Browsing by Author "Sonmez, Mehmet"

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2,6-Bis((e) and Its Metal(Ii) Complexes: Synthesis, Spectroscopy, Biological Activity, and Photoluminescence Features
(Wiley-v C H verlag Gmbh, 2013) Gulcan, Mehmet; Zengin, Huseyin; Celebi, Metin; Sonmez, Mehmet; Berber, Ismet
The preparation, characterization, magnetic measurements, antimicrobial activity, and photoluminescence properties of a number of metal complexes with a Schiff base ligand derived from 2, 6-diformyl-4-methylphenol and 1-amino-5-benzoyl-4-phenyl-1H-pyrimidine-2-thione are reported herein. UV/Vis spectra and magnetic measurements infer square planar stereochemistry for Pd-II and Pt-II complexes, and octahedral arrangement for the other metal complexes. The compounds results in intense emission (where (max) = 402 nm) upon irradiation by UV light. The photoluminescence quantum yields and long excited-state lifetimes of the ligand and its complexes were calculated as 42% and 3.94 ns, respectively. The photoluminescence intensities and quantum yields of metal complexes changed upon complexation with various metal ions. The ligand and its complexes are of interest as organic emitting materials for electroluminescent devices. The complexes were additionally evaluated for in vitro the antimicrobial activity against bacterial and fungal strains. While Cu-II, Co-II, and Pt-II complexes have good antifungal efficiency against yeast (MICs, 80 gmL(-1)), only the complex [Cu(L)(AcO)]4H(2)O had effective and selective antimicrobial activity against all tested microorganisms with MIC values in the range of 40-80 gmL(-1), except for E. coli ATCC 4230. This study suggests that the complex [Cu(L)(AcO)]4H(2)O may be a new potential antimicrobial substance towards bacteria and fungi.
Metal/Semiconductor Contact Properties of Al/Co(ii)complex Compounds
(Elsevier, 2011) Temirci, Cabir; Gulcan, Mehmet; Goksen, Kadir; Sonmez, Mehmet
A ligand(N-APTH) and Co(II)complex compound of bidentate ligand which contains a ring of the pyrimidine have been produced. For the optical transmission measurements of the Co(II)complex compound thin films, a UV-Visible (UV-Vis) spectrophotometer was employed. As a result of optical measurements. it was revealed that Co(II)complex compound tends to show a semiconductor characteristic with the bandgap value of 3.46 eV. An attempt has been made to explore the rectifying and ohmic properties of Al/Co(II)complex compound/Cu structures assuming that Co(II)complex compound may exhibit a rectifier or ohmic behavior, depending on the fabrication process, when brought into an appropriate contact with a metal. From current-voltage (I-V) measurements, it was found that the device could show good ohmic and rectifying properties intentionally depending on the experimental process followed during fabrication. (C) 2010 Published by Elsevier B.V.
A New Pyrimidine-Derived Ligand, N-Pyrimidine Oxalamic Acid, and Its Cu(Ii), Co(Ii), Mn(Ii), Ni(Ii), Zn(Ii), Cd(Ii), and Pd(Ii) Complexes: Synthesis, Characterization, Electrochemical Properties, and Biological Activity
(Taylor & Francis Ltd, 2010) Sonmez, Mehmet; Celebi, Metin; Levent, Abdulkadir; Berber, Ismet; Senturk, Zuehre
A new heterocyclic compound N-(5-benzoyl-2-oxo-4-phenyl-2H-pyrimidin-1-yl)-oxalamic acid has been synthesized from N-amino pyrimidine-2-one and oxalylchloride. Bis-chelate complexes of the ligand were prepared from acetate/chloride salts of Cu(II), Co(II), Mn(II), Ni(II), Zn(II), Cd(II), and Pd(II) in methanol. The structures of the ligand and its metal complexes were characterized by microanalyses, IR, AAS, NMR, API-ES, UV-Vis spectroscopy, magnetic susceptibility, and thermogravimetric analyses. An octahedral geometry has been suggested for all the complexes, except for Pd(II) complex, in which the metal center is square planar. Each ligand binds using C(2)=O, HN, and carboxylate. The cyclic voltammograms of the ligand and the complexes are also discussed. The new synthesized compounds were evaluated for antimicrobial activities against Gram-positive, Gram-negative bacteria and fungi using the microdilution procedure. The Cu(II) complex displayed selective and effective antibacterial activity against one Gram-positive spore-forming bacterium (Bacillus cereus ATCC 7064), two Gram-positive bacteria (Staphylococcus aureus ATCC 6538 and S. aureus ATCC 25923) at 40-80 mu g mL-1, but poor activity against Candida species. The Cu(II) complex might be a new antibacterial agent against Gram-positive bacteria.
