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Synthesis, Spectral, Redox and Biological Screening Studies of Schiff Base Copper(II), Nickel(II), Cobalt(II), Oxovanadium(II) and Zinc(II) Complexes Derived from Curcumin and 4-Aminoantipyrine

Kulandaisamy A., Thomas M.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 3

469-480

EN

Neutral complexes of Cu(II), Ni(II), Co(II), VO(II) and Zn(II) have been synthesized from the new Schiff base de rived from curcumin and 4-aminoantipyrine. The structural features of the com plexes have been de ter mined from their microanalytical, magnetic susceptibility, molar conductance, IR, UV-Vis, 1H-NMR, mass and ESR spectral data. All the complexes exhibit square planar geometry while vanadyl complex exists in a square pyramidal geome try. Their magnetic susceptibility measurements and low conductance data provideevidence for the monomeric and non-electrolytic nature of the complexes respectively. Mass, 1H-NMR spectra of the Schiff base and its com plexes suggest that the general formula of the complexes is [ML2]. The redox behaviour of the Cu(II), Ni(II) and VO(II) complexes in MeCN at 300 K was studied by using cyclic voltammetry. The X-band ESR spectra of copper and vanadyl complexes in DMSO solution at 300 K and 77 K were recorded and their salient features were discussed. The antimicrobial activity of the ligand and its complexes against the bacteria Staphylococus aureus, Bacillus subtilis, Klebsiella pneumoniae, Salm nella typhi, Pseud monas aeruginosa and Shigella flexneri are also reported.

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Studies on DNA Cleavage and Antimicrobial Screening of Transition Metal(II) Complexes Derived from Tetradentate Schiff Base

Raman N., Dhaveethu Raja J., Sakthivel A.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 12

2059-2067

EN

A new series of transition metal complexes of Cu(II), Ni(II), Co(II), Mn(II), Zn(II), VO(IV), Hg(II) and Cd(II) have been synthesized from the Schiff base (H2L) derived from 4-aminoantipyrine, 3-hydroxy-4-nitrobenzaldehyde and 2-aminophenol. The structural features have been arrived from their elemental analyses, magnetic susceptibility, molar conductance, mass, IR, UV-Vis, 1H NMR and ESR spectral studies. The data show that the complexes have composition of ML type. The UV-Vis, magnetic susceptibility and ESR spectral data of the complexes suggest a square planar geometry around the central metal ion except VO(IV) complex which has square-pyramidal geometry. The redox behavior of copper and vanadyl complexes has been studied by cyclic voltammetry. The minimum inhibitory concentration (MIC) values of the in vestigated compounds indicate that the complexes have higher antimicrobial activity than the free ligand. The nuclease activity of the above metal complexes shows that only copper and nickel complexes cleave DNA through redox chemistry.

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Synthesis, structural Characterization, Cyclic Voltammetric and Antibecterial Studies of Tetraaza 13-Membered Macrocyclic Copper(II), NIckel(II), Cobalt(II) and Zinc(II) Complexes DErived from the Schiff Base 3-Salicylidene-2,4-di(imino-4'-antipyrinyl)pe

Raman N., Thangaraja C.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 7

1123-1134

EN

Atetraaza macrocyclic Schiff base (L), synthesized from the Schiff base 3-salicylidene- 2,4-di(imino-4_-antipyrinyl)pentane (3SDAP) and o-phenylenediamine, acts as a tetradentate ligand to form cationic solid complexes with Cu(II), Ni(II), Co(II) and Zn(II) metal salts in ethanol. All the synthesized complexes were characterized by microanalytical data, magnetic susceptibility measurements, IR, UV-Vis, 1H-NMR, 13C-NMR, ESR and mass spectral techniques. The IR and UV-Vis spectral data and magnetic susceptibility values of the complexes suggest that the [CuL]Cl2, [NiL]Cl2, [CoL]Cl2 and [ZnL]Cl2 complexes exhibit square-planar geometry. The electrolytic behaviour and monomeric nature of the chelates were confirmed from their molar conductance data and magnetic susceptibility values respectively. Cyclic voltammetric data of copper complex in DMSO reveal that the unusual oxidation states such as Cu(I) and Cu(0) are stabilized by the ligand system. The cyclic voltammogram of the nickel(II) complex was also recorded in DMSO solution and the salient features are reported. The X-band ESR spectra of the copper complex in DMSO solution at 300 K and 77 K were recorded and their spin Hamiltonian parameters were calculated. The in vitro biological screening effects of the investigated compounds were tested against some microorganisms. The metal complexes have higher activity than the free ligand and the standard.

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New Neutral Schiff Base and Its Metal Complexes Derived from Mannich Base, N-(1-Morpholinobenzyl)acetamideRaman, N.

Raman N., Ravichandran S.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 7

1107-1114

EN

New neutral Schiff base complexes of Cu(II), Co(II), Ni(II) and Zn(II) derived from 4-aminoantipyrine and N-(1-morpholinobenzyl)acetamide (Mannich base) have been synthesized. The structural features of the complexes have been confirmed by microanalytical data, IR, UV-Vis., NMR, EPR, and CV techniques. Electronic absorption spectra of the complexes indicate an octahedral geometry around the metal ion. Their magnetic susceptibility measurements and low conductance data provide evidence for the monomeric and neutral natures of the complexes respectively. The electrochemical behaviour, the anodic and cathodic potential and the number of electrons transferred were calculated using cyclic voltammogram. The X-band EPR spectrum of copper complex in DMSO at 300 K and 77 K was recorded and its salient features are reported. The antimicrobial activity of the ligand and its complexes has been extensively studied on microorganisms such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa and the fungi Aspergillus niger and Rhizoctonia bataicola by well-diffusion technique using DMF as solvent. It has been found that all the complexes have higher activity than the free ligand and the standard.

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Detector tube for the determination of chlorine in air

Pitschmann V., Kobliha Z., Halámek E., Tušarová I.

Chemia Analityczna

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2005

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Vol. 50, No. 4

729-734

EN

Brief information is given on a method of determination of chlorine in air using a detector tube. The detector tube contains silica gel with immobilized reagents 4-aminoantipyrine and N-(l-naphtyl)ethylenediamine dihydrochloride which are stabilized by sodium sulfite and triethylene glycol. Chlorine concentration in the range 15 to 150 mg m-3 is evaluated on the basis of the length of the blue-violet coloration of the indicator layer.

PL

Opracowano metodę oznaczania chloru w powietrzu przy zastosowaniu rurki wskaźnikowej. Rurka wskaźnikowa zawiera żel krzemionkowy z unieruchomionymi na nim odczynnikami: 4-aminoantypiryną. dichlorowodorkiem N-(I-naftylo)etylenodiaminy, stabilizowanymi siarczynem sodowym iglikolemtrietylenowym. Stężenie chloru w zakresie 15-150 mg m-3 ocenia się na podstawie długości niebiesko-fioletowego zabarwienia warstwy wskaźnika.