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1.
Four water soluble azo dyes, 4-(isopropyl)-2-[(E)-(4-chlorophenyl)diazenyl]phenol (L 1), 4-(isopropyl)-2-[(E)-(2,4-dichlorophenyl)diazenyl]phenol (L2), 4-(sec-butyl)-2-[(E)-(4-chlorophenyl) diazenyl]phenol (L 3), 4-(sec-butyl)-2-[(E)-(2,4-dichlorophenyl)diazenyl]phenol (L 4), and their Cu(II) and Ni(II) complexes were synthesized and characterized using spectroscopic methods. Examination of their thermal stability revealed similar decomposition temperature of approximately 260–300°C and that they were more thermally stable than their metal complexes. Ni(II) complexes of ligands L2 and L4 were more stable than the other coordination compounds. Among the synthesized ligands, L2 and the complexes Cu(L3)2 and Ni(L4)2 showed both antimicrobial and antifungal activity. However, the other ligands and the complexes were poorly active against selected microorganisms.  相似文献   

2.
Some metal complexes of Schiff bases have been prepared by the interactions of palladium(II) and platinum(II) chloride with 5-chloro-1,3-dihydro-3-[2-(phenyl)-ethylidene]-2H-indol-2-one-hydrazinecarbothioamide(L1H) and 5-chloro-1,3-dihydro-3-[2-(phenyl)-ethylidene]-2H-indol-2-one-hydrazinecarboxamide(L2H), in bimolar ratios. All the new compounds have been characterized by elemental analyses, conductance measurements, molecular weight determinations, IR and 1H NMR spectral studies. The spectral data are consistent with a square planar geometry around Pd(II) and Pt(II) in which the ligands act as neutral bidentate and monobasic bidentate ligands, coordinating through the nitrogen and sulfur/oxygen atoms. Free ligands and their metal complexes were screened for their antimicrobial activity on different species of pathogenic fungi and bacteria and their biopotency has been discussed.  相似文献   

3.
In the current work, two triazine‐based multidentate ligands (H2L1 and H2L2) and their homo‐dinuclear Mn (II), mononuclear Ln (III) and hetero‐dinuclear Mn (II)/Ln (III) (Where Ln: Eu or La) complexes were synthesized and characterized by spectroscopic and analytical methods. Single crystals of a homo‐dinuclear Mn (II) complex {[Mn (HL1)(CH3OH)](ClO4·CH3OH}2 ( 1 ) were obtained and the molecular structure was determined by X‐ray diffraction method. In the structure of the complex, each Mn (II) ion is seven‐coordinate and one of the phenolic oxygen bridges two Mn (II) centre forming a dimeric structure. The UV–Vis. and photoluminescence properties of synthesized ligands and their metal complexes were investigated in DMF solution and the compounds showed emission bands in the UV–Vis. region. The catecholase enzyme‐like activity of the complexes were studied for 3,5‐DTBC → 3,5‐DTBQ conversion in the presence of air oxygen. Homo‐dinuclear Mn (II) complexes ( 1 and 4 ) were found to efficiently catalyse 3,5‐DTBC → 3,5‐DTBQ conversion with the turnover numbers of 37.25 and 35.78 h?1 (kcat), respectively. Mononuclear Eu (III) and La (III) complexes did not show catecholase activity.  相似文献   

4.
A new series of metal complexes of salicyladimine ligands with Pd(II) and Co(II) have been prepared and characterized by different techniques (elemental analysis, UV-vis, FT-IR, 1H NMR spectra, magnetic susceptibility measurements). Electronic spectra and magnetic susceptibility measurements reveal square planar geometry for Pd(II) metal complex and tetrahedral geometry for Co(II) metal complex. The synthesized Pd(II) and Co(II) complexes were also tested as catalysts for the formation of cyclic organic carbonates from carbon dioxide and liquid epoxides which served as both reactant and solvent. The results showed that the [M(L3)2] (M = Pd or Co) complexes bearing 5-methyl substituent on the aryl ring are more efficient than the other Pd(II) and Co(II) metal complexes for the formation of cyclic organic carbonates from carbon dioxide. These catalysts, [Pd(L3)2] and [Co(L3)2] complexes and location (p-position of phenoxy) of electron donating methyl substituent in particular, effectively promote the of carbon dioxide activation with liquid epoxides under solvent-free homogeneous conditions. Furthermore, [Pd(L3)2] can be reused more than eight times with a minimal loss of its original catalytic activities.  相似文献   

