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

Author(s):  
VAIRALAKSHMI M ◽  
PRINCESS R ◽  
JOHNSON RAJA S

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.

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
Sulekh Chandra ◽  
Smriti Raizada ◽  
Monika Tyagi ◽  
Archana Gautam

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.


2009 ◽  
Vol 2009 ◽  
pp. 1-6 ◽  
Author(s):  
Sulekh Chandra ◽  
Shikha Parmar ◽  
Yatendra Kumar

A series of metal complexes of Zn(II) and Hg(II) having the general composition [where L = 2-formylpyridine thiosemicarbazone; M = Zn(II) and Hg(II); X = , and ] have been prepared and characterized by elemental chemical analysis, molar conductance, and spectral (IR and mass) studies. The IR spectral data suggests the involvement of sulphur and azomethane nitrogen in coordination to the central metal ion. On the basis of spectral studies, a tetrahedral geometry has been assigned for Zn(II) and Hg(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.


2021 ◽  
Vol 6 (4) ◽  
pp. 243-249
Author(s):  
B.R. Chaitanya Kumar ◽  
K. Sudhakar Babu ◽  
J. Latha

A pyridine derivative 2-((E)-1-(2-hydrazinyl-4-methyl-6-phenyl-pyridine-3-carboyl)ethyl)pyridine-4- carbonitrile (CPHPC) ligand and its 3d-metal(II) complexes has been synthesized (where [M = Co(II), Ni(II) and Cu(II)]. The physico-chemical, analytical data, UV-Vis, FT-IR, 1H NMR and ESR spectrum methods were used to characterize all of the synthesized complexes. Spectral investigations of metal(II) complexes revealed that the metal ion is surrounded by an octahedral geometry. Low conductance values indicated that the metal(II) complexes behave as non-electrolyte. The cytotoxic activity on lung cancer cell lines and hepatic cancer cell lines A549 and HepG2, respectively, with the ligand and their metal complexes were tested with MTT assay. The ligand and its metal complexes were tested for diverse harmful bacterial strains using the agar well diffusion method on Gram-negative bacteria such as Pseudomonas desmolyticum, Escherichia coli and Klebsiella aerogenes, as well as Gram-positive bacteria Staphylococcus aureus.


INDIAN DRUGS ◽  
2017 ◽  
Vol 54 (06) ◽  
pp. 20-29
Author(s):  
S Shukla ◽  
◽  
S. Gautam ◽  
S Chandra ◽  
A. Kumar

A string of novel coordination compounds of Cr(III) complexes have been derived and characterized from the macrocyclic ligands (L 1 -L 2 ) carried out by condensation reaction between ligands and the subsequent metal salt. The chemical composition of ligand was determined by analytical and spectral techniques i.e. elemental analysis, IR and Mass spectrocopy. Spectral techniques revealed tetradentate [N 4 ] the nature of ligand and its coordination mode to metal ion through nitrogen donor atoms. Metal complexes were characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, IR, electronic spectra, ePR studies. The geometry of these complexes was ascertained by molecular modelling study by using Gaussian 09 program. All metal complexes were found to exhibit octahedral geometry around the metal ion. The newly synthesized macrocyclic ligands and metal complexes were subjected for antimicrobial screening to determine the inhibition and control against tested microorganisms, bacteria ( S.lutea , S.aureus, S.albus and E.coli ) and fungi ( A.fulviceps, U . hordei, A. niger and P.catinus ) by using disc diffusion method and agar plate technique, respectively. The experimental results suggest that metal complexes exhibit enhanced inhibition zone than free macrocyclic ligand.


2019 ◽  
Vol 31 (4) ◽  
pp. 780-784
Author(s):  
P. Manimaran ◽  
S. Balasubramaniyan

The metal complexes of Fe(III) and Cu(II) were prepared by using 2,4-dinitrophenyl hydrazine (DNPH) and thiocyanate (SCN) with stirrer refluxed for about 6 h. The prepared Fe(III) and Cu(II) complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility and electronic spectrum, FT-IR spectral studies. The result suggested the octahedral geometry for Fe(III) and Cu(II) complexes. Powder X-ray diffraction indicate the crystalline nature of the metal complexes. The antimicrobial activities of the Fe(III) and Cu(II) complexes were tested with various micro organisms by disc diffusion method. The antimicrobial results indicate that the metal complexes are highly active with compared to the free ligand. The in vitro antioxidant activity of the free ligand and its metal complexes was assayed by radical scavenging activity (DPPH). The result proposed that Fe (III) and Cu(II) complexes exhibited strong antioxidant activity than that of the ligand.


2020 ◽  
Vol 32 (12) ◽  
pp. 3197-3202
Author(s):  
Rajeev Kumar ◽  
Sanjay Kumar ◽  
Madhu Bala

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.


