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1.
Co(II), Ni(II), and Cu(II) complexes, ML2 · 2H2O have been synthesized with Schiff bases derived from m-substituted thiosemicarbazides and 2-methoxy benzaldehyde. The complexes are soluble in DMF/DMSO and non-electrolytes. From analytical, spectral (IR, UV-Vis, ESR, and FAB-mass), magnetic and thermal studies octahedral geometry is proposed for the complexes. The redox behavior of the complexes was investigated using cyclic voltammetry. The Schiff bases and their metal complexes have been screened for antibacterial (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella typhi) and antifungal activities (Aspergillus niger, Aspergillus flavus, and Cladosporium) by Minimum Inhibitory Concentration method. DNA cleavage is studied by agarose gel electrophoresis method.  相似文献   

2.
A series of Co(II), Ni(II), and Cu(II) complexes have been synthesized with Schiff bases (H2LI and H2LII) derived from 8-formyl-7-hydroxy-4-methylcoumarin or 5-formyl-6-hydroxycoumarin and o-aminophenol. Structures have been proposed from elemental analyses, spectral (IR, UV-Vis, FAB-mass, and Fluorescence), magnetic, and thermal studies. The measured low molar conductance values in DMF indicate that the complexes are non-electrolytes. Elemental analyses indicate ML · 3H2O [M = Co(II), Ni(II), and Cu(II)] stoichiometry. Spectroscopic studies suggest coordination through azomethine nitrogen, phenolic oxygen of o-aminophenol, and the coumarin via deprotonation. The Schiff bases and their complexes have been screened for antibacterial (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella typhi) and antifungal (Aspergillus niger, Aspergillus flavus, and Cladosporium) activities by minimum inhibitory concentration (MIC) method. The redox behavior of the complexes was investigated using cyclic voltammetry (CV).  相似文献   

3.
New Schiff bases have been synthesized from benzofuran-2-carbohydrazide and benzaldehyde, [BPMC] or 3,4-dimethoxybenzaldehyde, [BDMeOPMC]; complexes of the type MLX2, where M = Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II), L = BPMC or BDMeOPMC and X = Cl, have been prepared. Structures have been elucidated on the basis of elemental analysis, conductance measurements, magnetic properties, spectral studies i.e., 1H NMR, electronic, ESR and IR studies show that the Schiff bases are bidentate through the azomethine nitrogen and oxygen of the carbonyl. We propose tentative structures for all of these complexes. The antifungal and antibacterial activities of the ligands and their metal complexes have been screened against fungi Aspergillus niger and Aspergillus fumigatus and against bacteria Escherichia coli and S. aurious.  相似文献   

4.
A series of Co(II), Ni(II) and Cu(II) complexes, [ML?·?2H2O] of Schiff bases derived from 4,4-diaminodiphenyl sulfone (dapsone) and 8-formyl-7-hydroxy-4-methylcoumarin/5-formyl-6-hydroxycoumarin have been synthesized. From analytical, spectral (IR, NMR, UV-Vis, ESR and FAB mass), and magnetic studies it has been concluded that the metal complexes possess octahedral geometry and are non-electrolytes. The redox behavior of the metal complexes is investigated by cyclic voltammetry. The Schiff bases and their metal complexes have been screened for antibacterial (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella, Salmonella, Streptococcus, Staphylococcus proteus) and antifungal activities (Fusarium, Candida, Rhizopus, Penicillium chrysogenum and Aspergillus niger) by the minimum inhibitory concentration method. The anthelmintic activity of the ligands and their metal complexes against earthworms was investigated. The DNA cleavage study was done by agarose gel electrophoresis. Anti-inflammatory activity studies showed the test compounds are comparable to the standard drug diclofenac sodium.  相似文献   

5.
A series of metal complexes of Co(II), Ni(II) and Cu(II) have been synthesized with the Schiff base derived from thiocarbohydrazide and 8-formyl-7-hydroxy-4-methylcoumarin. The structures of the complexes have been proposed by elemental analyses, molar conductance, spectral (IR, UV-Vis, ESR and FAB-mass), magnetic, thermal and electrochemical studies. These complexes are soluble in DMF and DMSO and molar conductance values indicate that they are non-electrolytes. Elemental analyses of the complexes confirm stoichiometry ML ·; 2H2O [M=Co(II), Ni(II) and Cu(II)]. Spectroscopic studies indicate coordination occurs through phenolic oxygen after deprotonation and nitrogen of azomethine. The Schiff base and its complexes have also been screened for antibacterial (Escherichia coli, Streptococcus aureus, Streptococcus pyogenes and Pseudomonas aeruginosa) and antifungal activities (Aspergillus niger, Aspergillus flavus and cladosporium) by the MIC method. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic properties.  相似文献   

