scholarly journals Synthesis, spectral characterization, redox and antimicrobial activity of Schiff base transition metal(II) complexes derived from 4-aminoantipyrine and 3-salicylideneacetylacetone

2005 ◽  
Vol 3 (3) ◽  
pp. 537-555 ◽  
Author(s):  
Natarajan Raman ◽  
Chinnathangavel Thangaraja ◽  
Samuelraj Johnsonraja
Keyword(s):  
Antimicrobial Activity ◽  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Transition Metal ◽  
Metal Ion ◽  
Free Ligand ◽  
Transition Metal Ions ◽  
Planar Geometry ◽  
Cyclic Voltammogram ◽  
Central Metal

AbstractA novel tetradentate N2O2 type Schiff base, synthesized from 1-phenyl-2,3-dimethyl-4-aminopyrazol-5-one(4-aminoantipyrine) and 3-salicylidene-acetylacetone, forms stable complexes with transition metal ions such as CuII, NiII, CoII and ZnII in ethanol. Microanalytical data, magnetic susceptibility, IR, UV-Vis.,1H-NMR, ESR and Mass spectral techniques were used to confirm the structures. Electronic absorption spectra of the complexes suggest a square-planar geometry around the central metal ion. These complexes show higher conductance values, supporting their electrolytic nature. The monomeric nature of the complexes was confirmed from their magnetic susceptibility values. Cyclic voltammogram of the copper(II) and nickel(II) complexes in DMSO solution at 300 K were recorded and the results are discussed. The X-band ESR spectra of the copper complex were recorded and the molecular orbital coefficient values were calculated from the spectra. The in vitro antimicrobial activities of the investigated compounds were tested against bacteria such as Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis and Escherichia coli and fungi like Aspergillus niger and Rhizoctonia bataicola. Most of the metal chelates show higher antimicrobial activity for the above microorganisms than that of the free ligand.

scholarly journals Designing, synthesis and spectral characterization of Schiff base transition metal complexes: DNA cleavage and antimicrobial activity studies

2008 ◽  
Vol 73 (11) ◽  
pp. 1063-1071 ◽  
Author(s):  
N. Raman ◽  
Syed Ali ◽  
Dhaveethu Raja
Keyword(s):  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Transition Metal ◽  
Metal Complexes ◽  
Spectral Data ◽  
Transition Metal Complexes ◽  
Metal Ion ◽  
Spectral Studies ◽  
Central Metal ◽  
Elemental Analyses

A new series of transition metal complexes of Cu(II), Ni(II), Co(II) and Zn(II) have been designed and synthesized using a Schiff base (L) derived from 4-aminoantipyrine, benzaldehyde and o-phenylenediamine. The structural features were derived from their elemental analyses, magnetic susceptibility and molar conductivity, as well as from mass, IR, UV-Vis, 1H-NMR and ESR spectral studies. The FAB mass spectral data and elemental analyses showed that the complexes had a composition of the ML type. The UV-Vis and ESR spectral data of the complexes suggested a square-planar geometry around the central metal ion. The magnetic susceptibility values of the complexes indicated that they were monomeric in nature. Antimicrobial screening tests were also performed against four bacteria, viz. Salmonella typhi, Staphylococcus aureus, Escherichia coli, and Bacillus subtilis and three fungi, viz. Aspergillus niger, Aspergillus flavus and Rhizoctonia bataicola. These data gave good results in the presence of metal ion in the ligand system. The nuclease activity of the above metal complexes shows that only the copper complex cleaves CT DNA in the presence of an oxidant.

