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1.
《中国化学会会志》2017,64(12):1524-1531
New complexes of nickel(II) and palladium(II) were synthesized using the ferrocenyl imine ligand, which was formed by the condensation of 2‐aminothiophenol and acetylferrocene. This bidentate Schiff base ligand was coordinated to the metal ions through the NS donor atoms. Monomeric complexes of nickel(II) and palladium(II) were synthesized by the reactions of the Schiff base ligand with nickel(II) and palladium(II) chloride in a 2:1 M ratio. In these complexes, the thiol group was deprotonated and coordinated to the metals. The molar conductivity values of the complexes in DMSO showed the presence of non‐electrolyte species. The fluorescence characteristics of the Schiff base ligand and its complexes were studied in DMSO. The synthesized complexes were characterized by FT‐IR, 1H NMR, UV–vis spectroscopy, elemental analysis, and conductometry. Furthermore, the binding interactions of the complexes with DNA were investigated by electronic absorption spectroscopy, and the intrinsic binding constant (K b) was calculated. Moreover, viscosity and melting temperature (T m) were investigated in order to further explore the nature of interactions between the complexes and DNA.  相似文献   

2.
A novel Schiff base ligand (H2L) was prepared through condensation of 2,6‐diaminopyridine and o‐benzoylbenzoic acid in a 1:2 ratio. This Schiff base ligand was characterized using elemental and spectroscopic analyses. A new series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) metal complexes of H2L were prepared and characterized using elemental analysis, spectroscopy (1H NMR, mass, UV–visible, Fourier transform infrared, electron spin resonance), magnetic susceptibility, molar conductivity, X‐ray powder diffraction and thermal analysis. The complexes are found to have trigonal bipyramidal geometry except Cr(III), Mn(II) and Fe(III) complexes which have octahedral geometry based on magnetic moment and solid reflectance measurements. The infrared spectral studies reveal that H2L behaves as a neutral bidentate ligand and coordinates to the metal ions via the two azomethine nitrogens. 1H NMR spectra confirm the non‐involvement of the carboxylic COOH proton in complex formation. The presence of water molecules in all reported complexes is supported by thermogravimetric studies. Kinetic and thermodynamic parameters were determined using Coats–Redfern and Horowitz–Metzger equations. The synthesized ligand and its complexes were screened for antimicrobial activities against two Gram‐positive bacteria (Bacillus subtilis and Staphylococcus aureus), two Gram‐negative bacteria (Escherichia coli and Neisseria gonorrhoeae) and one fungus (Candida albicans). Anticancer activities of the ligand and its metal complexes against human breast cancer cell line (MCF7) were investigated. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

3.
New hexa‐coordinated binuclear Ru(III) Schiff base complexes of the type {[(B)2X2Ru]2L} (where B = PPh3 or AsPh3; X = Cl or Br; L = binucleating N2O2 Schiff bases) were synthesized and characterized by elemental analysis, magnetic susceptibility measurement, FT‐IR, UV–vis, 13C{1H}‐NMR, ESR at 300 and 77 K, cyclic voltammetric technique, powder X‐ray diffraction pattern and SEM. The new complexes were used as catalysts in phenyl–phenyl coupling reaction and the oxidation of alcohols to their corresponding carbonyl compounds using molecular oxygen atmosphere at room temperature. Further, the new Schiff base ligands and their Ru(III) complexes were also screened for their antibacterial activity against K. pneumoniae, Shigella sp., M. luteus, E. coli and S. typhi. From this study, it was found that the activity of the ruthenium(III) Schiff base complexes almost reaches the effectiveness of the conventional bacteriocide standards. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
A bidentate/tridentate 5-bromosalycilaldehyde isonicotinoylhydrazone Schiff base was synthesized by condensing 5-bromosalycilaldehyde with isonicotinoylhydrazine. Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) complexes of this chelating ligand were synthesized using nitrates of these metals. The ligand and the complexes were characterized by elemental analysis, UV–Vis, IR and EPR spectroscopy, conductance and magnetic susceptibility measurements, fluorescence, cyclic voltammetry and thermogravimetric analysis. The ligand and Zn(II) complex exhibits solid-state photoluminescence at room temperature.  相似文献   