6.
A series of metal complexes of cobalt(II), nickel(II), copper(II), and zinc(II) have been synthesized with newly-derived biologically active ligands. These ligands were synthesized by condensation of 3-substituted-4-amino-5-hydrazino-1,2,4-triazole and orthophthalaldehyde. The probable structure of the complexes has been proposed on the basis of elemental analyses and spectral (IR, 1H-NMR, UV-vis, magnetic, ESR, FAB-mass and thermal studies) data. Electrochemical study of the complexes is also made. All complexes are nonelectrolytes in N,N-dimethyl formamide and DMSO. The Schiff bases and their Co(II), Ni(II), Cu(II), and Zn(II) complexes have been screened for antibacterial (Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, and Pseudomonas aeruginosa) and antifungal (Aspergillus niger, Aspergillus flavus, and cladosporium) activities by minimum inhibitory concentration method. DNA cleavage is also carried out.  相似文献   

7.
A series of Co(II), Ni(II) and Cu(II) complexes have been synthesized with Schiff bases derived from 8-formyl-7-hydroxy-4-methyl coumarin and o-chloroaniline/o-toluidine. The structures of the complexes have been proposed from analytical, spectral (IR, UV-Vis, ESR and FAB-mass), magnetic, thermal and fluorescence studies. The complexes are soluble in DMF and DMSO and molar conductance values indicate the complexes are non-electrolytes. Elemental analyses indicate ML2 · 2H2O [M = Co(II), Ni(II) and Cu(II)] stoichiometry. Spectroscopic studies (IR, UV-Vis, ESR and fluorescence) indicate octahedral geometry, in which ligand coordinates through azomethine nitrogen and phenolic oxygen via deprotonation. Thermal studies suggest coordination of water to the metal ion. Redox behavior of the complexes was investigated by cyclic voltammetry. The Schiff bases and their complexes were screened for their antibacterial (E. coli, S. aureus, P. aeruginosa and S. typhi) and antifungal activities (A. niger, A. flavus and Cladosporium) by MIC method.  相似文献   

8.
Co(II), Ni(II), Cu(II), and Zn(II) complexes have been prepared with Schiff bases derived from 3-formyl-2-mercaptoquinoline and substituted anilines. The prepared Schiff bases and chelates have been characterized by elemental analysis, molar conductance, magnetic susceptibilities, electronic, IR, 1H-NMR, ESR, cyclic voltammetry, FAB-mass, and thermal studies. The complexes have stoichiometry of the type ML2 · 2H2O coordinating through azomethine nitrogen and thiolate sulfur of 2-mercapto quinoline. An enhancement in fluorescence has been noticed in the Zn(II) complexes whereas quenching occurred in the other complexes. The ligands and their metal complexes have been screened in vitro for antibacterial and antifungal activities by MIC methods with biological activity increasing on complexation. Cu(II) complexes show greater bacterial than fungicidal activities. The brine shrimp bioassay was also carried out to study the in vitro cytotoxicity properties of the ligands and their corresponding complexes. Only four compounds have exhibited potent cytotoxic activity against Artemia salina; the other compounds were almost inactive for this assay.  相似文献   

9.
A series of cobalt(II), nickel(II) and copper(II) complexes have been synthesized with Schiff bases derived from 3-substituted-4-amino-5-mercapto-1,2,4-triazole and indole-3-aldehyde in ethanol. These complexes have been characterized by elemental analyses, magnetic, spectroscopic (IR, UV-Vis, H-NMR, ESR, FAB-mass), thermal, electrochemical (CV) and solid state d.c. electrical conductivity studies. The elemental analyses confirm 1 : 2 stoichiometry of the type ML2·2H2O (M = Co/Ni) and ML2 (M=Cu). The complexes are colored solids and non-electrolytes in DMF and DMSO. Magnetic and spectral data suggest octahedral geometry for Co(II) and Ni(II) complexes and square-planar geometry for Cu(II) complexes. The presence of coordinated water in Co(II) and Ni(II) complexes was confirmed by thermal and IR data of the complexes. The complexes are insoluble in water and common organic solvents and decompose at higher temperature. All these ligands and their complexes have also been screened for antibacterial (Bacillus cereus, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) and antifungal activities (Aspergillus niger and Aspergillus fumigates) by the cup plate method.  相似文献   