5.
The 12- and 14-membered diazadioxo macrocyclic ligands, 1,2?:?7,8-diphenyl-6,9-diaza-3,12-dioxocyclododecane (L1) and 1,2?:?8,9-diphenyl-7,10-diaza-3,14-dioxocyclotetradecane (L2), were synthesized by condensation between o-phenylenediamine, 1,2-dibromoethane/1,3-dibromopropane, and catechol. Metal complexes [ML1Cl2] and [ML2Cl2] [M?=?Co(II), Ni(II), Cu(II), and Zn(II)] were prepared by interaction of L1 or L2 with metal(II) chlorides. The ligands and their complexes were characterized by elemental analyses, IR, 1H, and 13C NMR, EPR, UV-Vis spectroscopy, magnetic susceptibility, conductivity measurements, and Electrospray ionization-mass spectral (ESI-MS) studies. The results of elemental analyses, ESI-MS, Job's method, and conductivity measurements confirmed the stoichiometry of ligands and their complexes while absorption bands and resonance peaks in IR and NMR spectra confirmed the formation of ligand framework around the metal ions. Stereochemistry was inferred from the UV-Vis, EPR, and magnetic moment studies.  相似文献   

6.
Complexes of Cr(III) and Mn(II) with N′,N″-bis(3-carboxy-1-oxopropanyl) 2-amino-N-arylbenzamidine (H2L1) and N′,N″-bis(3-carboxy-1-oxophenelenyl) 2-amino-N-arylbenzamidine (H2L2) have been synthesized and characterized by various physico-chemical techniques. The vibrational spectral data are in agreement with coordination of amide and carboxylate oxygen of the ligands with the metal ions. The electronic spectra indicate octahedral geometry around the metal ions, supported by magnetic susceptibility measurements. The thermal behavior of chromium(III) complexes shows that uncoordinated nitrate is removed in the first step, followed by two water molecules and then decomposition of the ligand; manganese(II) complexes show two waters removed in the first step, followed by removal of the ligand in subsequent steps. Kinetic and thermodynamic parameters were computed from the thermal data using Coats and Redfern method, which confirm first order kinetics. The thermal stability of metal complexes has been compared. X-ray powder diffraction determines the cell parameters of the complexes.  相似文献   

7.
The hepta- and octa-dentate ligands N,N′-bis(2-aminobenzyl)-1,10-diaza-15-crown-5 (L1) and N,N′-bis(2-aminobenzyl)-1,10-diaza-18-crown-6 (L2), respectively, form stable mononuclear Mn(II) complexes. Spectrophotometric titrations performed in acetonitrile solution indicate the formation of mononuclear Mn(II) complexes with both ligands, and no evidence for the formation of binuclear complexes was obtained. The optimal architecture of L1 allows it to impose the less usual pentagonal bipyramidal geometry on the Mn(II) guest, and the X-ray crystal structure of [Mn(L1)](ClO4)2 shows that the Mn(II) ion is deeply buried in the receptor cavity, coordinated to the seven available donor atoms, with the perchlorate anions remaining outside the metal coordination sphere. In spite of its higher denticity, the receptor L2 is unable to form the expected binuclear complexes. The X-ray crystal structure of [Mn(L2)](NO3)2 consists of the [Mn(L2)]2+ cation and nitrate anions involved in hydrogen-bonding interactions with the aniline groups. In [Mn(L2)]2+ the metal ion is also placed in the crown hole, but as a result of the large size of the macrocyclic cavity only six of the eight available donor atoms of the receptor form part of the Mn(II) coordination sphere, with the Mn(II) ion found in a distorted octahedral coordination environment.  相似文献   

8.
In the present study, two new ligands, 4-chlorobenzal-azino-isonitrosoacetophenone (L1), 4-methylbenzal-azino-isonitrosoacetophenone (L2) and their metal complexes were synthesized using acetophenone as a starting material. The coloured complexes were prepared by the addition of chloride salts of Ni(II), Co(II), Cu(II) and Zr(IV) ions to a solution of ligands. In conclusion, the structures of the obtained ligands and their complexes were characterized by FT-IR, and 1H NMR spectra, AAS (atomic absorption spectrum) analysis, magnetic susceptibilities as well as elemental analysis.  相似文献   