5.
A series of four novel metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) were synthesized from Schiff base derived from amoxicillin (AMX) and picolinaldehyde (PC2). The ligand and metal complexes were fully characterized by physical and spectral techniques such as elemental microanalysis, conductivity, FT-IR, 1H & 13C NMR, UV–vis, mass spectra, EPR, magnetic moment measurement, TGA/DTA, PXRD and antibacterial activity study. The spectroscopic study revealed 1:2 metal ligand ratio and coordination sites in the ligand for metal ions were evaluated by analysis of the spectral results. The surface morphology of the complexes was evaluated by SEM analysis. Molar conductivity implies non-electrolytic nature of the complexes. UV–vis. spectral study nicely supports octahedral geometry for Co(II) and Zn(II) complexes and tetrahedral geometry for Cu(II) complex. The kinetic parameters were extracted from Coats-Redfern equation. The PXRD study revealed nano-crystalline nature of Co(II), Ni(II) & Cu(II) complexes and amorphous nature of Zn(II) complex. The proposed geometry of the complexes was optimized by MM2 calculation supported in Cs-ChemOffice Ultra-11 program. The ligand and metal complexes were screened for antibacterial potency against four human pathogenic clinical strains of bacteria and the data revealed their promising antibacterial activity.  相似文献   

6.
A novel Schiff base compound was synthesized, and its complexation properties with Fe(III) and Cr(III) were investigated. Tripodal ligand was synthesized by the reaction of s‐triazine and 4‐hydroxybenzaldehyde. Then a Schiff base involving 8‐hydroxyquinoline was synthesized by the reaction of 5‐aminomethyl‐8‐hydroxyquinoline ( QN ) and 2,4,6‐tris(p‐formylphenoxy)‐1,3,5‐triazine ( TRIPOD ) in methanol/chloroform media. The obtained Schiff base ( QN-TRIPOD ) was then reacted with four trinuclear Fe(III) and Cr(III) complexes including tetradentate Schiff bases N ,N ′‐bis(salicylidene)ethylenediamine (salenH2)/bis(salicylidene)‐o‐phenylenediamine (SalophenH2). The synthesized ligand and complexes were characterized by means of elemental analysis carrying out 1H NMR, FTIR spectroscopy, thermal analyses, and magnetic susceptibility measurements. Finally, metal ratios of the prepared complexes were determined by using atomic adsorption spectrometry.  相似文献   

7.
In search of effective bioactive compounds, we have synthesized the new Co(II), Ni(II), and Cu(II) complexes of the Schiff base derived from 8-formyl-7-hydroxy-4-methylcoumarin and 2-hydrazino benzothiazole and characterized by analytical, spectroscopic (IR, NMR, UV–vis, Mass), magnetic, powder X-ray diffraction data (PXRD) and TGA studies. Elemental analysis suggests the stoichiometry of the synthesized complexes and the solution electronic spectral study revealed the octahedral geometry of the compounds. Thermal analysis shows the presence of water molecule outside the coordination sphere and powder-XRD patterns have been studied to test the degree of crystallinity of the complexes and unit cell calculations were made. All the synthesized compounds were tested against human ovarian cancer cell line (PA-1). The synthesized metal complexes exhibited enhanced activity against the tested bacterial (Staphylococcus aureus and Escherichia Coli) and fungal strains (Candida albicans and Aspergillus fumigatus) as compared to free ligand (LH). The results of the DNA-cleavage activity suggest that the ligand and its metal complexes can cleave CT-DNA at different degrees. Further, anti-tuberculosis activity was done using microplate almar blue assay. Among all these synthesized compounds, the Cu(II) complex exhibits good cleaving ability compared to other newly synthesized metal complexes.  相似文献   

8.
The Schiff base ligand, N,N'-bis-(2-thiophenecarboxaldimine)-3,3'-diaminobenzidine (L) obtained from condensation of 2-thiophenecarboxaldehyde and 3,3'-diaminobenzidine, was used to synthesize the complexes of type, [M2L2]Cl4 [M=Co(II), Ni(II), Cu(II), Cd(II) and Hg(II)]. The newly synthesized ligand (L) was characterized on the basis of the results of elemental analysis, FT-IR, 1H NMR, 13C NMR, mass spectroscopic studies and single crystal X-ray crystallography. The characteristic resonance signals in 1H NMR and 13C NMR spectra indicated the presence of azomethine group as a result of condensation reaction. The stoichiometry, bonding and stereochemistries of complexes were ascertained on the basis of results of elemental analysis, magnetic susceptibility measurements, molar conductance and spectroscopic studies viz., FT-IR, 1H and 13C NMR, UV-vis and EPR. EPR, UV-vis and magnetic moment data revealed an octahedral geometry for complexes with distortion in Cu(II) complex and conductivity data show 1:2 electrolytic nature of complexes. Absoption and fluorescence spectroscopic studies supported that Schiff base ligand L and its Co(II), Ni(II) and Cu(II) complexes exhibited significant binding to calf thymus DNA. The complexes exhibited higher affinity to calf thymus DNA than the free Schiff base ligand L.  相似文献   

