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11.
Javad Azizian Ali A. Mohammadi Ilyar Bidar Peiman Mirzaei 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):805-808
A simple, efficient, and practical procedure for the Pechmann condensation using KAl(SO4)2 · 12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available catalyst is described under solvent-free condition at
65°C. These improved reaction conditions allow the preparation of a wide variety of some new substituted coumarins in high
yields (86–96%) and purity under mild reaction conditions. Compared to the classical Pechmann condensation, this new method consistently has the advantage of high yields.
Correspondence: Ali A. Mohammadi, Department of Chemistry, Shahid Beheshti University, P.O. Box 19839-4716, Tehran, Iran. 相似文献
12.
Babak Mokhtarani Ali Sharifi Hamid Reza Mortaheb Mojtaba Mirzaei Morteza Mafi Fatemeh Sadeghian 《The Journal of chemical thermodynamics》2009,41(12):1432-1438
Densities and viscosities of 1-butyl-3-methylimidazolium nitrate [Bmim][NO3], and its binaries with alcohol (ethanol, 1-propanol, or 1-butanol) were measured at different temperatures. The densities and viscosities of pure ionic liquid were correlated successfully by empirical equations. The Vogel–Fulcher–Tammann equations can fit the experimental data of viscosities for pure IL. Excess molar volume and viscosity deviations were calculated for the binaries. The excess molar volumes have negative deviations from the ideal solution. 相似文献
13.
A new PVC membrane electrode for the determination of phenylephrine hydrochloride based on the formation of an ionassociation complex of phenylephrine hydrochloride with the phosphotungstate counter anion as an electroactive material dispersed in a PVC matrix is described. The sensor shows a fast, stable, near-Nernstian response for 1.0 × 10?5 to 1.0 × 10?1 M phenylephrine hydrochloride at 25 °C over the pH range of 3.5–8.0 with a cationic slope of 58.1 ± 0.6 mV decade?1. The electrode was successfully used for potentiometric determination of phenylephrine hydrochloride in some pharmaceutical drugs. 相似文献
14.
Mohammad Mahdi Ahari-Mostafavi Ali Sharifi Mojtaba Mirzaei Massoud Amanlou 《Journal of the Iranian Chemical Society》2014,11(4):1113-1119
The objective was to obtain new scaffold of compounds possessing anti-urease activity. For this new and simple method for the synthesis of β-aryl-β-mercapto ketone derivatives based on Michael addition of thiophenol to chalcones in an ionic liquid as a solvent was improved. The products were obtained in good to moderate yields with high purity and characterized by spectral and elemental analyses. The activities of synthesized compounds were investigated as new inhibitors of jack bean urease. Among 22 synthesized compounds, all of them have shown inhibitory effect in micromolar range, and the most potent one has IC50 = 6 μM compared to hydroxyurea IC50 = 100 μM as a reference inhibitor. A docking study was performed using Autodock 4.2 in parallel to in vitro experiments to illustrate the corresponded binding affinities as well as binding site, and involved residues in interaction. These computational results complimented the experimental inhibition activity and enabled us to report a potent urease inhibitors based on β-aryl-β-mercapto ketone scaffold. 相似文献
15.
Preparation of antibody-coated gold nanoparticles (GNPs) specific to aflatoxins B1, B2, G1 and G2 and its use in developing aflatoxins diagnostic method were presented in this paper. The formation of gold-labeled antibodies was accomplished at optimal condition. Due to severe overlapping between the emission profiles for the aflatoxins, they cannot be determined by direct inspection of data. The strategy used in this study, constituted by artificial neural network (ANN), was easy to implement and to originate reliable results. ANN can be successfully applied to spectrofluorimetric spectra matrices to simultaneous determination of total aflatoxins. Quantitative results obtained using ANN method for aflatoxins in pistachio nuts samples were compared to those obtained using the HPLC method. Obtained results using these two methods did not show significant differences. 相似文献
16.
Masoumeh Kouhi Ali Mohebbi Mohammad Mirzaei 《Research on Chemical Intermediates》2013,39(5):2049-2062
In this paper we propose an approach for ranking self-healing polymeric coatings containing micro/nanocapsules in order of corrosion-protection effectiveness on exposure to 3.5 % (w/w) NaCl solution. The results indicated that development of electrochemical cells was inhibited by the active components of the ruptured embedded inhibitor micro/nanocapsules which were released into a scratch inflicted in the polymeric coating on steel surface. Undamaged surface film of test and control specimens exposed to the solution had excellent corrosion-inhibition performance, as reflected by results from both electrochemical impedance spectroscopy and polarization tests. Moreover, three coatings containing capsules synthesized at three different agitation rates with the same thickness were compared to determine the optimum rate. For the optimum rate the optimum thickness was then determined. The areas under Bode plots were determined and used as useful values for evaluation and ranking the coatings. It was found that the area under the Bode plot is a good criterion for evaluating polymeric coating degradation during immersion. There was good agreement between the results of this work and those from electrochemical tests. 相似文献
17.
Catalytic behaviors of Co-Mn/TiO catalysts for Fischer-Tropsch synthesis 《燃料化学学报》2012,40(12):1435-1443
The 15%(Co-Mn)/TiO2,(Co/Mn=1/6) catalyst was prepared using fusion procedure and studied for the conversion of synthesis gas to C2~4 olefins. The effects of calcination conditions and operation conditions such as the H2/CO molar feed ratio at different temperatures, gas hourly space velocity (GHSV) and total reaction pressure on the catalytic performance of catalyst were investigated. The stability of the catalyst during 150 h at optimal operation conditions (t=250 ℃ H2/CO=2/1, GHSV=1 500 h-1 and p=0.3 MPa) has been investigated. It is found that this catalyst is high stable for production C2~4 olefins. Characterizations of both precursors and calcined catalysts by powder X-ray diffraction, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) specific surface area measurement and thermal analysis methods such as thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) show that the different preparation method influences the catalyst precursor structure and morphology. 相似文献
18.
S. Shahraki A. Heidari H. R. Mirzaei M. Saeidifar N. Ahmadinasab H. Mansouri-Torshizi 《Journal of the Iranian Chemical Society》2018,15(3):697-709
A novel 1,1-cyclobutanedicarboxylato-8-hydroxyquinolinatopalladate(II), Na[Pd(8-QO)(cbdca)] (8-QO = 8-hydroxyquinoline and cbdca = 1,1-cyclobutanedicarboxylate) has been designed and synthesized. The structure of the complex has been characterized by elemental analysis, molar conductance, FT-IR, UV–Vis, 13C NMR, 1H NMR spectroscopy. The cytotoxic activities of the complex have been tested against human foreskin fibroblast normal cell line, HFFF2 and two human breast cancer cell lines, T47D and MCF-7 by MTT assay techniques. The binding properties of the antitumor complex with calf thymus DNA (ctDNA) have been investigated under physiological condition in Tris–HCl buffer solution at pH 7.0 by absorption spectroscopy, fluorescence titration spectra, EB displacement and gel chromatography studies. All these results demonstrate that the water soluble complex can cooperatively bind to ctDNA at low concentrations through a static quenching procedure. Thermodynamic parameters were calculated according to Van’t Hoff equation which indicated that hydrogen bond and van der Waals force play predominant roles in the binding process. Finally, the results of molecular docking calculations clarify the binding mode which is in good accordance with experimental results. 相似文献
19.
20.
Molecular Diversity - This study describes the use of 3-aminotriazole, different aldehydes and N-methyl-1-(methylthio)-2-nitroethenamine as a ketene N,S-acetal in a three-component condensation for... 相似文献