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Synthesis, characterization and thermal study of some transition metal complexes of an asymmetrical tetradentate Schiff base ligand  [PDF]
ACHUT S. MUNDE,AMARNATH N. JAGDALE,SARIKA M. JADHAV,TRIMBAK K. CHONDHEKAR
Journal of the Serbian Chemical Society , 2010,
Abstract: Complexes of Cu(II), Ni(II), Co(II), Mn(II) and Fe(III) with an asymmetric tetradentate Schiff base ligand derived from dehydroacetic acid, 4-methyl-o-phenylenediamine and salicylic aldehyde were synthesized and characterized by elemental analysis, conductometry, magnetic susceptibility, UV–Vis, IR, 1H-NMR spectroscopy, X-ray diffraction analysis of powdered samples and thermal analysis, and screened for antimicrobial activity. The IR spectral data suggested that the ligand behaves as a dibasic tetadentate ligand towards the central metal ion with an ONNO donor atoms sequence. From the microanalytical data, the stoichiometry of the complexes 1:1 (metal:ligand) was found. The physico-chemical data suggested square planar geometry for the Cu(II) and Ni(II) complexes and octahedral geometry for the Co(II), Mn(II) and Fe(III) complexes. The thermal behaviour (TGA/DTA) of the complexes was studied and kinetic parameters were determined by Horowitz–Metzger and Coats–Redfern methods. The powder X-ray diffraction data suggested a monoclinic crystal system for the Co(II), Mn(II) and Fe(III) complexes. The ligand and their metal complexes were screened for antibacterial activity against Staphylococcus aureus and Escherichia coli and fungicidal activity against Aspergillus niger and Trichoderma viride.
Synthesis and Antibacterial Studies of Metal Complexes of Cu(II), Ni(II) and Co(II) with Tetradentate Ligand  [PDF]
Alyaa Abdulhasan Abdulkarem
Journal of Biophysical Chemistry (JBPC) , 2017, DOI: 10.4236/jbpc.2017.82002
Abstract: The new metal complexes of Cu(II), Ni(II) and Co(II) with the new ligand derived from isatine and 1,2-diaminocyclohexane were synthesized and biologically screened. The synthesized complexes and ligand were characterized by spectroscopic FT-IR, UV-VIS, 1H-NMR and elemental analyses. The ligand and complexes were screened for their antibacterial activities against three different strains, namely E. coli, P. aeruginosa and S. aureus. In particular, the Co(II) and Cu-complexes exhibited excellent antibacterial activities compared to the reference compound.
Synthesis and characterization of a tetraaza macrocyclic ligand and its cobalt(II), nickel(II) and copper(II) complexes  [PDF]
SULEKH CHANDR,MONIKA TYAG,SWATI AGARWAL
Journal of the Serbian Chemical Society , 2010,
Abstract: Co(II), Ni(II), and Cu(II) complexes with a tetradentate nitrogen donor [N4] macrocyclic ligand, viz. 6,15-dimethyl-8,17diphenyl-7,16-dihydrodibenzo[b,i][1.4.8.11]tetraazacyclotetradecine, were synthesized. Their structures were determined based on elemental analyses, molar conductance and magnetic susceptibility measurements, and IR, 1H-NMR (ligand) and electronic spectral studies. Based on analytical and molar conductance data, the complexes may be formulated as [M(L)Cl2] and [M’(L)]Cl2 (where M = Co(II) and Cu(II), and M’ = Ni(II)) due to their non-electrolytic and 1:2 electrolytic nature. Based on spectral studies, an octahedral geometry was assigned for the Co(II) complex, whereas square-planar and tetragonal geometry were proposed for the Ni(II) and Cu(II) complexes, respectively. The synthesized ligand and its complexes were screened for fungicidal activity against two pathogenic fungi (i.e., Fusarium moniliformae and Rhizoctonia solani) to assess their growth inhibiting potential.
Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) Mixed Ligand Complexes of Theophylline and Cyanate: Synthesis and Spectroscopic Characterization  [cached]
Shayma Ahmed Shaker
Modern Applied Science , 2009, DOI: 10.5539/mas.v3n12p88
Abstract: New mixed ligand complexes were synthesized between theophylline and cyanate to give complexes with general formula [M(Tp)4Y2] where Tp= theophylline, Y= cyanate ion and M=Co(II), Ni(II),Cu(II), Zn(II) and Cd(II). The resulting products were found to be crystallined which have been characterized using UV-Visible spectroscopic properties and Infrared spectra. Elemental analyses were performed using (C, H, N) and atomic absorption technique. The magnetic susceptibility and the conductivity for the complexes were also measured. The present results suggested the octahedral configuration for the metal complexes.