9.
Ni(II), Cu(II), Co(II), and Pd(II) complexes were synthesized with a Schiff base containing thioether with ONS donors chelating to the metal center. The ligand and complexes were characterized by elemental analysis, FT-IR, 1H-NMR, UV–visible spectroscopy and magnetic studies. The crystal structures of the ligand and its Ni(II) and Pd(II) complexes were determined by single-crystal X-ray diffraction analysis. Structures revealed that the ligand chelated with Ni(II) and Pd(II) center in slightly distorted octahedral and slightly distorted square planar fashion, respectively. DFT studies of the Pd(II) complex revealed that the calculated structural parameters are very close with the experimentally observed data. The Cu(II) complex shows very good catalytic activity toward the conversion of alcohol to aldehyde under aerobic oxidation with ammonium persulfate.  相似文献   

10.
Four new mononuclear metal complexes with a mononucleating Schiff base ligand containing two thiadiazoles units have been synthesized. The ligand and metal complexes were characterized by elemental analyses, IR, 1H, and 13C NMR, UV–vis, ESR, electrospray ionization mass spectra, and magnetic susceptibility measurements. Electronic spectra, magnetic susceptibility measurement, and molecular modeling studies support octahedral geometry around the Ni(II), Cu(II), and Zn(II) ions. The magnetic properties were investigated, and ferromagnetic coupling is observed in Cu(II) and Ni(II) complexes. In addition, total energy and heat of formation calculated for conformers of the Schiff base ligand by the semiempirical AM1 calculations have shown that E,Z‐isomer of the ligand is more stable (about 5.3 kcal/mol) than E,E‐ and Z,Z‐isomers. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:700–712, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20496  相似文献   

11.
Reactions of 1,2-di(o-aminophenylthio)ethane with 3-ethoxy-2-hydroxybenzaldehyde yield the new hexadentate N2S2O2 donor thioether Schiff base 1,2-bis(2-((2-(thio)phenylimino)methyl)-6-ethoxyphenol)ethane (H2L). Ni(II), Zn(II), Cd(II), and Hg(II) complexes of this ligand were prepared. Of these complexes, [NiL]·2H2O has been structurally characterized by X-ray crystallography. The coordination geometry around Ni(II) was described as octahedral. Zn(II), Cd(II), and Hg(II) complexes and the Schiff base ligand have been characterized by CHN analyses, molar conductivity, UV–vis, FT-IR, 1H, and 13C NMR spectroscopy.  相似文献   

12.
A new Schiff base N-[(E)-(2-hydroxyphenyl)methylidene]-N’-[(Z)-(2-hydroxyphenyl)methylidene]ethanebis(thioamide) (LC) containing sulfur, nitrogen, and oxygen atoms has been synthesized by condensation of ethanebis(thioamide) with 2-hydroxybenzaldehyde. Metal complexes were synthesized by reaction of the new ligand with copper(II) and cobalt(II) as nitrate salts and with rhodium(III) as chloride salt, using hot absolute ethanol as solvent. All the new compounds were characterized by use of different physicochemical techniques including UV–visible spectroscopy, magnetic susceptibility, IR spectroscopy, molar conductance, and determination of metal content. It is proposed the paramagnetic copper and cobalt complexes adopt octahedral geometry whereas the diamagnetic rhodium complex has octahedral geometry.  相似文献   

13.
In the present study, we discussed to synthesis of a new Schiff base with nitro groups and its complexation properties with Fe/Cr(III) salen/salophen capped complexes. For this, 1,3,5-tris (formylphenoxymethyl)benzene (1, TRIPOD) involving aldehyde groups was converted to the Schiff base derivative (2, TNPIM-TRIPOD) using 4-nitroaniline. The synthesized compound 2 were reacted with four new trinuclear Fe(III) and Cr(III) complexes involving tetradenta Schiff bases N,N-bis(salicylidene)ethylenediamine-(salenH2) or bis(salicylidene)-o-phenylenediamine-(salophenH2). Characterization of all compounds was made with elemental analysis, infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), nuclear magnetic resonance (1H-NMR), and magnetic susceptibility measurement. The complexes can also be characterized as low-spin distorted octahedral Fe(III) and Cr(III) bridged by nitro groups.  相似文献   