10.
New Schiff bases, N,N′-bis(salicylidene)-4-aminobenzylamine (H2L1), N,N′-bis(3-methoxysalicylidene)-4-aminobenzylamine (H2L2), and N,N′-bis(4-hydroxysalicylidene)-4-aminobenzylamine (H2L3), with their nickel(II), cobalt(II), and copper(II) complexes have been synthesized and characterized by elemental analyses, electronic absorption, FT-IR, magnetic susceptibility, and conductance measurements. For the ligands, 1H and 13C NMR and mass spectra were obtained. The tetradentate ligands coordinate to the metal ions through the phenolic oxygen and azomethine nitrogens. The keto-enol tautomeric forms of the Schiff bases H2L1, H2L2, and H2L3 have been investigated in polar and apolar solvents. All compounds were non-electrolytes in DMSO (~10?3 M) according to the conductance measurements. Antimicrobial activities of the Schiff bases and their complexes have been tested against Acinobacter baumannii, Pseudomonas aeruginosa, Micrococcus luteus, Bacillus megaterium, Corynebacterium xerosis, Staphylococcus aureus, Escherichia coli, Candida albicans, Rhodotorula rubra, and Kluyveromyces marxianus by the disc diffusion method; biological activity increases on complexation.  相似文献   

11.
Two new hexadentate N2O4 donor Schiff bases, H4L1 and H4L2, were synthesized by condensation of 4,6-diacetylresorcinol with glycine and alanine, respectively. The structures of the ligands were elucidated by elemental analyses, IR, 1H NMR, electronic, and mass spectra. Reactions of the Schiff bases with copper(II), nickel(II), and iron(III) nitrates in 1 : 2 molar ratio gave binuclear metal complexes and, in the presence of 8-hydroxyquinoline (8-HQ) or 1,10-phenanthroline (Phen) as secondary ligands (L′), mixed-ligand complexes in two molar ratios 1 : 2 : 2 and 1 : 2 : 1 (L1/L2 : M : L′). The complexes were characterized by elemental and thermal analyses, IR, electronic, mass, and ESR spectral studies, as well as conductivity and magnetic susceptibility measurements. The spectroscopic data reveal that the Schiff-base ligands were dibasic or tetrabasic hexadentate ligands. The coordination sites with the metal ions are two azomethine nitrogens, two oxygens of phenolic groups, and two oxygens of carboxylic groups. Copper(II) complexes were octahedral and square planar while nickel(II) and iron(III) complexes were octahedral. The Schiff bases, H4L1 and H4L2, and some of their metal complexes showed antibacterial activity towards Gram-positive (Staphylococcus aureus and Streptococcus pyogenes) and Gram-negative (Pseudomonas fluorescens and Pseudomonas phaseolicola) bacteria and antifungal activity towards the fungi Fusarium oxysporium and Aspergillus fumigatus.  相似文献   

12.
Summary Metal(II) chelates of Schiff bases derived from the condensation of 1,2,3,5,6,7,8,8a-octahydro-3-oxo-N,1-diphenyl-5-(phenylmethylene)-2-naphthalenecarboxamide with o-aminophenol (KAAP), o-aminothiophenol (KAAT) or o-aminobenzoic acid (KAAB) have been prepared and characterized. The complexes are of the type [M(N2X)]2 for M = CuII and M(NX)2·nH2O for M = NiII, CoII and VOII (X = phenolic oxygen, thiophenolic sulphur or carboxylic oxygen; n = 0 or 2). Conductivity data indicate that the complexes are non-ionic. The Schiff bases behave as dibasic tridentate ligands in their copper(II) complexes and as monobasic bidentate ligands in their nickel(II), cobalt(II) and vanadyl(II) complexes. The subnormal magnetic moments of the copper(II) complexes are ascribed to an antiferromagnetic exchange interaction arising from dimerization. Nickel(II) and cobalt(II) complexes are trans octahedral whereas vanadyl(II) complexes are square pyramidal  相似文献   