Palladium Nanoparticles Decorated on Amine Functionalized Graphene Nanosheets as Excellent Nanocatalyst for the Hydrogenation of Nitrophenols To Aminophenol Counterparts
(Elsevier Science Bv, 2019) Sogukomerogullari, Hatice Gamze; Karatas, Yasar; Celebi, Metin; Gulcan, Mehmet; Sonmez, Mehmet; Zahmakiran, Mehmet
We reported the improved catalytic property of Pd (0) nanoparticles decorated on amine-functionalized graphene nanosheets (Pd/GNS-NH2) for the hydrogenation of nitrophenol derivatives in the presence of NaBH4 at moderate conditions. Pd/GNS-NH2 nanocatalyst was synthesized by the deposition-reduction method. Sundry techniques such as ICP-OES, P-XRD, XPS, TEM, HR-TEM and EDX have been applied to explain the structure and morphology of the Pd/GNS-NH2 nanocatalyst. The results show that the Pd (0) nanoparticles are perfectly dispersed on the surface of the GNS-NH2 support material (d(mean) = 1.38-2.63 nm). The catalytic activity of the Pd/GNS-NH2 nanocatalyst was tested in the hydrogenation of nitrophenol derivatives in water in the presence of NaBH4 as reductant and the excellent activity of nanocatalyst have been detected against 2-nitrophenol, 4nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol derivatives with 116.8, 65.9, 42.8 and 11.4 min(-1) initial TOF values, respectively. Another important point is that the nanocatalyst has very high reusability performance (at 5th reuse between 71.5 and 91.5%) for the hydrogenation of nitrophenols. Finally, catalytic studies have been carried out at various temperatures to calculate the E-a, Delta H-not equal and Delta S-not equal.
Palladium(Ii) and Platinum(Ii) Complexes of a Symmetric Schiff Base Derived From 2,6,diformyl-4 With N-Aminopyrimidine: Synthesis, Characterization and Detection of Dna Interaction by Voltammetry
(Elsevier France-editions Scientifiques Medicales Elsevier, 2010) Sonmez, Mehmet; Celebi, Metin; Yardim, Yavuz; Senturk, Zuhre
The two new mononuclear complexes were prepared by reacting symmetric Schiff base, containing pyrimidine rings and the metal chlorides of Pd(II) and Pt(II) in methanol. The mononuclear structure of the complexes was confirmed on the basis of elemental analyses, magnetic susceptibility, IR, UV-Vis, NMR, DTA/TGA and API-ES mass spectral data. The interaction of these metal complexes with fish sperm double-stranded DNA (dsDNA) was studied electrochemically based on the oxidation signals of guanine and adenine. Differential pulse (DP) voltammetry by using renewable pencil graphite electrode was employed to monitor the DNA interaction at the surface or in solution. The results indicate that Pd(II) and (Pt) complexes with Schiff base ligand having pyrimidine rings strongly interacted with DNA. (C) 2010 Elsevier Masson SAS. All rights reserved.