14.
In the search of effective bioactive compounds, Co(II) ( C1 ) and Cd(II) ( C2 ) complexes of the type [M(FMAPIMP)(H2O)Cl].nH2O (where M = Co(II); n = 2, Cd(II); n = 3, and FMAPIMP = ligand[2-((E)-((2-(((E)-furan-2-ylmethylene)amino)phenyl)imino)methyl)phenol]) were synthesized and characterized using elemental analysis, UV–Vis., cyclic voltammetry, Fourier-transform infrared (FT-IR), nuclear magnetic resonance, and mass spectral studies. The thermal stability of nano-sized Co(II) and Cd(II) complexes was studied using thermogravimetric analysis (TGA). Cobalt and cadmium oxides were synthesized using cobalt and cadmium nanoparticle (NP) structure Schiff base complexes as the raw material after calcination for 5 h at 600 °C. According to the results, Co(II) and Cd(II) complexes with mole ratio 1:1 of metal: H-FMAPIMP which octahedral are the most probable geometry for it. On the contrary, synthesized C1 and C2 NPs were used as suitable precursors for the preparation of CoO and CdO NPs. The obtained NPs were characterized using FT-IR, UV–Vis., TGA, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy techniques. PXRD analysis revealed that the obtained oxides were crystalline and corresponded to CoO and CdO phases. Crystal size, shape, and morphology were determined using SEM and TEM. H-FMAPIMP and its two complexes ( C1 and C2 ) were tested against human ovarian cancer cell line (PA-1). The synthesized Co(II) and Cd(II) complexes exhibited enhanced activity against the tested bacterial (Staphylococcus aureus and Escherichia Coli) and fungal strains (Candida albicans and Aspergillus fumigatus) as compared to H-FMAPIMP. The results of the DNA-cleavage activity indicated that the ligand and its two complexes can cleave calf thymus-DNA at different degrees. Further, antituberculosis activity was performed using microplate alamarBlue assay. Among all these synthesized compounds, C1 exhibited good cleaving ability compared to the newly synthesized C2 . Finally, the geometry of H-FMAPIMP and its Co(II) and Cd(II) complexes was optimized using molecular modeling.  相似文献   

15.
New Schiff base complexes of zinc(II), copper(II), nickel(II), and vanadium(IV) were synthesized using the Schiff base ligand formed by the condensation of 2-aminoethanethiol and 2-hydroxy-1-naphthaldehyde. The tetradentate Schiff base ligand N,N´-(3,4-dithiahexane-1,6-diyl)bis(2-hydroxy-1-naphthaleneimine), containing a disulfide bond, was coordinated to the metal(II) ions through the two azomethine nitrogen atoms and two deprotonated phenolic oxygens of two different ligands which was connected to each other by sulfur-sulfur bond. The molar conductivity values of complexes in DMSO solvent implied the presence of nonelectrolyte species. The fluorescence properties of the Schiff base ligand and its complexes were studied in dimethylsulfoxide. The Schiff base ligand and its complexes were characterized by FT-IR, 1H NMR, UV/Vis spectroscopies, elemental analysis, and conductometry. The crystal structure of tetradentate Schiff base ligand was characterized by single crystal X-ray diffraction. The Schiff base ligand was contained disulfide bond. Furthermore, the binding interaction of these complexes with calf thymus DNA (CT-DNA) was investigated by different methods.  相似文献   

16.
An interesting series of binuclear ruthenium(III) Schiff base complexes bearing bis-salophen/bis-naphophen units of the general composition [(EPh(3))(X)Ru-L-Ru(X)(EPh(3))] (where E=P or As; X=Cl or Br; L=binucleating dianionic tetradentate ligands) have been synthesized and characterized by analytical (elemental analysis, magnetic susceptibility measurements), spectral (FT-IR, UV-vis and EPR) and electrochemical methods. These ruthenium(III) complexes have two N(2)O(2) metal binding sites, which are linked to each other with a biphenyl bridge and acts as potential catalyst for oxidation of wide range of primary and secondary alcohols to corresponding aldehydes or ketones with moderate to high conversion in the presence of N-methylmorpholine-N-oxide (NMO). The formation of high-valent Ru(V)=O species as a catalytic active intermediate is proposed for the catalytic processes.  相似文献   

