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    Highly efficient and catalyst-free synthesis of unsymmetrical thioureas under solvent-free conditions

    , Article Tetrahedron Letters ; Volume 50, Issue 1 , 2009 , Pages 32-34 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Pourshojaei, Y ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    A highly efficient and simple synthesis of unsymmetrical thioureas is reported based on the reaction of readily synthesized dithiocarbamates with amines, without using any catalyst under solvent-free conditions. The short reaction time, high yields, and solvent-free conditions are advantages of this method. We did not observe the formation of any symmetric disubstituted thiourea, under these reaction conditions. © 2008 Elsevier Ltd. All rights reserved  

    Highly regioselective, base-catalyzed, biginelli-type reaction of aldehyde, phenylacetone and urea/thiourea kinetic vs. thermodynamic control

    , Article Journal of Sulfur Chemistry ; 2017 , Pages 1-13 ; 17415993 (ISSN) Nematpour, M ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
    Abstract
    An efficient one-pot regioselective synthesis of various novel 3,4-dihydropyrimidin-2(1H)-one (DHPMs) via a three-component Biginelli-type condensation of aldehyde, phenylacetone and urea/thiourea under two different based-catalyzed conditions is described. In kinetic control path, lithium N, N-diisopropylamide (LDA-20 mol % generated in situ from n-BuLi and diisopropylamine) was used as the base, in tetrahydroforane (THF) as the solvent at 0°C. Thermodynamic control path was run with NaH as the base, in EtOH as the solvent under reflux status. The simple procedure, mild base-catalytic reaction conditions, no column chromatography and good to high yields are important features of this... 

    Highly regioselective, base-catalyzed, biginelli-type reaction of aldehyde, phenylacetone and urea/thiourea kinetic vs. thermodynamic control

    , Article Journal of Sulfur Chemistry ; Volume 39, Issue 2 , 2018 , Pages 151-163 ; 17415993 (ISSN) Nematpour, M ; Rezaee, E ; Jahani, M ; Tabatabai, A ; Sharif University of Technology
    Taylor and Francis Ltd  2018
    Abstract
    An efficient one-pot regioselective synthesis of various novel 3,4-dihydropyrimidin-2(1H)-one (DHPMs) via a three-component Biginelli-type condensation of aldehyde, phenylacetone and urea/thiourea under two different based-catalyzed conditions is described. In kinetic control path, lithium N, N-diisopropylamide (LDA-20 mol % generated in situ from n-BuLi and diisopropylamine) was used as the base, in tetrahydroforane (THF) as the solvent at 0°C. Thermodynamic control path was run with NaH as the base, in EtOH as the solvent under reflux status. The simple procedure, mild base-catalytic reaction conditions, no column chromatography and good to high yields are important features of this... 

    One step synthesis of SnS2-SnO2 nano-heterostructured as an electrode material for supercapacitor applications

    , Article Journal of Alloys and Compounds ; Volume 782 , 2019 , Pages 38-50 ; 09258388 (ISSN) Asen, P ; Haghighi, M ; Shahrokhian, S ; Taghavinia, N ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    SnS2-SnO2 nano-heterostructures are synthesized with two different precursors of thioacetamide (TAA) and thiourea (TU) at various solvent ratios (SR) of ethanol and water by using a facile, economical, scalable, and cost-effective solvothermal method. The obtained products have been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmet–Teller (BET) techniques. It is found that different precursors and various SR values have an influence on the composition and morphologies of the prepared nanostructures, leading to variation in capacitive behavior of the fabricated electrodes.... 

    Monte Carlo sampling and multivariate adaptive regression splines as tools for QSAR modelling of HIV-1 reverse transcriptase inhibitors

    , Article SAR and QSAR in Environmental Research ; Volume 23, Issue 7-8 , Jun , 2012 , Pages 665-682 ; 1062936X (ISSN) Alamdari, R. F ; Mani Varnosfaderani, A ; Asadollahi Baboli, M ; Khalafi Nezhad, A ; Sharif University of Technology
    2012
    Abstract
    The present work focuses on the development of an interpretable quantitative structure-activity relationship (QSAR) model for predicting the anti-HIV activities of 67 thiazolylthiourea derivatives. This set of molecules has been proposed as potent HIV-1 reverse transcriptase inhibitors (RT-INs). The molecules were encoded to a diverse set of molecular descriptors, spanning different physical and chemical properties. Monte Carlo (MC) sampling and multivariate adaptive regression spline (MARS) techniques were used to select the most important descriptors and to predict the activity of the molecules. The most important descriptor was found to be the aspherisity index. The analysis of variance... 

    Nano cobalt ferrite catalyzed coupling reaction of nitroarene and alkyl halide: An odorless and ligand-free rout to unsymmetrical thioether synthesis

    , Article Catalysis Communications ; Volume 94 , 2017 , Pages 33-37 ; 15667367 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Sharif University of Technology
    Elsevier B.V  2017
    Abstract
    This study describes an odorless protocol for the synthesis of unsymmetrical sulfides via cobalt ferrite (CoFe2O4) catalyzed cross-coupling reaction of nitroarenes with alkyl halides in the presence of thiourea as sulfur source under ligand-free conditions. The catalyst was recycled using external magnetic field and reused for ten consecutive runs in the reaction of nitrobenzene, thiourea and benzyl bromide without significant loss of activity. Apart from being magnetically separable, being inexpensive and air-stable are another important features of this catalytic system. All the products were formed in good yields and short reaction times. © 2017 Elsevier B.V  

    Controlling morphology and structure of nanocrystallineVcadmium sulfide (CdS) by tailoring solvothermal processing parameters

    , Article Journal of Nanoparticle Research ; Volume 13, Issue 7 , 2011 , Pages 3011-3018 ; 13880764 (ISSN) Dalvand, P ; Mohammadi, M. R ; Sharif University of Technology
    2011
    Abstract
    Cadmium sulfide (CdS) with different morphologies was successfully prepared by solvothermal process by controlling the processing parameters, including nature of precursor and solvent, reaction temperature and process time. X-ray diffraction patterns revealed that, in all cases highly pure and crystallized CdS with hexagonal structure were obtained. In addition, it was found that the processing parameters influence on preferable growth direction of CdS nanostructures. Field emission scanning electron microscope analysis showed that CdS nanowires with different aspect ratios were obtained (depending upon the reaction temperature and process time) in presence of sulfur powder and... 

    Synthesis of micelles based on chitosan functionalized with gold nanorods as a light sensitive drug delivery vehicle

    , Article International Journal of Biological Macromolecules ; Volume 149 , 2020 , Pages 809-818 Pourjavadi, A ; Bagherifard, M ; Doroudian, M ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    This study aims to design photo-triggered micelles by using a natural base polymer. Chitosan was functionalized with thiourea, and in the next step, it was modified by grafting poly(L-lactide), poly(N-isopropylacrylamide), and poly(acrylamide) in determined ratio to form thermo-sensitive micelles. The sulfur content of chitosan@thiourea was measured about 2%. Grafting of polymers on chitosan was characterized by FT-IR and NMR techniques. The critical micellar concentration was measured by using photo luminescence spectroscopy. The size and surface morphology experiments revealed that average size of micelles is about 14 nm, and the length and width of GNRs are about 65 and 19 nm,...