scholarly journals Spectral, NLO, Fluorescence, and Biological Activity of Knoevenagel Condensate of β-Diketone Ligands and Their Metal(II) Complexes

2011 ◽  
Vol 2011 ◽  
pp. 1-8
Author(s):  
S. Sumathi ◽  
C. Anitha ◽  
P. Tharmaraj ◽  
C. D. Sheela
Keyword(s):  
Metal Complexes ◽  
Second Harmonic ◽  
Biological Activities ◽  
Analytical Data ◽  
Structural Features ◽  
Considerable Effect ◽  
Molar Conductance ◽  
Spectral Studies ◽  
Planar Geometry

Transition metal complexes of various acetylacetone-based ligands of the type ML (where M=  Cu(II), Ni(II), Co(II); L=  3-(aryl)-pentane-2,4-dione) have been synthesized. The structural features have been derived from their elemental analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, H1NMR, mass and ESR spectral studies. Conductivity measurements reveal that all the complexes are nonelectrolytic in nature. Spectroscopic and other analytical data of the complexes suggest square planar geometry for copper(II), cobalt(II), and nickel(II) complexes of 3-(3-phenylallylidene)pentane-2,4-dione and octahedral geometry for other metal(II) complexes. The redox behaviors of the copper(II) complexes have been studied by cyclic voltammetry. The free ligands and their metal complexes have been screened for their in vitro biological activities against bacteria and fungus. The metal(II) complexes are found to possess increased activities compared to those of the free ligands. All synthesized compounds may serve as potential photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic generation (SHG) efficiency of the ligands was found to have considerable effect compared to that of urea and KDP.

scholarly journals Physico-chemical and biological studies of Cu(II), Co(II) and Ni(II) complexes of an N4 coordinating ligand derived from diacetylbisethylenediamine and benzoic acid

2012 ◽  
Vol 77 (5) ◽  
pp. 627-637 ◽  
Author(s):  
Pal Singh ◽  
Nanda Srivastava
Keyword(s):  
Benzoic Acid ◽  
Metal Complexes ◽  
Magnetic Moment ◽  
Biological Activities ◽  
Molar Conductance ◽  
Planar Geometry ◽  
Cyclic Voltammetric Study ◽  
Biological Studies ◽  
Antibacterial And Antifungal

Mononuclear metal complexes of the type [ML1]Cl2 (where, M = = Cu(II), Co(II) or Ni(II) and L1 = ligand) were synthesized by the reaction of a new N4 coordinating ligand, derived from diacetylbisethylenediamine with benzoic acid, and the corresponding hydrated metal chloride salts. The metal complexes were characterized by elemental analysis, melting point determination, molar conductance and magnetic moment measurements, IR, UV-Vis, 1H- and 13C-NMR, and ESR spectroscopy. The ligand and all the metal complexes were stable in the solid state at room temperature. From the analytical and spectroscopic investigations, the stoichiometry of the complexes was found to be 1:1 (metal:ligand). Based on the electronic spectra and magnetic moment data, the metal complexes had a square planar geometry. The molar conductance values show the 1:2 electrolytic nature of the metal complexes. A cyclic voltammetric study of the Cu(II) metal complex has also performed, which showed one electron quasi-reversible reduction around -0.92 to -1.10 V. In vitro biological activities of the ligand and metal complexes was checked against two bacteria Bacillus subtilis and Escherichia coli and two fungi Aspirgillus niger and A. flavus which showed the antibacterial and antifungal properties of the ligand and its metal complexes.

scholarly journals Synthesis, Thermal Characterization and in vitro Antibacterial Assessment of Co(II) and Cd(II) Complexes of Schiff Base Derived from Amoxicillin and Thiophene-2-carbaldehyde

2019 ◽  
Vol 31 (4) ◽  
pp. 951-959 ◽  
Author(s):  
N.K. Chaudhary ◽  
B. Guragain
Keyword(s):  
Metal Complexes ◽  
Biological Activities ◽  
Geometry Optimization ◽  
Thermal Characterization ◽  
Molar Conductance ◽  
Sem Analysis ◽  
Biological Data ◽  
Spectral Studies ◽  
Tetrahedral Geometry