SYNTHESIS AND STRUCTURAL STUDIES OF MIXED LIGAND COMPLEXES OF Mn(II),Cu(II)WITHOXYGEN AND NITROGEN DONAR LIGANDS
P.R.SHIRODE
Indian Streams Research Journal , 2012,
Abstract: The mixed ligand complexes of the type [M(L1)(L2)]Cl2 (whereM= Mn(II)and Cu(II) and L1=Acetophenone emicarbazone,L2=Benzaldehydeemicarbazone,cyclohexanonesemicarbazone,acetonesemicarbazone)have been synthesized by the reactions of metal chlorides with two different semicarbazone compounds in 1:1:1 molar ratios. The resulting complexes have been characterized on the basis of elemental analysis, magnetic measurement, IR and electronic spectra, conductivity measurement. The metal complexes shows ratio 1:1:1 with metal ligand L1 and ligand L2.The ligands acts as bidentate ligands and are bonded through oxygen and nitrogen to metal ion. The two co-ordinationpositions are occupied by two water molecules. The complexes have octahedral structure.
Synthesis, Characterization and Antimicrobial Screening Mixed-Ligand Cu(II) and Zn(II) Complexes; DNA Binding Studies on Cu(II) Complex  [PDF]
Omar H. Al-Obaidi
Open Journal of Inorganic Non-metallic Materials (OJINM) , 2012, DOI: 10.4236/ojinm.2012.24007
Abstract: Several mixed ligand Cu(II), Zn(II) complexes using (benzylidenethiourea) (obtained by the condensation of benzaldehyde and thiourea) as the primary ligand and (acetamide or thioacetamide) as an additional ligand were synthesized and characterized analytically and spectroscopically, magnetic susceptibility and molar conductance measurements ,as well as by UV-Vis. and IR spectroscopy. The interaction of the complexes with calf thymus (CT)DNA was studied using absorption spectra, while the concentration of DNA in gel electrophoresis remained constant at 10 μl. They exhibit absorption hypochromicity increased during the binding of the complexes to calf thymus DNA. The complexes show enhanced antimicrobial activities complexes with the free ligand. A theoretical treatment of the formation of complexes in the gas phase was studied, this was done using the HYPERCHEM-6 program for the Molecular mechanics and Semi-empirical calculations.
INVESTIGATIONS ON NUCLEASE ACTIVITY OF TRANS MIXED LIGAND- COPPER(II) COMPLEXES WITH ORTHO SUBSTITUTED AROMATIC OXIMES AND HETEROCYCLIC BASES
SURENDRA BABU,M.S; KRISHNA,PITCHIKA.G; HUSSAIN REDDY,K; PHILIP,G.H;
Journal of the Chilean Chemical Society , 2009, DOI: 10.4067/S0717-97072009000400003
Abstract: mixed ligand complexes of copper(ii) with salicyladoxime (sao), 2-hydroxy acetophenone oxime (hao) as primary ligands and pyridine( py), imidazole (im) as secondary ligands have been synthesized and characterized by molar conductivity, magnetic moments, electronic, ir and esr spectral data. cyclic voltammetric studies show quasi-reversible reduction attributable to cu2+/ cu+. the binding interactions between metal complexes and calf thymus dna have been investigated by using uv -visible titrations and cyclic voltammetry studies. the cleavage activity of complexes was carried out on double-stranded pbr322 circular plasmid dna by using gel electrophoresis. all complexes show increased nuclease activity in the presence of oxidant (h202). the nuclease activity of mixed ligand complexes are compared with that of the parent copper(ii) complexes. controlled experiments suggest that the complexes cleave dna predominantly via an oxidative mechanism.
