Alaaddin Cukurovali

Cobalt(II), copper(II), nickel(II) and zinc(II) complexes of two novel Schiff base ligands and their antimicrobial activity

Two new, Schiff base ligands containing cyclobutane and thiazole rings, 4-(1-methyl-1-mesitylcyclobutane-3-yl)-2-(2,4-dihydroxybenzylidenehydrazino)thiazole (L1H) and 4-(1-methyl-1-mesitycyclobutane-3-yl)-2-(2-hydroxy-3-methoxybenzylidenehydrazino)thiazole (L2H) and their mononuclear complexes with a 1:2 metal-ligand ratio have been prepared with acetate salts of CoII, CuII, NiII and ZnII in EtOH. The structures of the ligands and their complexes have been established by microanalyses, i.r., u.v.–vis., 13C- and 1H-n.m.r. spectra, and by magnetic susceptibility measurements. The complexes are mononuclear. Thermal properties of the ligands and complexes have been studied by t.g.a. and d.s.c. techniques. Antimicrobial activities of the ligands and their complexes have been tested against eight different microorganisms. Some of the complexes and L1H were found to be active against some of the microorganisms studied.

Comparison of the concentration of trace metals (Ni, Zn, Co, Cu and Se), Fe, vitamins A, C and E, and lipid peroxidation in patients with prostate cancer.

Abstract The anticarcinogenic and antioxidant properties of vitamins A, C, E and pro- or antioxidant properties of trace metals have recently attracted increased attention. We examined the levels of antioxidant vitamins (A, C and E), selenium and malondialdehyde (MDA), and trace metals (Fe, Ni, Zn, Co and Cu) in patients with prostate cancer. In total, 41 subjects (21 controls and 20 prostate cancer patients) were included in the study. The levels of trace elements and Fe in whole blood were determined by atomic absorption spectrophotometry. Serum levels of Se were determined using a fluorimetric method, while a HPLC method was used for serum levels of vitamins and MDA. The levels of vitamins A and E were significantly lower and MDA levels were significantly higher (p<0.001) in patients with prostate cancer compared to controls. Serum vitamin C was significantly lower in patients with prostate cancer when compared to controls (p<0.01). Moreover, Se and Zn levels were also significantly lower, and levels of Ni, Co, and Cu were higher (p<0.001) in patients with prostate cancer than in controls. Fe levels were not significantly different in patients compared to controls (p>0.05). Our findings, together with the results of previous animal studies, suggest that the administration of vitamins A, C, and E, and Se and Zn may be beneficial in the prevention and treatment of human prostate cancer.

Synthesis, characterization and antimicrobial activity of the Schiff bases derived from 2,4-disubstituted thiazoles and 3-methoxysalicylaldehyde, and their cobalt(II), copper(II), nickel(II) and zinc(II) complexes

Two new Schiff base ligands containing 2,4–disubstituted thiazoles and cyclobutane rings, 4-(1-methyl-1-phenylcyclobutane-3-yl)-2-(2-hydroxy-3-methoxybenzylidenehydrazino)thiazole (L1H), 4-(1-methyl-1-p-xylylcyclobutane-3-yl)-2-(2-hydroxy-3-methoxybenzylidenehydrazino)thiazole (L2H) and their mononuclear complexes with a 1:2 metal–ligand ratio have been prepared from acetate salts of CoII, CuII, NiII and ZnII in EtOH. The authenticity of the ligands and their complexes have been established by microanalyses, i.r., 13C- and 1H-n.m.r. spectra, and by magnetic susceptibility and conductivity measurements. The complexes are mononuclear. Thermal properties of the ligands and complexes have been studied by t.g.a. and d.s.c. techniques. Antimicrobial activities of the ligands and their complexes have been tested against six different microorganisms; three are yeast and three are bacteria. One of the ligands and many of the complexes were found to be active against some of the microorganisms studied.

Electrical and optical properties of newly synthesized glyoxime complexes

Abstract In this study, the electrical and optical properties of newly prepared Ni(L 1 H 2 ) and Ni(L 2 H 2 ) complexes have been investigated and the results obtained were analyzed. It is seen that these complexes have inorganic semiconductor properties. The activation energies ( E a ) for the complexes were calculated by using Arrhenius plots and their optical band gaps have been determined through the optical spectra. Thermal probe measurements indicated that these samples have n -type of electrical conductivity.

Solid state electrical conductivity properties of copper complexes of novel oxime compounds containing oxolane ring

Abstract In this study, a novel dioxime having the 1,3-oxolane group, 1,2-dihydroxyimino-3,7-diaza-9,10-O-cyclohexylidenedecane (L1H2) and 9,10,bis(hydroxyimino)-4-8,11,15-tetraaza-1,2,17,18-O-dibenzaloctadecane (L2H2), were synthesised from 1,2-O-benzal-4-aza-7-aminoheptane, which was prepared from a reaction of 1-choloro-2,3-O-benzalpropane and dichlorogloxime. The electrical properties of complexes of those ligands with Cu(II) salts were investigated and obtained results were analyzed. It was seen that these complexes had semiconducting properties. The activation energies (Ea) were calculated for the complexes by using the Arrhenius plot. Thermal probe measurement indicated that these complexes had an n-type electrical conductivity.