Synthesis, Characterization and in vitro Biological Evaluation of a New Schiff Base Derived from Drug and its Complexes with Transition Metal Ions

2018 ◽  
Vol 69 (7) ◽  
pp. 1678-1681
Author(s):  
Amina Mumtaz ◽  
Tariq Mahmud ◽  
M. R. J. Elsegood ◽  
G. W. Weaver
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Ions ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Free Ligand ◽  
Transition Metal Ions ◽  
Biological Evaluation ◽  
Pyridoxal Hydrochloride

New series of copper (II), cobalt (II), zinc (II), nickel (II), manganese (II), iron (II) complexes of a novel Schiff base were prepared by the condensation of sulphadizine and pyridoxal hydrochloride. The ligand and metal complexes were characterized by utilizing different instrumental procedures like microanalysis, thermogravimetric examination and spectroscopy. The integrated ligand and transition metal complexes were screened against various bacteria and fungus. The studies demonstrated the enhanced activity of metal complexes against reported microbes when compared with free ligand.

scholarly journals Preparation, spectral characterization, structural study, and evaluation of antibacterial activity of Schiff base complexes for VOII, CrIII, MnII, ZnII,CdII and CeIII

2015 ◽  
Vol 12 (2) ◽  
pp. 350-361 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Magnetic Susceptibility ◽  
Schiff Bases ◽  
Metal Ion ◽  
Free Ligand ◽  
Molar Conductance ◽  
Schiff Base Complexes ◽  
Spectral Studies ◽  
Central Metal ◽  
Tetrahedral Geometry ◽  
The Impact

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.

scholarly journals Synthesis, Characterization, Biological Activity and DNA Binding Studies of Metal Complexes with 4-Aminoantipyrine Schiff Base Ligand

2012 ◽  
Vol 9 (1) ◽  
pp. 389-400 ◽  
Author(s):  
B. Anupama ◽  
M. Padmaja ◽  
C. Gyana Kumari
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Schiff Base Ligand ◽  
Metal Ion ◽  
Spectral Studies ◽  
Significant Activity ◽  
Central Metal ◽  
Binding Studies

A new series of transition metal complexes of Cu(II),Ni(II),Co(II), Zn(II) and VO(IV) have been synthesized from the Schiff base ligand (L) derived from 4-amino antipyrine and 5- bromo salicylaldehyde. The structural features of Schiff base and metal complexes were determined from their elemental analyses, thermogravimetric studies, magneticsusceptibility, molar conductivity, ESI-Mass, IR, UV-VIS,1H NMR and ESR spectral studies. The data show that the complexes have composition of ML2type. The UV-VIS, magnetic susceptibility and ESR spectral data suggest an octahedral geometry around the central metal ion. Biological screening of the complexes reveals that the Schiff base transition metal complexes show significant activity against microorganisms. Binding of Co(II) complex with calf thymus DNA (CT DNA) was studied by spectral methods.

scholarly journals Synthesis, Characterization and Magnetic Susceptibility of Novel Transition Metal Ion Complexes with (E)-2-((7H-Purin-6-ylimino)methyl)phenol and Its Antibacterial Efficiency

2021 ◽  
Vol 7 (4) ◽  
pp. 748-750
Author(s):  
S. Tihile Mangesh ◽  
N. Chaudhari Gajanan
Keyword(s):  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Transition Metal ◽  
Metal Ion ◽  
Spectroscopic Techniques ◽  
The Novel ◽  
Metal Ion Complexes ◽  
Transition Metal Ion ◽  
Ft Ir

The novel transition metal ion complexes were synthesized by refluxing the ethanolic solutions of metal acetates with Schiff base in 1:2 ratios. The structure and characterization of synthesized complexes of Mn (II), Co (II), Ni (II), Cu (II) and Zn (II) with Schiff base (E)-2-((7H-purin-6-ylimino)methyl)phenol were elucidated by using 1H NMR, FT-IR and UV-Visible spectroscopic techniques. The synthesized compounds were also been screened against gram positive and gram-negative bacteria. The novel compounds were further carried out for the study of magnetic susceptibility.

scholarly journals Synthesis, characterization and antimicrobial activity of Mn(II), Co(II) and Ni(II) complexes with schiff base derived from 4-chloroaniline and salicylaldehyde