COBALT(II), Ni(II), Cu(II), Zn(II), CD(II), Hg(II), U0(2)(VI) AND th(IV) COMPLEXES FROM ONNN SCHIFF BASE LIGAND
REDDY. K,RAMA KRISHNA; SUNEETHA,P; KARIGAR,C. S; MANJUNATH,N. H; MAHENDRA,K. N;
Journal of the Chilean Chemical Society , 2008, DOI: 10.4067/S0717-97072008000400003
Abstract: a new tetradentate schiff base, 3-[(z)-2-piperazin-l-yl-ethylimino]-l, 3-dihydro indol-2-one was synthesized by the condensation of isatin(indole-2,3-dione) with l-(2-aminoethyl)piperazine(aep). its complexes with co(ii), ni(ii), cu(ii), zn(ii), cd(ii), hg(ii), u02(vi) and th(iv) have been synthesized and characterized by microanalysis, conductivity, uv-visible, ft-ir, 'h nmr, tga and magnetic susceptibility measurements. the complexes have 1:1 metal to ligand stoichiometry. the complexes of cu(ii) and th(iv) are 1:1 electrolytes whereas the complexes of co(ii), ni(ii), zn(ii), cd(ii), hg(ii) and u02(vi) are nonelectrolytes. itie spectral data revealed that the ligand acts as a neutral tetradentate, coordinating through the azomethine nitrogen, two piperazine nitrogen atoms and carbonyl oxygen. octahedral geometry for co(ii), ni(ii), cu(ii), zn(ii), cd(ii) and hg(ii) complexes and a coordination number of 8 for u02(vi) and th(iv) complexes are proposed. the ligand and its metal complexes were screened for antibacterial activity against bacillus subtilis, staphylococcus aureus (s. aureus), escherichia coli (e. coli) and pseudomonas aeruginosa and the complexes are more potent bactericides than the ligand. the anthelmentic activity of the ligand and its complexes against earthworms was also tested.
COBALT(II), Ni(II), Cu(II), Zn(II), CD(II), Hg(II), U0(2)(VI) AND th(IV) COMPLEXES FROM ONNN SCHIFF BASE LIGAND  [cached]
RAMA KRISHNA REDDY. K,P SUNEETHA,C. S KARIGAR,N. H MANJUNATH
Journal of the Chilean Chemical Society , 2008,
Abstract: A new tetradentate Schiff base, 3-[(Z)-2-piperazin-l-yl-ethylimino]-l, 3-dihydro indol-2-one was synthesized by the condensation of isatin(Indole-2,3-dione) with l-(2-aminoethyl)piperazine(AEP). Its complexes with Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), U0(2)(VI) and Th(IV) have been synthesized and characterized by microanalysis, conductivity, UV-visible, FT-IR, 'H NMR, TGA and magnetic susceptibility measurements. The complexes have 1:1 metal to ligand stoichiometry. The complexes of Cu(II) and Th(IV) are 1:1 electrolytes whereas the complexes of Co(II), Ni(II), Zn(II), Cd(II), Hg(II) and U0(2)(VI) are nonelectrolytes. ITie spectral data revealed that the ligand acts as a neutral tetradentate, coordinating through the azomethine nitrogen, two piperazine nitrogen atoms and carbonyl oxygen. Octahedral geometry for Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) complexes and a coordination number of 8 for U0(2)(VI) and Th(IV) complexes are proposed. The ligand and its metal complexes were screened for antibacterial activity against Bacillus subtilis, Staphylococcus aureus (S. aureus), Escherichia Coli (E. Coli) and Pseudomonas aeruginosa and the complexes are more potent bactericides than the ligand. The anthelmentic activity of the ligand and its complexes against earthworms was also tested.
Spectroscopic and biological approach in the characterization of Cr(III), Mn(II) and Co(II) complexes with a novel hexaaza-macrocyclic ligand derived from semicarbazide  [PDF]
SULEKH CHANDRA,ARCHANA GAUTAM
Journal of the Serbian Chemical Society , 2009,
Abstract: Complexes of Cr(III), Mn(II) and Co(II) with a novel 5,7,12,14-tetraphenyl-1,2,4,8,10,11-hexaazacyclotetradecane-3,9-dione macrocyclic ligand, THTD (L), were synthesized and characterized by elemental analysis, molar conductance and magnetic susceptibility measurements, as well as by mass, 1H-NMR, IR, electronic and EPR spectral studies. Based on the spectral studies, an octahedral geometry was assigned for the Cr(III), Mn(II) and Co(II) complexes. The ligand and its complexes were screened in vitro against some species of bacteria and plant pathogenic fungi. The metal complexes were found to be more active antimicrobial agents than the free ligand from which they were derived.
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