13.
Complexes of Cu(II), Ni(II) and Co(II) with the Schiff bases derived from o-aminobenzoic acid with salicylaldehyde and its 5-chloro and 5-bromo derivatives have been prepared. The 1:1 (metal-ligand) stoichiometry of these complexes is shown by elemental analysis, gravimetric estimations and conductometric titrations while the structures of the complexes are proved by i.r. spectra and thermogravimetric analysis. The magnetic susceptibility and electronic spectra of Cu(II) complexes indicate the nonplanar binuclear structures while that of Ni(II) and Co(II) show their paramagnetic octahedral geometry. The molar conductance values in nitrobenzene indicate the nonelectrolytic behaviour of the complexes. The results show that the complexes of the type (Cu·L)2, Ni·L·3H2O and Co·L·3H2O are formed having solvent molecule in coordination with the metal ion. The monopyridine and monoammonia adducts of Cu(II) complexes were found to be monomeric.  相似文献   

14.
Summary The syntheses of several new coordination complexes of nickel(II), cobalt(II), manganese(II), copper(II), zinc(II), dioxouranium(VI) and dioxomolybdenum(VI) with new Schiff bases derived from 2-benzothiazolecarbohydrazide and salicylaldehyde or 2-hydroxy-1-naphthaldehyde are described. These complexes have been characterised by elemental analyses, electrical conductance, magnetic susceptibility, molecular weight, i.r. and electronic spectra. The Schiff bases behave as dibasic and tridentate ligands coordinating through the ONO donor system and form complexes of the types NiL · 3H2O, MnL · 2H2O, CoL · 2H2O, CuL, ZnL · H2O, UO2L · MeOH and MoO2L · MeOH (where LH2 = Schiff base). The copper(II) complexes exhibit subnormal magnetic moments indicating the presence of an antiferromagnetic exchange interaction, whereas the nickel(II), cobalt(II) and manganese(II) complexes behave normally at room temperature. Zinc(II), dioxouranium(VI) and dioxomolybdenum(VI) complexes are diamagnetic; the zinc (II) complexes are tetrahedral, the copper(II) complexes are square planar, all the other complexes are octahedral. Thev(C=N),v(C-O),v(N-N) andv(C-S) shifts have been measured in order to locate the Schiff base coordination sites.  相似文献   

15.
A series of metal complexes of Zn(II) have been synthesized with newly synthesized biologically active 1,2,4-triazole Schiff bases derived from the condensation of 3-substituted-4-amino-5-mercapto-1,2,4-triazole with 8-formyl-7-hydroxy-4-methylcoumarin. The structure of the complexes has been proposed in the light of elemental analyses, spectroscopic data (IR, UV-Vis, 1H NMR and FAB-mass), thermal studies. Electrochemical study of the complexes is also reported. All the complexes are soluble to limited extent in common organic solvents but soluble to larger extent in DMF and DMSO and are non-electrolytes in these two solvent. All these Schiff bases and their complexes have also been screened for their antibacterial (Escherichia. coli, S. aureus, S. pyogenes, P. aeruginosa and Salmonella typhi) and antifungal activities (Aspergillus niger, Aspergillus flavus and cladosporium) by MIC method. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic properties.  相似文献   

16.
New series of Schiff bases derived from o‐substituted thiosemicarbazides and 8‐formyl‐7‐hydroxy‐4‐methylcoumarin have been synthesized and their coordination tendency toward Co(II), Ni(II), and Cu(II) metal ions is studied. Analytical, spectral (IR, UV‐Vis, ESR, and FAB‐mass), magnetic, and thermal studies suggests octahedral geometry of the type ML2 for all the Co(II), Ni(II), and Cu(II) complexes. The complexes are soluble in DMF/DMSO and are non‐electrolytes. The Schiff bases and their metal complexes have been screened for antibacterial (Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa) and antifungal activities (Aspergillus flavus, Aspergillus niger, and Cladosporium) by minimum inhibitory concentration method. DNA cleavage is studied by agarose gel electrophoresis method. Metal (II) complexes show good anthelmintic activity when compared to Schiff bases.  相似文献   