Synthesis and Characterization of Co(Ii), Ni(Ii), Cu(Ii) and Zn(Ii) Schiff Base Complexes Derived From Acetylacetone With 1-Amino Pyrimidine-2
(Mrs Pushpa Agarwal, 2006) Sonmez, Mehmet; Haciyusufoglu, M. Emin
Neutral complexes of Co(II), Ni(II), Cu(II) and Zn(II) have been synthesized from the Schiff base derived from acetylacetone and 1-amino-5ben7oyl-4-phenyl-1H pyrimidine-2-one. These complexes have been characterized by elemental and thermal analyses, molar conductivity and magnetic measurements, electronic, IR and H-1, C-13 NMR spectral studies. All of the complexes exhibit octahedral geometry and show non-electrolytic behaviour.
Synthesis and Characterization of Cu(Ii), Ni(Ii), Co(Ii), Mn(Ii), and Cd(Ii) Transition Metal Complexes of Tridentate Schiff Base Derived From O-Vanillin and N-Aminopyrimidine
(Taylor & Francis Ltd, 2011) Gulcan, Mehmet; Sonmez, Mehmet
Monobasic tridentate Schiff base ligand having ONS donor sequence was prepared by condensing N-aminopyrimidine-2-thione with o-vanillin. The complexes were formed by reacting ligand and the metal acetates of Cu(II), Ni(II), Co(II), Mn(II), and Cd(II) in methanol to get a series of mononuclear and dinuclear complexes. The characterization of ligand and metal complexes were carried out by elemental analyses, conductivity measurements, magnetic susceptibility data, FTIR, UV-vis, NMR, and API-ES mass spectral data. The structure of the complexes was confirmed on the basis of elemental analyses, magnetic susceptibility, API-ES mass spectral data and thermal gravitational analysis (TGA).
Synthesis of Some Transition Metal Complexes of Ligands Derived From 5-Phenyl
(Science Reviews 2000 Ltd, 2008) Akbas, Esvet; Sonmez, Mehmet; Celebi, Metin; Aslanoglu, Furgan
A series of amide ligands was prepared by the reactions of 5-phenyl-2,3-dihydro-2,3-furandione and aromatic amines. The ligands reacted with Cu(II) and Ni(II) ions to yield mononuclear complexes. The ligands and complexes were characterised by elemental analyses, mass, FTIR, UV-vis, (1)H NMR and (13)C NMR spectral studies, as well as magnetic moment, AAS and conductance measurements as appropriate.
Synthesis, Characterisation and Antimicrobial Activity 1-Aminopyrimidine and Its Co(Ii), Ni(Ii), Pd(Ii) and Pt(Ii) Complexes
(Science Reviews 2000 Ltd, 2010) Gulcan, Mehmet; Sonmez, Mehmet
Metal complexes of 1-aminopyrimidine-2(1H)-thione were prepared from acetate salts of Co(II), Ni(II), Pd(II) and Pt(II) in methanol. Electronic spectral data and magnetic moment measurements suggest mononuclear square planar geometrical structures for the metal complexes. The ligand and all the metal complexes were evaluated for their antimicrobial activity. The newly synthesised ligand and the Co(II) complex showed moderate activity against all tested bacteria and yeast strains.
Synthesis, Characterization, and Antimicrobial Activity of a New Pyrimidine Schiff Base and Its Cu(Ii), Ni(Ii), Co(Ii), Pt(Ii), and Pd(Ii) Complexes
(Tubitak Scientific & Technological Research Council Turkey, 2012) Gulcan, Mehmet; Sonmez, Mehmet; Berber, Ismet
A new Schiff base, {1-[(5-bromo-2-hydroxy-benzylidene)-amino]-4-phenyl-2-thioxo-1,2-dihyro-pyrimidin-5-yl}-phenyl-methanone, was synthesized from N-amino pyrimidine-2-thione and 5-bromsalicylaldehyde. Metal complexes of the Schiff base were prepared from acetate salts of Cu(II), Ni(II), Co(II), Pd(II), and PtCl2 in methanol. The chemical structures of the Schiff base ligand and its metal complexes were confirmed by spectroscopic analysis. All of the compounds were evaluated for their antimicrobial against 4 gram-positive bacteria, I grain-negative bacterium, and 3 yeast strains. The Schiff base and the Cu(II) and Co(II) complexes showed good biological activity against all tested bacteria and yeast strains.