Experimental and theoretical investigation of the molecular and electronic structure of 5-(4-aminophenyl)-4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine

The title molecule, 5-(4-aminophenyl)-4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine (C20H21N3S), was prepared and characterized by 1H-NMR, 13C-NMR, IR and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a = 9.4350(5) Å, b = 11.2796(6) Å, c = 18.4170(8) Å and β = 113.378(3)°. In addition to the molecular geometry from X-ray experiment, the molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO) 1H- and 13C-NMR chemical shift values and atomic charges distribution of the title compound in the ground state have been calculated using the Hartree–Fock (HF) and density functional method (DFT) (B3LYP) with 6-31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from −180° to +180° in steps of 10°. Besides, frontier molecular orbitals (FMO) analysis was performed by the B3LYP/6-31G(d) method.

1-(3-methyl-3-mesityl)-cyclobutyl-2-(5-pyridin-4-yl-2H-[1,2,4]triazol-3-ylsulfanyl)-ethanone: X-ray structure, spectroscopic characterization and DFT studies.

The triazole compound 1-(3-Methyl-3-mesityl)-cyclobutyl-2-(5-pyridin-4-yl-2H-[1,2,4]triazol-3-ylsulfanyl)-ethanone, (C23H26N4OS), was characterized by X-ray single crystal diffraction technique, IR NMR spectroscopy and quantum chemical computational methods as both experimental and theoretically. The compound crystallizes in the monoclinic space group P2(1)/c with Z=4. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d,p) basis set in ground state and compared with the experimental data. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the experimental bands observed. The results of the calculations were applied to simulate spectra of the title compound, which show excellent agreement with observed spectra. Data of the title compound display significant structure correlation and provide the basis for future design of efficient materials having the derivatives of 1,2,4-triazole. From the optimized geometry of the molecule, vibrational frequencies, gauge-independent atomic orbital (GIAO) 1H and 13C NMR chemical shift values, molecular electrostatic potential (MEP) distribution, non-linear optical properties and frontier molecular orbitals (FMOs) of the title compound were performed at B3LYP/6-311G(d,p). On the basis of theoretical vibrational analyses, the thermodynamic properties (standard heat capacities, standard entropies, and standard enthalpy changes) of the title compound at different temperatures have been calculated, revealing the correlations between Cp,m0, Sm0, ΔHm0 and temperatures. The predicted non-linear optical properties of the title compound are much greater than those of urea. Data of the title compound display significant structure-correlation and provide the basis for future design of efficient materials having the derivatives of 1,2,4-triazole.

An experimental and theoretical approach to the molecular structure of 2-(4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl)isoindoline-1,3-dione.

The title compound, 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione (C24H22N2O2S), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a = 19.7799(13) Å, b = 6.7473(4) Å, c = 15.7259(9) Å and β = 103.416(5)°. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31G(d), 6–31 + G(d,p) and LANL2DZ basis sets, and compared with the experimental data. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from −180° to +180° in steps of 5°. Besides, molecular electrostatic potential, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were investigated by theoretical calculations.

Spectrophotometric Determination of Nitrite in Water Samples with 4‐(1‐Methyl‐1‐Mesitylcyclobutane‐3‐yl)‐2‐Aminothiazole

Abstract A simple, sensitive, and specific spectrophotometric method for the measurement of nitrite in water has been developed and optimum reaction conditions along with other analytical parameters have been evaluated. The azo dye, 4‐(1‐methyl‐1‐mesitylcylobutane‐3‐yl)‐2‐(p‐N,N‐dimethylazobenzene)‐1,3‐thiazole was synthesized with the reaction of 4‐(1‐methyl‐1‐mesitylcylobutane‐3‐yl)‐2‐aminothiazole and N,N‐dimethyl aniline in acidic medium. Obtained azo dye has been characterized by infrared (IR), 1H nuclear magnetic resonance (NMR), and microanalysis methods. The dye shows an absorption maximum at 482 nm. The method is optimized for acid concentration, pH, amount of reagents required, time, and interfering species. All the determinations were carried out at this wavelength throughout the work. At an analytical wavelength of 482 nm, Beers law is obeyed over the concentration range 0.05 to 2.00 µg nitrite per mL analyte. The molar absorptivity, Sandells sensitivity, and relative standard deviation are 2.03×104 L mol−1 cm−1±251.3 (95%), 2.28×10−3 µg cm−2, and 2.74% (n=10), respectively. The detection limit of the method is 0.012 µg ml−1 of nitrite ion. The method was succesfully applied to the determination of nitrite in tap water and lake water.

Synthesis, Reactivity and Biological Activity of Novel Bisbenzofuran-2-yl-Methanone Derivatives

Preparation of bisbenzofuran-2-yl-methanone (1), the corresponding ketoxime 4, semicarbazone and thiosemicarbazone 3a and 3b, ether derivatives of the ketoximes 5a-j and the alcohol 2 are described. These substances have been prepared in excellent yields. All the synthesized compounds except 5i have been tested against five different microorganisms and some of them were found to be active against some of the species studied.