCl (so) (btz)] and [trans--RuCl4 (so)(btz)] [X]+; where so=dimethylsulphoxide/ tetramethylenesulphoxide; btz = 1, 2, 3-benzotriazole and [X]+ = [(btz)H]+ or Na+. These complexes were characterized by elemental analysis, conductivity measurements, magnetic susceptibility, FT-IR, ¹H-NMR, C13{¹H}-NMR and electronic spectroscopy. Complexes were screened for their antibacterial activity and found more potent than 1, 2, 3-benzotriazole ligand and precursor ruthenium compounds against gram-negative bacteria Escherichia coli. All the samples were compared with antibiotic Chloramphenicol for reference. [ABSTRACT FROM AUTHOR]

A dinucleating spacer incorporating o-phenanthroline has been synthesized and characterized. The reaction of this spacer with ruthenium precursors resulted in formation of dinuclear complexes, [cis,fac-RuCl2(SO)3 (μ-nphen)cis,cis-RuCl2(SO)2], [trans,mer-RuCl2(SO)3 (μ-nphen)trans, cis-RuCl2(SO)2], and [X]+[trans-RuCl4(SO)(μ-nphen)mer-RuCl3(SO)]-, where SO = dimethylsulfoxide/tetramethylenesulfoxide, nphen = 5-nitro-o-phenanthroline, and X+ = [(dmso)2H]+, Na+, and [(tmso)H]+. These complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibility, FT-IR, FAB-Mass, 1H-NMR, 13C{1H}-NMR, and electronic spectroscopy. [trans,mer-RuCl2(dmso)3(μ-nphen)trans,cis-RuCl2(dmso)2] was also characterized on the basis of 1H-1H COSY NMR. The coordination of one ruthenium is through heterocyclic nitrogen of the o-phenanthroline and the second is through the oxygen of the nitrito group. Catalytic activity of these complexes has been investigated in hydrolysis of benzonitrile. All the complexes possess antibacterial activity against Escherichia coli and are compared to Chloramphenicol. [ABSTRACT FROM AUTHOR]

Complexes of MM'(SeCN)4, (M = Co2+, Ni2+; M' = Cd2+, Zn2+) with the Schiff base, N,N'-bis(2-chlorobenzylidene)ethylenediamine have been synthesized and characterized by elemental analysis, molar conductance, magnetic moment, FTIR, 1H-NMR, 13C{1H}-NMR and electronic spectroscopy. The catalytic activity of these complexes for hydrolysis of benzonitrile has been investigated. The complexes have also been investigated for antibacterial activity against Escherichia Coli and found to exhibit good growth inhibiton. [ABSTRACT FROM AUTHOR]

We report the synthesis of five complexes of three different formulations viz. [cis-RuCl2(4-antp)2], [trans-RuCl2(4-antp)2] and [X]+[trans-RuCl4(4-antp)2]- (X+ = [(DMSO)2H]+, Na+, or [(TMSO)H]+ and 4-antp = 4-aminoantipyrine) from different routes. These complexes were characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility, electronic spectra, FTIR, 1H-NMR and 13C{1H}-NMR spectroscopy. Complexes were screened for antibacterial activity and found to be potent against gram negative bacteria Escherichia coli. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of anionic and neutral dimers of three general formulations viz. [{cis-RuCl2(SO)3}2(2-ClBENEN)]; [{trans-RuCl2(SO)3}2(2-ClBENEN)] and [image omitted][{RuCl4(SO)}2(2-ClBENEN)]2-; where SO = dimethylsulphoxide/tetramethylenesulphoxide; X = [(dmso)2H]+; Na+; [(tmso)H]+; and 2-ClBENEN = N,N'-bis(2-chlorobenzylidene)-1,2-ethylenediamine. These complexes were characterized on the basis of elemental analysis, magnetic susceptibility, electronic, FTIR, 1H-NMR and 13C{1H}NMR spectroscopy. These complexes are rare examples where a Schiff-base ligand serves as a spacer group. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of seven ruthenium(II) and ruthenium(III) complexes of sulfoxide with 2-aminobenzothiazole are reported. Three different formulations exist: [cis,cis,cis-RuCl2(SO)2(2-abtz)2] and [trans,trans,trans-RuCl2(SO)2(2-abtz)2] and [trans-RuCl4(SO)(2-abtz)]- [X]+ (where SO = dimethyl sulfoxide (dmso) or tetramethylenesulfoxide (tmso); 2-abtz = 2-aminobenzothiazole and [X]+ = [H(abtz)]+, [Na+]. These complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibility, FTIR, 1H NMR, 13C{1H} NMR and electronic spectroscopy. Some of the complexes were screened for their antibacterial activity and are found to be potent against the gram negative bacteria Escherichia coli. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of seven ruthenium(II) and ruthenium(III) complexes of sulphoxide with 2-aminobenzimidazole are reported. Three different formulations exist; [cis-RuCl2(SO)3(2-ABZ)]; [trans-RuCl2(SO)3)(2-ABZ)]; and [trans-RuCl4(SO)(2-ABZ (where SO = dimethylsulphoxide(DMSO)/tetramethylenesulphoxide(TMSO); 2-ABZ = 2-aminobenzimidazole). These complexes are characterized by elemental analysis, conductivity magnetic susceptibility, 1H-NMR, 13C{1H}-NMR and electronic spectroscopy. [ABSTRACT FROM AUTHOR]

A wide range of methods have been executed for the removal of synthetic dyes from water waste; to decrease their harmful impact on the environment. Photocatalytic degradation is proved to be the most effective approach for the removal of dyes from an aqueous solution. Therefore, we have synthesized metal sulphide quantum dots through the thermal decomposition of complexes. The reaction of metal(II)chloride salts of zinc, cadmium and mercury with 1-((thiophen-2-yl)methylene)-thiosemicarbazide (1-TMT) in 1:1 and 1:2 ratio results three neutral 1, 3 and 5, [M(1-TMT)Cl2] and three ionic complexes 2, 4 and 6, [M(1-TMT)2]Cl2; Where M = Zn for 1 and 2, Cd for 3 and 4, and Hg for 5 and 6. These complexes 1–6 were characterized with elemental analysis and different spectroscopic methods. These complexes were used as single source precursor for the synthesis of metal sulphide (ZnS/CdS/HgS) by thermal decomposition in presence of different surfactants. The precursor surfactant ratio and temperature play an important role in determining the size of the nanoparticles. Several characterization tools were employed to study the phase structures, morphologies, and optical properties of the samples viz. XRD, TEM. The nanoparticles obtained from thermal degradation of these complexes were screened for their catalytic potential on photocatalytic degradation of Congored dye and reported maximum efficiency with CdS nanoparticles at alkaline pH. The Schiff Base (1-TMT), 1–6 and metal sulphide nanoparticles were also screened for antibacterial activity and MIC values against Escherichia coli. The complexes were found more potent than the corresponding Schiff Bases and nanoparticles. [ABSTRACT FROM AUTHOR]