Synthesis, Characterization, Cyclic Voltammetry, and Antimicrobial Properties of N-(5 Acid and Its Metal Complexes
(Taylor & Francis Ltd, 2010) Sonmez, Mehmet; Celebi, Metin; Levent, Abdulkadir; Berber, Ismet; Senturk, Zuehre
A new heterocyclic compound, N-(5-benzoyl-2-oxo-4-phenyl-2H-pyrimidin-1-yl)-malonamic acid, was synthesized from N-aminopyrimidine-2-one and malonyldichloride. Bis-chelate complexes of the ligand were prepared from acetate/chloride salts of Cu(II), Co(II), Ni(II), Mn(II), Zn(II), Cd(II), Fe(III), Cr(III), and Ru(III) in methanol. The structures of the ligand and its metal complexes were characterized by microanalyses, IR, NMR, API-ES, UV-Vis spectroscopy, magnetic susceptibility, and conductometric analyses. Octahedral geometry was suggested for all the complexes, in which the metal center coordinates to ONO donors of the ligand. Each ligand binds the metal using C=O, HN, and carboxylate. The cyclic voltammograms of the ligand and the complexes were also discussed. The compounds were evaluated for their antimicrobial activities against Gram-positive and Gram-negative bacteria, and fungi using microdilution procedure. The antimicrobial studies showed that Cu(II), Fe(III), and Ru(III) complexes exhibited good antibacterial activity against Gram-positive bacteria with minimum inhibitory concentrations between 20 and 80 mu g mL-1. However, the ligand and the complexes possess weak efficacy against Gram-negative bacterium and Candida strains. As a result, we suggest that these complexes containing pyrimidine might be a new group of antibacterial agents against Gram-positive bacteria.
Synthesis, Spectroscopic and Biological Studies on the New Symmetric Schiff Base Derived From 2,6-Diformyl With N-Aminopyrimidine
(Elsevier France-editions Scientifiques Medicales Elsevier, 2010) Sonmez, Mehmet; Celebi, Metin; Berber, Ismet
A phenol based novel Schiff base polydentate symmetric ligand was prepared. The complexes were prepared by reacting ligand and the metal chlorides of Cu (II), Ni(II), Co(II) and Fe(II) in methanol to get a series of mononuclear complexes. The complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibility data, IR, UV-Vis, NMR and API-ES mass spectral data. The mononuclear structure of the complexes was confirmed on the basis of elemental analyses, magnetic susceptibility and API-ES mass spectral data. The ligand and all the metal complexes were evaluated for their antimicrobial activity against four Gram-positive bacteria (Staphylococcus aureus ATCC 6538, S. aureus ATCC 25923, Bacillus cereus ATCC 7064 and Micrococcus luteus ATCC 9345), one Gram-negative bacterium (Escherichia coli ATCC 4230), and three yeast (Candida albicans ATCC 14053, Candida krusei ATCC 6258 and Candida parapsilosis ATCC 22019) strains. Therefore, newly synthesized the ligand and two complexes [(Cu(II) and Co(II)] showed good biological activity against all tested bacteria and yeast strains. (C) 2010 Elsevier Masson SAS. All rights reserved.
The Template Synthesis, Spectral Characterization and Thermal Behaviour of New Binuclear Schiff Base Complexes Derived From N-Aminopyrimidine With 2,3-Butandion
(Serbian Chemical Soc, 2007) Sonmez, Mehmet; Sekerci, Memet
Anew series of two types of acyclic binuclear Schiff base complexes, prepared by the template condensation of N-aminopyrimidine and 2,3-butandion in the presence of Cu(II), Ni(II), Co(II) and Zn(II) in n-BuOH solution, were analyzed and characterized by elemental analyses, IR and electronic spectroscopy, conductivity and magnetic measurements. From the conductivity measurements, it is concluded that the complex of Ni-II is a 1: 1 type of electrolyte. All the complexes have sub-normal magnetic moments in accordance with their binuclear nature. The thermal behaviour of the complexes was studied by thermogravimetry.