2018 ◽  
Vol 11 (1) ◽  
pp. 61-66
Author(s):  
A.K. Ibrahim ◽  
B.A. Yusuf ◽  
B.U. Sambo
Keyword(s):  
Antimicrobial Activity ◽  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Metal Complexes ◽  
Infrared Spectra ◽  
Free Ligand ◽  
Conductivity Measurement ◽  
Moderate Activity ◽  
Ligand Ratio ◽  
Metal Ligand

Transition Metal Complexes of Mn(II),Co(II) and Ni(II) with Schiff base derived from 4- chloroaniline and Salicylaldehyde were synthesized and characterized by conductivity measurement, magnetic susceptibility, infrared spectra, metal-ligand ratio determination and solubility test. The Schiff base and its metal complexes were tested for antibacterial activity against Staphylococcus aureus and Escherichia coli and fungal activity against Aspergillus flavus and Mucor species. The low molar conductance values range (16-28.1Ohm- cm2 mol-1) indicated that all the complexes are non electrolytes. The magnetic susceptibility revealed that all the complexes are paramagnetic in nature. The metal-ligand ratio was found to be 1:2 in all the complexes. The infrared spectra suggested that the Schiff base behaves as a bidentate ligand. The antimicrobial studies revealed moderate activity against the tested organism when compared with the standards (Ciprofloxacin and Ketoconazole), and this activity increases by increasing concentration. And also the Metal Complexes showed higher activity than free Ligand due to chelation.Keywords: Salicyldehyde, 4-chloroaniline, Mn(II), Co(II), Zn(II) complexes, antimicrobial activity

scholarly journals Synthesis, characterization and thermal study of some transition metal complexes of an asymmetrical tetradentate Schiff base ligand

2010 ◽  
Vol 75 (3) ◽  
pp. 349-359 ◽  
Author(s):  
Achut Munde ◽  
Amarnath Jagdale ◽  
Sarika Jadhav ◽  
Trimbak Chondhekar
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Schiff Base Ligand ◽  
Metal Ion ◽  
Trichoderma Viride ◽  
Planar Geometry ◽  
Central Metal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Tetradentate Schiff Base

Complexes of Cu(II), Ni(II), Co(II), Mn(II) and Fe(II) 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(II) 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(II) 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.

scholarly journals Synthesis and Characterization with Antimicrobial Activity Studies on some Transition Metal Complexes of N, O Donor Novel Schiff Base Ligand

2017 ◽  
Vol 9 (2) ◽  
pp. 209-218 ◽  
Author(s):  
M. S. Hossain ◽  
C. M. Zakaria ◽  
M. K. Zahan
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Metal Complexes ◽  
Schiff Base Ligand ◽  
Transition Metal Ions ◽  
Tridentate Ligand ◽  
Central Metal Atom ◽  
Complexation Reaction ◽  
Central Metal ◽  
Physical Measurements

Metal complexes of Mn(II), Fe(II), Co(II) and Cd(II) ions with Schiff base ligand 4-{(pyridin-2-ylimino)methyl}phenol derived from condensation of 2-amino pyridine with 4-hydroxybenzaldehyde was prepared. The ligand and complexes were isolated from the reaction in the solid form  and characterized by conductivity, magnetic moment, TLC, IR, UV-Visible, thermal analysis and some physical measurements. During complexation reaction with transition metal ions Schiff base act as a deprotonated tridentate ligand and IR spectra showed that N and O atoms are coordinated to the central metal atom. The observed values confirmed that the complexes have octahedral geometry. The Schiff base and its metal complexes have been found to have moderate to strong antibacterial activity.

scholarly journals Synthesis, spectroscopic and antimicrobial studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes derived from benzoic acid bidentate Schiff base ligand