9.
Complexes of Mn(II), Co(II), Ni(II), Pd(II) and Pt(II) were synthesized with the macrocyclic ligand, i.e., 2,3,9,10-tetraketo-1,4,8,11-tetraazacycoletradecane. The ligand was prepared by the [2 + 2] condensation of diethyloxalate and 1,3-diamino propane and characterized by elemental analysis, mass, IR and 1H NMR spectral studies. All the complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, IR, electronic and electron paramagnetic resonance spectral studies. The molar conductance measurements of Mn(II), Co(II) and Ni(II) complexes in DMF correspond to non electrolyte nature, whereas Pd(II) and Pt(II) complexes are 1:2 electrolyte. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II), Co(II) and Ni(II) complexes, whereas square planar geometry assigned for Pd(II) and Pt(II). In vitro the ligand and its metal complexes were evaluated against plant pathogenic fungi (Fusarium odum, Aspergillus niger and Rhizoctonia bataticola) and some compounds found to be more active as commercially available fungicide like Chlorothalonil.  相似文献   

10.
Abstract

The formation of two complexes by reaction of [PdCl4]2- with 1,2,3-triphenylguanidine (PhNH)2C=NPh under different metal/ligand ratios has been observed and the structure of the complex [(1,2,3-triphenylguanidine)2PdCl2] has been determined by X-ray diffraction methods. The ligands are coordinated as neutral monodentate molecules to the metal centre through their imine nitrogen atoms. The second Pd(II) complex is [Pd(1,2,3-triphenylguanidine)4]2+ and was isolated by precipitation with ClO? 4.  相似文献   

11.
Abstract

Five coordination complexes with Mn2+ (1), Co2+ (2), Ni2+ (3), Cu2+ (4), and Zn2+ (5) containing acesulfame (ace) and N,N-diethylnicotinamide (dena) ligands were synthesized and structural binding properties investigated. Four compounds (1, 2, 4, and 5) were examined with single crystal X-ray diffraction methods. The structures containing Mn(II), Co(II), and Zn(II) were iso-structural. Six-coordination of metal cations were completed with two moles dena and four aqua ligands. The dena ligands were coordinated via pyridine nitrogen as neutral-monodentate. Charge stabilities of the complexes are complemented by two moles monoanionic ace ligands, located outside of the coordination unit. In the Cu(II) complex, the coordination is completed by acidic nitrogen and carbonyl oxygen atoms of two ace ligands and pyridine nitrogen of two moles dena ligands. The coordination to Cu(II) for ace ligands was monoanionic-bidentate. All metal cations in the structure are distorted octahedral. Thermal decomposition of complexes begins with removal of the aqua molecules from the structures and is completed by combustion of organic ligands. The final decomposition products of all structures have been identified as corresponding metal oxides. Some biological applications (anti-fungal/anti-bacterial) were studied using 15.  相似文献   

12.
Mn(II), Co(II), Ni(II), Cu(II), Pd(II) and Ru(III) complexes of Schiff bases derived from the condensation of sulfaguanidine with 2,4‐dihydroxy benzaldehyde ( HL1 ), 2‐hydroxy‐1‐naphthaldehyde ( HL2 ) and salicylaldehyde ( HL3 ) have been synthesized. The structures of the prepared metal complexes were proposed based on elemental analysis, molar conductance, thermal analysis (TGA, DSC and DTG), magnetic susceptibility measurements and spectroscopic techniques (IR, UV‐Vis, and ESR). In all complexes, the ligand bonds to the metal ion through the azomethine nitrogen and α‐hydroxy oxygen atoms. The structures of Pd(II) complex 8 and Ru(III) complex 9 were found to be polynuclear. Two kinds of stereochemical geometries; distorted tetrahedral and distorted square pyramidal, have been realized for the Cu(II) complexes based on the results of UV‐Vis, magnetic susceptibility and ESR spectra whereas octahedral geometry was predicted for Co(II), Mn(II) and Ru(III) complexes. Ni(II) complexes were predicted to be square planar and tetrahedral and Pd(II) complexes were found to be square planar. The antimicrobial activity of the ligands and their metal complexes was also investigated against the gram‐positive bacteria Staphylococcus aures and Bacillus subtilis and gram‐negative bacteria, Escherichia coli and Pesudomonas aeruginosa, by using the agar dilution method. Chloramphenicol was used as standard compound. The obtained data revealed that the metal complexes are more or less, active than the parent ligand and standard. The X‐ray crystal structure of HL3 has been also reported.  相似文献   