A novel AMXTC2 ligand was prepared by simultaneous stirring and refluxing of an equimolar mixture of amoxicillin and thiophene-2-carbaldehyde in methanol and was further used to synthesize metal complexes by metalation with cobalt and cadmium salts, taking ligand metal ratio 2:1. They were characterized by elemental microanalysis, FT-IR, mass, UV-visible, 1H NMR, thermal analysis, magnetic moment and molar conductance measurements. The coordination sites in the ligand were verified by their comparative and extensive spectral studies. The detailed exploration of the data suggested octahedral geometry for Co-AMXTC2 and tetrahedral geometry for Cd-AMXTC2 complexes. The thermodynamic and kinetic parameters such as E*, ΔH*, ΔS* and ΔG* of various decomposition steps were calculated from TGA curves using the Coats-Redfern method. The molar conductivity data suggested non-electrolytic nature of the complexes. SEM analysis was done to observe their surface morphology. The geometry optimization of the proposed molecular structure of the complexes was achieved by running MM2 calculation in Gaussian supported Cs-ChemOffice Ultra-11 program software. The biological activities had been evaluated in vitro against E. coli, K. pneumonia, P. vulgaris and S. aureus pathogens in order to assess their antibacterial potency. The biological data revealed better growth inhibitory action of the ligand and metal complexes with bacterial pathogens.

scholarly journals Synthesis, Spectroscopic Characterization, and Biological Activities of Metal Complexes of 4-((4-Chlorophenyl)diazenyl)-2-((p-tolylimino)methyl)phenol

2013 ◽  
Vol 2013 ◽  
pp. 1-12
Author(s):  
C. Anitha ◽  
C. D. Sheela ◽  
P. Tharmaraj ◽  
V. V. Hema
Keyword(s):  
Schiff Base ◽  
Second Harmonic ◽  
Biological Activities ◽  
Potassium Dihydrogen Phosphate ◽  
Spectroscopic Characterization ◽  
Structural Features ◽  
Schiff Base Complexes ◽  
Spectral Studies ◽  
Planar Geometry ◽  
Dihydrogen Phosphate

Azo Schiff base complexes of VO(II), Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized from 4-((4-chlorophenyl)diazenyl)-2-((p-tolylimino)methyl)phenol (CDTMP). The nature of bonding and the structural features of the complexes have been deduced from elemental analysis, molar conductance, magnetic susceptibility measurements, IR, UV-Vis,1H-NMR, EPR, mass, SEM, and fluorescence spectral studies. Spectroscopic and other analytical studies reveal square-planar geometry for copper, square-pyramidal geometry for oxovanadium, and octahedral geometry for other complexes. The EPR spectra of copper(II) complex in DMSO at 300 K and 77 K were recorded, and its salient features are reported. Antimicrobial studies against several microorganisms indicate that the complexes are more potent bactericides and fungicides than the ligand. The electrochemical behavior of the copper(II) complex was studied by cyclic voltammetry. All the synthesized compounds can serve as potential photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic conversion efficiency of the synthesized azo Schiff base was found to be higher than that of urea and KDP (potassium dihydrogen phosphate). SEM image of copper(II) complex implies the crystalline state and surface morphology of the complex.

scholarly journals Synthesis, Characterization, and Biological Activity of Some Transition Metal Complexes Derived from Novel Hydrazone Azo Schiff Base Ligand

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
C. Anitha ◽  
S. Sumathi ◽  
P. Tharmaraj ◽  
C. D. Sheela
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Schiff Base Ligand ◽  
Second Harmonic ◽  
Biological Activities ◽  
Diffusion Method ◽  
Spectral Studies ◽  
Planar Geometry ◽  
Conductivity Measurements ◽  
Tetrahedral Geometry

A series of metal(II) complexes ML where M = VO(II), Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized from azo Schiff base ligand (N′E)-N′-(5-((4-chlorophenyl)diazenyl)-2-hydroxybenzylidene)-2-hydroxybenzohydrazide and characterized on the basis of elemental analyses, electronic, IR, and 1H NMR spectra, magnetic susceptibility and also by aid of scanning electron microscopy (SEM), X-ray powder diffraction, fluorescence spectral studies, and molar conductivity measurements. Conductivity measurements reveal that the complexes are nonelectrolytes. Spectroscopy and other analytical studies reveal distorted square planar geometry for copper, square-pyramidal geometry for oxovanadium, and tetrahedral geometry for other complexes. Redox behavior of the copper(II) complex has been studied with cyclic voltammetry, and the biological activities of the ligand and metal complexes have been studied against several microorganisms by the well diffusion method. All synthesized compounds can serve as potential photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic generation (SHG) efficiency of the ligand was measured and found to be higher than that of urea and KDP. The SEM image of the copper(II) complex implies that the size of the particles is 50 nm.

scholarly journals THE METAL COMPLEXES OF NOVEL SCHIFF BASE CONTAINING ISATIN: CHARACTERIZATION, ANTIMICROBIAL, ANTIOXIDANT AND CATALYTIC ACTIVITY STUDY

2019 ◽  
pp. 206-210
Author(s):  
VAIRALAKSHMI M ◽  
PRINCESS R ◽  
JOHNSON RAJA S
Keyword(s):  
Catalytic Activity ◽  
Metal Complexes ◽  
1H Nmr ◽  
Metal Ion ◽  
Analytical Data ◽  
Free Ligand ◽  
Molar Conductance ◽  
Diffusion Method ◽  
Spectral Studies ◽  
Standard Drug