2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Har Lal Singh ◽  
J. B. Singh

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.


2009 ◽  
Vol 74 (8-9) ◽  
pp. 927-938 ◽  
Author(s):  
Paulmony Tharmaraj ◽  
Deivasigamani Kodimunthiri ◽  
Clarence Sheela ◽  
Shanmuga Priya

A new series of Cu(II), Co(II) and Ni(II) complexes with the 1-(2- -hydroxyphenyl)-3-phenyl-2-propen-1-one, N2-[(3,5-dimethyl-1H-pyrazol-1- -yl)methyl]hydrazone ligand, C21H22N4O (LH), were synthesized by the reaction of 1-(2-hydroxyphenyl)-3-phenyl-2-propen-1-one, hydrazone with (3,5-dimethyl- 1H-pyrazol-1-yl)methanol and characterized. The nature of the bonding and geometry of the complexes were deduced from elemental analysis, IR, electronic and 1H-NMR spectroscopy, and magnetic susceptibility and conductivity measurements. The studies indicated square-planar, tetrahedral and octahedral geometry for the copper(II), cobalt(II) and nickel(II) complexes, respectively. The ESR spectra of the copper(II) complex in acetonitrile at 300 and 77 K were recorded and their salient features are reported. The electrochemical behavior of the copper (II) complex was studied by cyclic voltammetry. The antimicrobial activity of the ligand and its metal complexes were studied against the following strains of microorganism: Staphylococcus aureus, Salmonella enterica typhi, Escherichia coli and Bacillus subtilis by the well diffusion method. Metal complexes showed enhanced antimicrobial activity compared with that of the free ligand.


2015 ◽  
Vol 12 (2) ◽  
pp. 350-361 ◽  
Author(s):  
Baghdad Science Journal

A new series of metal ions complexes of VO(II), Cr(III), Mn(II), Zn(II), Cd(II) and Ce(III) have been synthesized from the Schiff bases (4-chlorobenzylidene)-urea amine (L1) and (4-bromobenzylidene)-urea amine (L2). Structural features were obtained from their elemental microanalyses, magnetic susceptibility, molar conductance, FT-IR, UV–Vis, LC-Mass and 1HNMR spectral studies. The UV–Vis, magnetic susceptibility and molar conductance data of the complexes suggest a tetrahedral geometry around the central metal ion except, VOII complexes that has square pyramidal geometry, but CrIII and CeIII octahedral geometry. The biological activity for the ligand (L1) and its Vanadium and Cadmium complexes were studied. Structural geometries of compounds also were suggested in gas phase by using theoretical treatments, using Hyper Chem-6 program for the molecular mechanics and semi-empirical calculations. The heat of formation (?Hf ?) and binding energy (?Eb) in the temperature of 298K for the free ligand (L1) and their metal complexes were calculated by PM3 and ZINDO/I methods. The electrostatic potential of the free ligands were calculated to investigate the reactive sites of the molecules.Bacteriological evaluation of considerable number of these compounds were maintained using organisms Escherichia coli and Staphylococcus aureus,and they were found to exhibit the high effect of activity. This may be attributed to the impact of both the Schiff bases and the metal present in these complexes.


2014 ◽  
Vol 10 (2) ◽  
pp. 2234-2245
Author(s):  
Safaa N. Abdou ◽  
Abeer A. Faheim ◽  
Abdel-Nasser M. A. Alaghaz

Complexes of cobalt(II), nickel(II), copper(II), zinc(II) and Hafnium(II) of general composition [M(L)2(Cl)2] have been synthesized [L = 4-(phenylphosphinylideneamino-N-thiazolylbenzenesulfonamide]. The elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, IR, UV, NMR, SEM, EDX, thermal and EPR spectral studies of the compounds led to the conclusion that the ligand acts as a bidentate manner. The molar conductance of the complexes in fresh solution of DMSO lies in the range of 7.46–9.13 Ω-1 cm2mol‒1 indicating their non-electrolytic behavior. On the basis of analytical and spectroscopic techniques, octahedral geometry of the complexes was proposed. The ligand acts as bidentate ligand, coordinated through sulfonamide oxygen and thiazole nitrogen atoms. The ligand field parameters were calculated for Co(II), Ni(II) and Cu(II) complexes and their values were found in the range reported for a octahedral structure. The catalytic activities of the divalent metal complexes have been studied in the oxidation of cyclohexane, using environmental friendly oxidant, hydrogen peroxide. Complex with rough surface has shown higher catalytic activity compared to the other complexes. The molecular parameters of the ligand and its Co(II) and Hf(II) complexes have been calculated. 


Sign in / Sign up

Export Citation Format

Share Document