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101.
Manouchehr Mamaghani Khalil Tabatabaeian Abed Badrian 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1347-1353
A new, universal, and versatile method has been developed for the synthesis of the chiral α,β-unsaturated N-acyl-oxazolidin-2-ones 4 based on the Wittig reaction of the triphenylphosphonium salt 7 derived from the (R)-3-(2-Chloro-acetyl)-5,5-dimethyl-4-phenyl-oxazolidin-2-one 6. 相似文献
102.
Esenpınar AA Durmuş M Bulut M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(3):608-617
The non-peripherally (np-QZnPc) and peripherally (p-QZnPc) tetrakis-[7-oxo-(3-[(2-diethylaminomethyliodide)ethyl)]-4-methylcoumarin]-phthalocyaninatozinc complexes have been prepared by quaternization of non-peripherally and peripherally tetrakis[7-oxo-(3-[(2-diethylamino)ethyl)]-methylcoumarin] phthalocyaninato zinc complexes with methyliodide in dimethylsulfoxide (DMSO). The new quaternized zinc phthalocyanine complex (np-QZnPc) has been characterized by elemental analysis, MALDI-TOF, IR and UV-vis spectral data. The photophysical and photochemical properties of the peripherally and non-peripherally quaternized tetrakis-3-[(2-diethylamino)ethyl]-7-oxo-4-methylcoumarin substituted zinc phthalocyanines are reported. The effects of the position of the substituents and the aggregation of the phthalocyanine molecules on the photophysical and photochemical properties are also investigated. General trends are described for photodegradation, singlet oxygen and fluorescence quantum yields, and fluorescence lifetimes for complexes np-ZnPc/p-ZnPc in DMSO and for complexes np-QZnPc/p-QZnPc in DMSO, phosphate buffered solution (PBS) and PBS+Triton-X 100 solutions. The fluorescence of the tetra-substituted quaternized zinc phthalocyanine complexes (np-QZnPc/p-QZnPc) are effectively quenched addition of 1,4-benzoquinone (BQ) and this study also presented the ionic zinc phthalocyanine complexes strongly bind to bovine serum albumin (BSA). 相似文献
103.
Esenpınar AA Durmuş M Bulut M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):690-697
The synthesis of novel 6,7-[(12-crown-4)-3-[p-(3,4-dicyanophenoxy)phenyl]coumarin (1), 6,7-[(12-crown-4)-3-[p-(2,3-dicyanophenoxy)phenyl]coumarin (2), and their corresponding tetra-(chromenone 12-crown-4)-substituted zinc (II) phthalocyanine complexes (3 and 4) have been prepared. These new compounds have been characterized by elementel analysis, (1)H NMR (1 and 2), MALDI-TOF, IR and UV-Vis spectral data. The fluorescence intensity changes for 1 and 2 by addition of Na(+) or K(+) ions have been determined at 25°C in THF. Intensity of the binding Na(+)- and K(+)-complexes (1 and 2) have decreased. The effects of the chromenone crown ether on the phthalocyanine molecule concerning photophysical and photochemical properties are also investigated. Photodegredation, singlet oxygen, fluorescence quantum yields, and fluorescence lifetimes of zinc phthalocyanine complexes (3 and 4) are also examined in DMSO. 相似文献
104.
105.
S. Mohammad Reza Seyedein Ghannad Mohammad Nader Lotfollahi Ali Haghighi Asl 《The Journal of chemical thermodynamics》2011,43(3):329-333
Experimental (liquid + liquid) equilibrium (LLE) data for a ternary system containing (ethylene glycol + benzene + cyclohexane) were determined at temperatures (298.15, 308.15, and 318.15) K and at atmospheric pressure. The experimental distribution coefficients and selectivity factors are presented to evaluate the efficiency of the solvent for extraction of benzene from cyclohexane. The effect of temperature in extraction of benzene from the (benzene + cyclohexane) mixture indicated that at lower temperatures the selectivity (S) is higher, but the distribution coefficient (K) is rather lower. The LLE results for the system studied were used to obtain binary interaction parameters in the UNIQUAC and NRTL models by minimizing the root mean square deviations (RMSD) between the experimental results and calculated results. Using the interaction parameters obtained, the phase equilibria in the systems were calculated and plotted. The NRTL model fits the (liquid + liquid) equilibrium data of the mixture studied slightly better. The root mean square deviations (RMSDs) obtained comparing calculated and experimental two-phase compositions are 0.92% for the NRTL model and 0.95% for the UNIQUAC model. 相似文献
106.