17.
Neutral complexes of Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized from the Schiff bases derived from 3-nitrobenzylidene-4-aminoantipyrine and aniline (L1)/p-nitro aniline (L2)/p-methoxy aniline (L3) in the molar ratio 1 : 1. The structural features have been determined from microanalytical, IR, UV-Vis, 1H-NMR, mass, and ESR spectral data. The Cu(II) complexes are square planar, while Co(II), Ni(II), and Zn(II) complexes are tetrahedral. Magnetic susceptibility measurements and molar conductance data provide evidence for the monomeric and neutral nature of the complexes. The X-band ESR spectrum of Cu(II) complexes at 300 and 77 K were recorded. The electrochemical behavior of the complexes in MeCN at 298 K was studied. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola, and Candida albicans by the well-diffusion method. Comparison of the inhibition values of the Schiff bases and their complexes indicate that the complexes exhibit higher antimicrobial activity.  相似文献   

18.
Ni(II), Cu(II), and Zn(II) complexes with bidentate Schiff bases derived from the condensation reaction of 5-chlorosalicylaldehyde, 5-nitrosalicylaldehyde, and 3,5 ditertiarybutyl-2-hydroxy benzaldehyde with tryptamine, have been reported. The ligands and complexes were characterized by elemental analysis, IR, 1H NMR and UV–Vis spectroscopy as well as single crystal X-ray structure analysis whenever possible. The complexes were found to have the general formula [M(L)2]. Spectral studies reveal that these Schiff bases were acting as bidentate ligands and co-ordinating to the metal center through deprotonated phenolate oxygen and azomethine nitrogen atoms. The Zn(II) complexes establish a tetrahedral geometry in a 1:2 metal to ligand stoichiometry, whereas a square planar geometry was proposed for the nickel and copper complexes, slightly distorted in the case of the latter.The antiulcer activity of 5-chlorosalicylaldehyde derivative and its nickel and copper complexes were evaluated in ethanol-induced gastric mucosal injury in rats. This Schiff base and its complexes promote ulcer protection as ascertained by the comparative decrease in ulcer areas, and inhibition of edema and leucocyte infiltration of the submucosal layer.  相似文献   

19.
A series of Cu(II), Co(II), and Ni(II) complexes of bis-(3,5-dimethyl-pyrazolyl-1-methyl)-(3-phosphanyl-propyl)-amine C15H26N5P (1), prepared from 3-aminopropylphosphine and 1-hydroxymethyl-3,5-dimethylpyrazole were characterized. The nature of bonding and the geometry of the complexes have been deduced from elemental analysis, infrared, electronic, 1H NMR, 31P NMR spectra, magnetic susceptibility, and conductivity measurements. The studies indicate octahedral geometry for nickel complex and square pyramidal geometry for copper and cobalt complexes. The EPR spectra of copper complex in acetonitrile at 300 K and 77 K were recorded. Biological activities of the ligand and metal complexes have been studied on Staphylococcus aureus, Escherichia coli, Aspergillus niger, and Aspergillus flavus by well-diffusion method. The zone of inhibition values were measured at 37°C for a period of 24 h. The electrochemical behavior of copper complexes was studied by cyclic voltammetry. Catalytic study indicates the copper complex has efficient catalytic activity in oxidation of amitriptyline.  相似文献   

20.
Four new nickel(II), zinc(II), and cobalt(II) complexes, [Zn(L1)2]?·?H2O (1), [Ni(L1)2]?·?H2O (2), [Ni(L2)2] (3), and [Co(L3)2]?·?H2O (4), derived from hydroxy-rich Schiff bases 2-{[1-(5-chloro-2-hydroxyphenyl)methylidene]amino}-2-methylpropane-1,3-diol (HL1), 2-{[1-(2-hydroxy-3-methoxyphenyl)methylidene]amino}-2-ethylpropane-1,3-diol (HL2), and 2-{[1-(5-bromo-2-hydroxyphenyl)methylidene]amino}-2-methylpropane-1,3-diol (HL3) have been synthesized and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray determination. Each metal in the complexes is six-coordinate in a distorted octahedral coordination. The Schiff bases coordinate to the metal atoms through the imino N, phenolate O, and one hydroxyl O. In the crystal structures of HL1 and the complexes, molecules are linked through intermolecular O–H···O hydrogen bonds, forming 1-D chains. The urease inhibitory activities of the compounds were evaluated and molecular docking study of the compounds with the Helicobacter pylori urease was performed.  相似文献   

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