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51.
Yazici A Unüş N Altindal A Salih B Bekaroğlu O 《Dalton transactions (Cambridge, England : 2003)》2012,41(13):3773-3779
Compound 1 has been prepared by the reaction of 4-nitrophthalonitrile and trans-2-methoxy-4-(2-nitrovinil)phenol by the common method of nucleophilic substitution of an activated nitro group in an aromatic ring. The metallophthalocyanines 2, 3 were prepared by the reaction of a dinitrile derivative with Co(OAc)(2) or Zn(OAc)(2) in DMSO. The lutetium bis-(phthalocyaninato) complex 4 was obtained by treating the dinitrile derivative with lutetium acetate and DBU in 1-hexanol. The new compounds were characterized by elemental analyses, FT-IR, (1)H-NMR, MALDI-TOF MS and UV/Vis spectral data. The spectroscopic data of the new compounds were in accordance with the structures. The temperature and frequency dependence of dielectric and conduction properties of the spin coated film of compounds (2-4) have been studied by fabricating metal-Pc-metal structures. The results show that compound 2 has giant dielectric constant. At a low range of frequency and room temperature, ε' is found to be equal to 2.33 × 10(6), 1.53 × 10(4) and 1.03 × 10(4) for 2, 3 and 4, respectively. The giant dielectric behavior of 2 is mainly attributed to Maxwell-Wagner polarization. The obtained results also indicated that the frequency dependence of the dielectric permittivity, ε'(ω), exhibits non-Debye type relaxation for all temperatures investigated. The ac conductivity results gave a temperature dependent frequency exponent s. The results were compared with the prediction of the Quantum Mechanical Tunneling and Correlated Barrier Hopping models. 相似文献
52.
Ru(II) complexes of the general formula [RuCl2(′′)(L)] (1: ′N = Nb, L = MeOH; 2: ′N = Nb, L = CH3CN; 3: ′N = Nd, L = CH3CN; 4: ′N = Np, L = CH3CN), [Ru(p‐cymene)(a–b)Cl]Cl (5a: N Na = 2,2′‐bipyridine; 5b: N Nb = 4,4′‐dimethyl–2,2′‐bipyridine), [Ru(′′)(a–b)Cl]Cl (6a: ′N = Nb, a = 2,2′‐bipyridine; 6b: ′N = Nb, b = 4,4′‐dimethyl‐2,2′‐bipyridine; 7a: ′N = Nd, a = 2,2′‐bipyridine; 7b: ′N = Nd, b = 4,4′‐dimethyl‐2,2′‐bipyridine; 8a: ′N = Np, a = 2,2′‐bipyridine; 8b: ′N = Np, b = 4,4′‐dimethyl‐2,2′‐bipyridine) and [Ru(′′)(a)Cl]BF4 (9a: ′N = Nb; a = 2,2′‐bipyridine) were synthesized from the corresponding [RuCl2(p‐cymene)]2 dimer, ′′ and a–b ligands. The compounds were characterized by elemental analysis, IR and NMR. Complex 9a was studied by X‐ray diffraction, confirming its cationic‐mononuclear [RuCl(bb)(a)]+ nature. The synthesized Ru(II) complexes (1–8) were employed as catalysts for the transfer hydrogenation of ketones to secondary alcohols in the presence of KOH using 2‐propanol as a hydrogen source at 82°C. The rates of the transfer hydrogenation reactions strongly depended on the type of and ancillary ligands. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
53.
Mahmut Erzengin Ismet Basaran Umit Cakir Aynur Aybey Selma Sinan 《Applied biochemistry and biotechnology》2012,168(6):1540-1548
Human serum paraoxonase 1 (PON1; EC 3.1.8.1) is a high-density lipoprotein associated, calcium-dependent enzyme that hydrolyses aromatic esters, organophosphates and lactones and can protect the low-density lipoprotein against oxidation. In this study, in vitro inhibition effect of some dihydroxy coumarin compounds namely 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (A), 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (B) and 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (C) on purified PON1 were investigated by using paraoxon as a substrate. PON1 was purified using two-step procedures, namely ammonium sulphate precipitation and Sepharose-4B-l-tyrosine-1-naphthylamine hydrophobic interaction chromatography. The purified enzyme had a specific activity of 11.76?U/mg. The dihydroxy coumarin derivatives of A and B compounds inhibited PON1 enzyme activity in a noncompetitive inhibition manner with K i of 0.0080?±?0.256 and 0.0003?±?0.018?mM values, respectively. C compound exerted an uncompetitive inhibition of PON1 enzyme activity with K i of 0.0010?±?0.173?mM. Moreover, dihydroxy coumarin derivatives of A, B and C compounds were effective inhibitors on purified human serum PON1 activity with IC50 of 0.012, 0.022 and 0.003?mM values, respectively. IC50 value of unsubstituted 6,7 dihydroxy coumarin was found as 0.178?mM. The present study has demonstrated that PON1 activity is very highly sensitive to studied coumarin derivatives. 相似文献
54.
Rasim Dermez S. Abdel Khalek Kemal Kara Bekir Deveci G. N. Günayd?n 《Journal of Russian Laser Research》2012,33(1):42-51
Our aim is to investigate the entanglement dynamics and quantum correlations of a full-trapped ion interacting with two time-independent
laser beams in view of the Lamb–Dicke parameter. For this purpose, the three probability amplitudes in the trapped ion is
taken as ?{1