17.
Abstract

New metal complexes of Co(II), Cu(II), Ni(II), Zn(II), Mn(II), Fe(III), Ru(III), UO2(II), and VO(II) with the Schiff base, 2-(5-((2-chlorophenyl)diazenyl)-2-hydroxy- benzylidene) hydrazine-carbothioamide (H2L) have been prepared and characterized by elemental and thermal analyses, FT-IR, UV–Vis, mass spectra, 1H-NMR, and ESR as well as conductivity and magnetic moments measurements. The IR spectra showed that the ligand acts as neutral tridentate, neutral bidentate or monobasic tridentate ligand. The geometries of metal complexes were either octahedral or square pyramidal. The ESR spectra of the solid copper(II) complexes indicated an axial symmetry type of a d(x2-y2) ground state with considerably ionic or covalent environment. The effect of the presence of an azo group on the biological activity of the ligand was investigated. The ligand and its complexes are biologically inactive due to the presence of azo group.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the related elements to view the free supplemental file.  相似文献   

18.
A series of air stable low spin Ru(III) complexes, [RuX2(EPh3)(L)] (where X = Cl or Br; E = P or As; L = monobasic tridentate Schiff-base ligand), have been synthesized by reacting [RuCl3(PPh3)3], [RuCl3(AsPh3)3], and [RuBr3(PPh3)3] with the Schiff base in 1 : 1 molar ratio in benzene. These complexes have been characterized by elemental analysis, FT-IR, UV-Vis, and EPR spectroscopy together with magnetic susceptibility. The redox behaviors of the complexes have been investigated by cyclic voltammetric technique. Catalytic efficiency of the ruthenium complexes was determined for aryl–aryl coupling and the oxidation of primary and secondary alcohols into their corresponding aldehydes and ketones in the presence of molecular oxygen as co-oxidant. All complexes were screened for antibacterial activity.  相似文献   

19.
《中国化学会会志》2017,64(3):261-281
A new Schiff base was prepared from the reaction of 4,4′‐methylenedianiline with 2‐benzoylpyridine in 1:2 molar ratio, as well as its different metal chelates. The structures of the ligand and its metal complexes were studied by elemental analyses, spectroscopic methods (infrared [IR ], ultraviolet–visible [UV –vis], 1H nuclear magnetic resonance [NMR ], electron spin resonance [ESR ]), magnetic moment measurements, and thermal studies. The ligand acts as tetradentate moiety in all complexes. Octahedral geometry was suggested for Mn(II ), Cu(II ), Cr(III ), and Zn(II ) chloride complexes and pentacoordinated structure and square planar geometry for Co(II ), Ni(II ), Cu(NO3 )2, CuBr2 , and Pd(II ) complexes. ESR spectra of copper(II ) complexes ( 4 )–( 6 ) at room temperature display rhombic symmetry for complex ( 4 ) and axial type symmetry for complexes ( 5 ) and ( 6 ), indicating ground state for Cu(II ) complexes. The derivative thermogravimetric (DTG ) curves of the ligand and its metal complexes were analyzed by using the rate equation to calculate the thermodynamic and kinetic parameters, which indicated strong binding of the ligand with the metal ion in some complexes. Also, some of these compounds were screened to establish their potential as anticancer agents against the human hepatic cell line Hep‐G2 . The obtained IC50 value of the copper(II ) bromide complex (4.34 µg/mL ) is the highest among the compounds studied.  相似文献   

20.
N-(thiophen-2-ylmethylene)benzo[d]thiazol-2-amine Schiff base (L) derived from 2-aminobenzothiazole and 2-thiophenecarboxaldehyde was synthesized and characterized using elemental analysis, IR, mass spectra, (1)H NMR and UV-vis spectra. Its complexes with Cu(II), Fe(III), Ni(II) and Zn(II) were prepared and isolated as solid products and characterized by elemental and thermal analyses, spectral techniques as well as magnetic susceptibility. The IR spectra showed that the Schiff base under investigation behaves as bidentate ligand. The UV-vis spectra and magnetic moment data suggested octahedral geometry around Cu(II) and Fe(III) and tetrahedral geometry around Ni(II) and Zn(II). In view of the biological activity of the Schiff base and its complexes, it has been observed that the antimicrobial activity of the Schiff base increased on complexation with the metal ion. In vitro antitumor activity assayed against five human tumor cell lines furnished the significant toxicities of the Schiff base and its complexes.  相似文献   

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