Objectives: The aim of our work was to synthesize novel mixed ligand-metal complexes and evaluation of antimicrobial, antioxidant assay, and analysis of catalytic oxidation of cyclohexane. Methods: The complexes were characterized by means of various physicochemical techniques such as elemental analysis, molar conductance, magnetic susceptibility, infrared (IR), electronic absorption, 1H NMR (proton magnetic resonance), and mass spectral studies. The antimicrobial screening study was done by disc diffusion method. The catalytic activity of the complexes was observed in the oxidation of cyclohexane using eco-friendly hydrogen peroxide as oxidant. Results: On comparing the 1H NMR and IR spectral data of free ligand and its complexes, it was found to be azomethine (CH=N) proton which is formed in the free ligand. During complexation, the azomethine proton is coordinated to the metal ion and the phenolic oxygen is coordinated to the metal ion by deprotonation. The analytical data and mass spectra of the ligand and the complexes confirm the stoichiometry of metal complexes as being of the (MLY)Cl type and the metal to ligand ratio is 1:1. The antimicrobial, antioxidant, and catalytic potential were evaluated and the result shows the better activity of the complexes than the ligand. Conclusion: It was found to be copper(II) and zinc(II) complexes which are effective against all the bacteria when compared to standard drug streptomycin. Copper(II) complex was found to be effective antibacterial agent against Aspergillus niger and Aspergillus flavus in comparison to the standard drug Nystatin. The zinc complex exhibited good catalytic activity.

scholarly journals Synthesis and Spectral Studies of 4,4′-(Hydrazine-1,2-diylidenedimethylylidene)-bis-(2- methoxyphenol) and Its Transition Metal Complexes with Promising Biological Activities

2020 ◽  
Vol 32 (7) ◽  
pp. 1768-1772
Author(s):  
Anita Rani ◽  
Manoj Kumar ◽  
Hardeep Singh Tuli ◽  
Zahoor Abbas ◽  
Vinit Prakash
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Schiff Base Ligand ◽  
Biological Activities ◽  
Condensation Reaction ◽  
Analytical Techniques ◽  
Spectral Studies

The study describes the synthesis, characterization and biological activity of a novel Schiff base ligand and its transition metal complexes. The Schiff base ligand was obtained by a condensation reaction between 4-hydroxy-3-methoxybenzaldehyde (p-vanillin) and hydrazine hydrate using ethanol as solvent. A new series of Ni(II) and Fe(III) complexes were also derived by reaction of prepared Schiff base ligand with NiCl2 and FeCl3. Both the ligand and its metal complexes were characterized by solubility, melting point and elemental analysis. These compounds were further identified by analytical techniques, FTIR, NMR and mass spectrometry. The ligand and its transition metal complexes were also subjected to in vitro biological activities i.e. antimicrobial, antiangiogenic and DNA photo cleavage. For antimicrobial activity compounds were tested against two strains of bacteria and two strains of fungi. Different concentrations of prepared compounds were treated with fertilized chicken eggs and plasmid DNA to find out antiangiogenic and DNA photocleavage activity, respectively.

scholarly journals Synthesis, Spectroscopic, and Antimicrobial Studies on Bivalent Nickel and Copper Complexes of Bis(thiosemicrbazone)

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
Sulekh Chandra ◽  
Smriti Raizada ◽  
Monika Tyagi ◽  
Archana Gautam
Keyword(s):  
Metal Complexes ◽  
Metal Ion ◽  
Copper Complexes ◽  
Free Ligand ◽  
Antimicrobial Properties ◽  
Molar Conductance ◽  
Spectral Studies ◽  
Central Metal ◽  
Antimicrobial Studies

A series of metal complexes of Cu(II) and Ni(II) having the general composition[M(L)X2]with benzil bis(thiosemicarbazone) has been prepared and characterized by element chemical analysis, molar conductance, magnetic susceptibility measurements, and spectral (electronic, IR, EPR, mass) studies. The IR spectral data suggest the involvement of sulphur and azomethane nitrogen in coordination to the central metal ion. On the basis of spectral studies, an octahedral geometry has been assigned for Ni(II) complexes but a tetragonal geometry for Cu(II) complexes. The free ligand and its metal complexes have been tested in vitro against a number of microorganisms in order to assess their antimicrobial properties.

scholarly journals Synthesis, Characterization, Antimicrobial, DNA Cleavage, andIn VitroCytotoxic Studies of Some Metal Complexes of Schiff Base Ligand Derived from Thiazole and Quinoline Moiety

2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
Nagesh Gunvanthrao Yernale ◽  
Mruthyunjayaswamy Bennikallu Hire Mathada
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Schiff Base Ligand ◽  
Dna Cleavage ◽  
Biological Activities ◽  
Artemia Salina ◽  
Spectral Studies ◽  
Antibacterial And Antifungal Activities ◽  
Pyramidal Geometry