13.
New mixed-ligand complexes with empirical formulae M(4-bpy)L2·1.5H2O (M(II)=Mn, Co), Ni(4-bpy)2L2 and Cu(4-bpy) L2·H2O (where: 4-bpy=4,4'-bipyridine, L=CC L2HCOO-) have been isolated in pure state. The complexes have been characterized by elemental analysis, ir spectroscopy, conductivity (in methanol, dimethylformamide and dimethylsulfoxide solutions) and magnetic and x-ray diffraction measurements. The Mn(II) and Co(II) complexes are isostructural. The way of metal-ligand coordinations discussed. the ir spectra suggest that the carboxylate groups are bonded with metal(II) in the same way (Ni, Cu) or in different way (Mn, Co). The solubility in water is in the order of 19.40·10-3÷1.88·10-3ł mol dm-3ł. During heating the hydrate complexes lose all water in one step. The anhydrous complexes decompose to oxides via several intermediate compounds. A coupled TG-MS system was used to analyse the principal volatile products of obtained complexes. The principal volatile products of thermal decomposition of complexes in air are: H2O2 +, CO2 +, HCl+, Cl2 +, NO+ and other. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
The synthesis and physico-chemical characterization of Fe(II) and Mn(II) complexes of 2-[4,6-di(tert-butyl)-2,3-dihydroxyphenylsulfanyl]acetic acid (HLI) and 2-[4,6-di(tert-butyl)-2,3-dihydroxyphenylsulfinyl]acetic acid (HLII) were carried out. The investigation of the molecular and electronic structure of Cu(II), Ni(II), Zn(II), Fe(II) and Mn(II) complexes has been performed within the density functional theory (DFT) framework. The computed properties were compared to the experimental ones, and molecular structures of the compounds were proposed based on the array of spectral data and quantum chemical calculations. Antibacterial activity of the Fe(II) and Mn(II) complexes was evaluated in comparison with Cu(II), Co(II), Ni(II) and Zn(II) complexes and three standard antibiotics; it was found to follow the order: (1) Сu(LI)2 > Mn(LI)2 > HLI > Ni(LI)2 > Zn(LI)2 > Fe(LI)2 > Co(H2O)2LI; (2) Cu(LII)2 > Сo(LII)2 > Ni(LII)2 > Mn(H2O)2(LII)2 > Fe(LII)2 > HLII > Zn(LII)2; their reducing ability (determined electrochemically) followed the same order. Spectrophotometric investigation was carried out in order to estimate the rate of the reduction of bovine heart сytochrome c with the ligands and their metal(II) complexes. The complexes Сu(LI)2, Mn(LI)2 and Co(LII)2 with the high reducing ability were found to be characterized by the highest rates of Cyt с reduction. NADPH:cytochrome P450-reductase had no substantial effect on the rate of сytochrome c reduction with HLI and HLII ligands.  相似文献   

15.
Asymmetric bidentate Schiff base ligand (HL) and its cobalt(III), nickel(II), and copper(II) complexes have been synthesized (where L = 2-[(4-methoxy-2-nitrophenyl)iminomethyl]phenol). The ligand and its metal complexes have been characterized by elemental analyses (CHN) and FTIR spectroscopy. Thermogravimetric analyses of the compounds reveal their thermal stabilities along with their thermal decomposition pattern. In addition, the complexes have been used for the preparation of corresponding metal oxide nanoparticles by controlled aerobic thermal decomposed at 500 °C. The FTIR pattern of the obtained solids receals the formation of the metal oxides nanoparticles.  相似文献   