2021 ◽  
Vol 25 (9) ◽  
pp. 1599-1603
Author(s):  
I. ADO ◽  
J. NA’ALIYA ◽  
S. SANI ◽  
M.M. HALEELU
Keyword(s):  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Elemental Analysis ◽  
Schiff Base Ligand ◽  
Magnetic Moment ◽  
Metal Ion ◽  
Molar Conductance ◽  
Molar Ratio ◽  
Planar Geometry ◽  
Azomethine Group

The Schiff base was synthesized by condensation of 2-hydroxy-1-naphthaldehyde with 3- aminobenzoic acid in 1:1 molar ratio. The Schiff base ligand formed complexes with Co (II), Ni (II), Cu (II) and Zn (II) acetate via mechanochemical synthesis. The synthesized compounds were characterized by solubility test, thermal analysis, FT-IR, powder x-ray diffraction, molar conductance measurement, magnetic susceptibility and elemental analysis. The Schiff base has a melting point of 190 oC. The decomposition temperature of complexes was found to be in the range 289 – 302 oC. The Schiff base and its metal (II) complexes were soluble in DMF, DMSO and sparingly soluble in acetonitrile, chloroform, diethyl ether and insoluble in n-hexane which indicate the polar nature of the synthesized compounds. The IR spectral analysis of the free Schiff base shows a band at 1622 cm-1, assigned to v(C=N) stretching vibrations. This band was shifted in the spectra of complexes (1607 – 1633 cm-1), indicating coordination of the Schiff base to the metal ion through the azomethine group. The molar conductance of complexes determined are in the range 9.51 – 14.87 Ohm-1cm2mol-1 which indicate the non-electrolytic nature in DMF. Magnetic susceptibility measurements of Co (II), Ni (II) and Cu (II) complexes exhibit a magnetic moment in the range 1.25 – 3.08 BM. The values correspond to square-planar geometry. The magnetic moment value of Zn (II) complex indicates a diamagnetic behaviour. The elemental analysis of the complexes for C, H and N determined showed that the observed and the calculated percentages of the elements are in good agreement.

Effect of solvent binding on UV-vis spectra and redox potentials of octaethylporphyrins containing first-row transition metal ions

2009 ◽  
Vol 13 (12) ◽  
pp. 1233-1242 ◽  
Author(s):  
Weihua Zhu ◽  
Xiaofeng Zhao ◽  
Zhongping Ou ◽  
Fan Zhou ◽  
Xiaohong Wang ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Metal Ion ◽  
Binding Constants ◽  
Transition Metal Ions ◽  
Donor Number ◽  
Central Metal ◽  
Redox Potentials ◽  
Visible Spectra ◽  
Uv Visible

The UV-visible spectra and oxidation/reduction potentials for six octaethylporphyrins with first-row transition metal ions were measured in four non-aqueous solvents and then analyzed as a function of the Gutmann solvent parameters, donor number (DN) or acceptor number (AN). The utilized solvents were dichloromethane ( CH2Cl2 ), N, N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and pyridine (py). The investigated porphyrins were (OEP)M, where OEP = the dianion of octaethylporphyrin and M = CoII, NiII, CuII, ZnII, FeIIICl or MnIIICl . UV-visible spectra upon solvent (S) binding to give (OEP)M(S) or [ (OEP)M(S)2]+Cl- were monitored during a titration of the porphyrin in CH2Cl2 and formation constants ( logβ n, n = 1 or 2) for the ligand addition reactions were determined using standard equations. Five-coordinate (OEP)CoII(S) and (OEP)ZnII(S) are generated in CH2Cl2 solutions containing DMF, DMSO or py while six-coordinate [ (OEP)Mn(S)2]+Cl and [ (OEP)Fe(S)2]+Cl- are formed under the same solution conditions. The magnitudes of the solvent binding constants are discussed in terms of both the solvent donor/acceptor properties and the electronegativity (EN) or stability index (SI) of the porphyrin central metal ion. A comparison between solvent binding constants measured in this study for (OEP)M and literature data for (TPP)M with the same central metal ions is presented.

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