A novel Schiff base ligandN-(4-phenylthiazol-2yl)-2-((2-thiaxo-1,2-dihydroquinolin-3-yl)methylene)hydrazinecarboxamide(L)obtained by the condensation ofN-(4-phenylthiazol-2-yl)hydrazinecarboxamide with 2-thioxo-1,2-dihydroquinoline-3-carbaldehyde and its newly synthesized Cu(II), Co(II), Ni(II), and Zn(II) complexes have been characterized by elemental analysis and various spectral studies like FT-IR,1H NMR, ESI mass, UV-Visible, ESR, TGA/DTA, and powder X-ray diffraction studies. The Schiff base ligand(L)behaves as tridentate ONS donor and forms the complexes of type [ML(Cl)2] with square pyramidal geometry. The Schiff base ligand(L)and its metal complexes have been screenedin vitrofor their antibacterial and antifungal activities by minimum inhibitory concentration (MIC) method. The DNA cleavage activity of ligand and its metal complexes were studied using plasmid DNA pBR322 as a target molecule by gel electrophoresis method. The brine shrimp bioassay was also carried out to study thein vitrocytotoxicity properties for the ligand and its metal complexes againstArtemia salina. The results showed that the biological activities of the ligand were found to be increased on complexation.

scholarly journals Studies on Inclusion Complexes of β-Cyclodextrin with Some Metal Complexes of Isatinylsemicarbazone and Isatinylthiosemicarbazone

2020 ◽  
Vol 32 (12) ◽  
pp. 3197-3202
Author(s):  
Rajeev Kumar ◽  
Sanjay Kumar ◽  
Madhu Bala
Keyword(s):  
Magnetic Susceptibility ◽  
Metal Complexes ◽  
Inclusion Complexes ◽  
Analytical Data ◽  
Molar Conductance ◽  
Spectral Studies ◽  
Tetrahedral Geometry ◽  
Solid States ◽  
Spectral Bands ◽  
Infrared Spectral

The complexes of Co(II), Ni(II), Zn(II) and Cd(II) with isatinylsemicarbazone (IstscabH) and isatinylthiosemicarbazone (IsttscabH) of composition ML2·2H2O [M = Co(II) or Ni(II) and LH = IstscabH or IsttscabH] and ML2 [M = Zn(II) or Cd(II) and LH = IstscabH or IsttscabH] have been synthesized and their antibacterial activity has been investigated. Their inclusion complexes with β-cyclodextrin (β-CD) having composition [ML2(β-CD)·2H2O] or M(C60H88N8O39S2)], [M = Co(II) or Ni(II) and LH = IstscabH or IsttscabH] and [ML2(β-CD) or M(C60H84N6O-37S2)], [M = Zn(II) or Cd(II) and LH = IstscabH or IsttscabH] have also been isolated in solid states. All the synthesized metal complexes have been characterized by analytical data, molar conductance, magnetic susceptibility, electronic and infrared spectral studies. The tetrahedral geometry for Zn(II) and Cd(II) and octahederal geometry for Co(II) and Ni(II) have been assigned on the basis of magnetic susceptibility, UV electronic transitions and IR spectral bands assignments. The structures are retained in inclusion products. A biological activity of Schiff bases, their metal complexes and inclusion products for bacteria Escherichia. coli, Bacillus subtilis and Staphylococcus aureus have been screened and activity explained.

scholarly journals Synthesis and Characterization of New Lead(II) and Organotin(IV) Complexes of Schiff Bases Derived from Histidine and Methionine

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Har Lal Singh ◽  
J. B. Singh
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Analytical Data ◽  
Molar Conductance ◽  
Molar Ratio ◽  
Azomethine Nitrogen ◽  
Spectral Studies ◽  
Tetrahedral Geometry ◽  
H Nmr ◽  
Carboxylate Oxygen

New Schiff base (HL) ligand is prepared via condensation of isatins and amino acids in 1:1 molar ratio. Metal complexes are prepared and characterized by elemental analysis, molar conductance, electronic, infrared, and multinuclear magnetic resonance (1H NMR, 13C NMR, and 119Sn NMR). The analytical data showed that the ligand acts as bidentate toward metal ions via azomethine nitrogen and carboxylate oxygen by a stoichiometric reaction of metal : ligand (1 : 2) to from metal complexes (Pb(II)(L)2 and Bu2Sn(L)2, where L is the Schiff base ligands of histidine and methionine). The conductivity values between 15 and 25 Ω−1cm2 mol−1 in DMF imply the presence of nonelectrolyte species. On the basis of the above spectral studies, distorted octahedral and tetrahedral geometry have been proposed for the resulting organotin(IV) and lead(II) complexes.

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