16.
The stoichiometry and stability constants of complexes formed between [Pd(AMBI)(H2O)2]2+ (AMBI?=?2-(aminomethyl)-benzimidazole) with some selected bio-relevant ligands containing different functional groups were investigated at 25°C and 0.1?mol?L?1 ionic strength. The ligands used are imidazole, cysteine, glutathione (GSH), threonine, aspartic acid, 1,1-cyclobutane dicarboxylic acid (CBDCA) and lysine. The stoichiometry and stability constants of the formed complexes were reported and the concentration distribution of the various complex species was evaluated as a function of pH. The results show ring opening of CBDCA and monodentate complexation of the DNA constituent with the formation of [Pd(AMBI)(CBDCA–O)DNA], where (CBDCA–O) represents cyclobutane dicarboxylate coordinated by one carboxylate oxygen. The equilibrium constant of the displacement reaction of coordinated inosine, as a typical DNA constituent, by glutathione, as a typical thiol ligand, was investigated. The effect of dioxane on the formation constant of CBDCA with Pd(AMBI)2+ is reported. Five new palladium(II) complexes of the formula [Pd(AMBI)(AA)] n + (where AMBI?=?2-aminomethyl benzimidazole, AA is an anion of glycine, alanine, cysteine, methionine, and serine) have been synthesized. These palladium(II) complexes have been ascertained by elemental, molar conductance, infrared and 1H-NMR spectroscopy. The isolated Pd(II) complexes were screened for their antibacterial and cytotoxic activities and the results are discussed.  相似文献   

17.
Mn(II), Co(II), Ni(II) and Cu(II) chelates with3-phenyl-4-(p-methoxyphenylazo)-5-pyrazolone have been synthesized and were characterized by elemental and thermal analyses as well as by IR, UV-VIS, 1HNMR, conductometric and magnetic measurements. The first stage in the thermal decomposition process of these complexes shows the presence of water of hydration, the second denotes the removal of the coordinated water molecules. The final decomposition products were found to be the respective metal oxides. The data of the investigated complexes suggest octahedral geometry with respect to Co(II) 1:1, tetrahedral for Ni(II) 1:1and 2:3; square planar for Cu(II) 1:1 and 2:3; the complexes with no coordinated water molecules (2:3) Co(II) and Mn(II) complexes are tetrahedral. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
The potassium salt of salicylidene-DL-alanine (KHL), bis(benzylidene)ethylenediamine (A1), thiophene-o-carboxaldene-p-toluidine (A2), and its metal complexes of the formula [(MII(L)(A)(H2O)] (M = Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II); A = A1 or A2) are prepared. They are characterized by elemental analysis, magnetic susceptibility measurements, thermogravimetric analysis, and infrared and electronic spectral studies. The electronic spectral and magnetic moment data suggest an octahedral geometry for the complexes. All of these complexes, metal nitrates, fungicides (bavistin and emcarb), and ligands are screened for their antifungal activity against Aspergillus niger, Fusarium oxysporum, and Aspergillus flavus using a plate poison technique. The complexes show higher activity than those of the free ligands, metal nitrate, and the control (DMSO) and moderate activity against bavistin and emcarb. The text was submitted by the authors in English.  相似文献   

19.
Platinum(IV) and palladium(II) complexes [Pt(L)2Cl2] and [Pd(L)Cl2], [where, L?=?1,1-diphenyl-2-thiosemicarbazide (L1) and (1,1-diphenyl-2-thio)-1,3-propanediamine (L2) have been synthesized. The thiosemicarbazides and thiodiamines exist as the thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands are monobasic bidentate. The complexes have been characterized by elemental analysis, IR, mass, electronic and 1H NMR spectroscopic studies. In vitro antibacterial studies have also been carried out for some complexes.  相似文献   

20.
Two Schiff base ligands, 2-{E-[(5-phenyl-6H-1,3,4-thiadiazin-2yl)imino]methyne}-1-naphthol (L1H) and 5-nitro-2-{[(5-phenyl-6H-1,3,4-thiadiazin-2-yl)imino]methyne}phenol (L2H) have been prepared from 5-phenyl-6H-1,3,4-thiadiazin-2-amine (A), 2-hydroxynaphthaldehyde (1) and 2-hydroxy-5-nitrobenzaldehyde (2) Mononuclear Co(II), NiII and CuII complexes of the ligands have been prepared by using CoII, NiII and CuII salts with a 1:2 metal:ligand ratio. It was determined that the bidentate behavior of the ligands is accomplished via the phenolic oxygen and the azomethine nitrogen atoms. The structures of the ligands and their complexes were identified by using elemental analyses, i.r., 1H-n.m.r. spectra, electronic spectra, magnetic susceptibility measurements and thermogravimetric analyses (t.g.a.).  相似文献   

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