Asl? Gök?. ?smail K?rba?lar Hasan Uslu H. Ghanadzadeh Gilani 《Fluid Phase Equilibria》2011,303(1):71-75
Liquid-liquid equilibrium (LLE) data of the solubility (binodal) curves and tie-line end compositions were examined for mixtures of {(water (1) + butyric acid (2) + diethyl succinate or diethyl glutarate or diethyl adipate (3)} at 298.2 K and 101.3 ± 0.7 kPa. The relative mutual solubility of butyric acid is higher in the diethyl succinate or diethyl glutarate or diethyl adipate layers than water layers. The consistency of the experimental tie-lines was determined through the Othmer-Tobias correlation equation. The LLE data were correlated with NRTL model, indicating the reliability of the NRTL equations for these ternary systems. The best results were achieved with the NRTL equation, using non-randomness parameter (α = 0.3) for the correlation. Distribution coefficients and separation factors were measured to evaluate the extracting capability of the solvents. 相似文献
107.
Dr. Cecilia C. Russell Dr. Andrew Stevens Kelly A. Young Jennifer R. Baker Siobhann N. McCluskey Dr. Manouchehr Khazandi Hongfei Pi Dr. Abiodun Ogunniyi Dr. Stephen W. Page Prof. Darren J. Trott Prof. Adam McCluskey 《ChemistryOpen》2019,8(7):896-907
Robenidine (E)-N′-((E)-1-(4-chlorophenyl)ethylidene)-2-(1-(4-chlorophenyl)ethylidene)hydrazine-1-carboximidhydrazide displays methicillin-resistant Staphyoccoccus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) MICs of 2 μg mL−1. Herein we describe the structure-activity relationship development of a novel series of guanidine to 2-aminopyrimidine isosteres that ameliorate the low levels of mammalian cytotoxicity in the lead compound while retaining good antibiotic activity. Removal of the 2-NH2 pyrimidine moiety renders these analogues inactive. Introduction of a central 2-NH2 triazine moiety saw a 10-fold activity reduction. Phenyl to cyclohexyl isosteres were inactive. The 4-BrPh and 4-CH3Ph with MIC values of 2 and 4 μg mL−1, against MRSA and VRE respectively, are promising candidates for future development. 相似文献
108.
Leila Ahmadian‐Alam Vahid Haddadi‐Asl Leila Hatami Hossein Roghani‐Mamaqani Mehdi Salami‐Kalajahi 《国际化学动力学杂志》2012,44(12):789-799
The effect of clay nanolayers and catalyst concentration on the kinetics of atom transfer radical copolymerization of styrene and butyl acrylate initiated by activators generated by electron transfer (AGET initiation system) or an alkyl halide (normal initiation system) was studied. Monomer conversion was studied by attenuated total reflection–Fourier transform infrared spectroscopy, and also proton nuclear magnetic resonance (1H NMR) spectroscopy was utilized to evaluate the heterogeneity in the composition of poly(styrene‐co‐butyl acrylate) chains. A decrease in the copolymerization rate of styrene and butyl acrylate in the presence of clay platelets was observed since clay layers confine the accessibility of monomer and growing radical chains. Considering the linear first‐order kinetics of the polymerization, successful AGET and normal atom transfer radical polymerization (ATRP) in the presence of clay nanolayers were carried out. Consequently, poly(styrene‐co‐butyl acrylate) chains with narrow molecular weight distribution and low polydispersity indices (1.13–1.15) were obtained. The linearity of ln([M]0/[M]) versus time and molecular weight distribution against conversion plots indicates that the proportion of propagating radicals is almost constant during the polymerization, which is the result of insignificant contribution of termination and transfer reactions. Controlled synthesis of poly(styrene‐co‐butyl acrylate)/clay is implemented with the diminishing catalyst concentration of copper(I) bromide/N,N,N′,N′′,N′′‐pentamethyl diethylene triamine without affecting the copolymerization rate of normal ATRP. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 789–799, 2012 相似文献
109.
110.
New predictor-corrector approach for nonlinear fractional differential equations: error analysis and stability
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Mohammad Shahbazi Asl Mohammad Javidi Bashir Ahmad 《Journal of Applied Analysis & Computation》2019,9(4):1527-1557
In this paper, the predictor-corrector approach is used to propose two algorithms for the numerical solution of linear and non-linear fractional differential equations (FDE). The fractional order derivative is taken to be in the sense of Caputo and its properties are used to transform FDE into a Volterra-type integral equation. Simpson''s 3/8 rule is used to develop new numerical schemes to obtain the approximate solution of the integral equation associated with the given FDE. The error and stability analysis for the two methods are presented. The proposed methods are compared with the ones available in the literature. Numerical simulation is performed to demonstrate the validity and applicability of both the proposed techniques. As an application, the problem of dynamics of the new fractional order non-linear chaotic system introduced by Bhalekar and Daftardar-Gejji is investigated by means of the obtained numerical algorithms. 相似文献