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    Waste-Free thiolysis of epoxide in water with high yield

    , Article Journal of the Iranian Chemical Society ; Volume 6, Issue 1 , 2009 , Pages 165-167 ; 1735207X (ISSN) Azizi, N ; Akbari, E ; Saidi, M. R ; Sharif University of Technology
    Iranian Chemical Society  2009
    Abstract
    An environmentally benign and efficient process for the preparation of β-hydroxysulfides was developed by a practical and simple reaction of thiols with epoxides in water catalyzed by K2CO3 in high yields and short reaction times  

    Transition metal-free addition of dithiocarbamates to alkynes: One-pot regioselective synthesis of S-vinyl dithiocarbamates under solvent-free conditions

    , Article Monatshefte fur Chemie ; Vol. 145, issue. 3 , 2014 , pp. 521-526 ; ISSN: 00269247 Aryanasab, F ; Saidi, M. R ; Sharif University of Technology
    Abstract
    A convenient, green, and efficient procedure for the synthesis of S-vinyl dithiocarbamates by a simple one-pot three-component condensation of an amine, carbon disulfide, and alkynes is described in the absence of any transition metal catalyst and under solvent-free conditions. This clean and improved method selectively furnishes the corresponding (Z)-S-vinyl dithiocarbamates in good to excellent yields. The reaction is clean with simple product workup and is carried out at 80 C. Graphical Abstract: [Figure not available: see fulltext.]  

    Utility of N-bromosuccinimide-water combination as a green reagent for synthesis of N,S-heterocycles and dithiocarbamates from styrenes

    , Article Synlett ; Volume 31, Issue 18 , August , 2020 , Pages 1823-1827 Matloubi Moghaddam, F ; Goudarzi, M ; Sharif University of Technology
    Georg Thieme Verlag  2020
    Abstract
    An efficient and unprecedented green protocol has been developed for the synthesis of N,S-heterocycles from styrenes and alkyl dithiocarbamates with high to excellent yields. The reaction of primary or secondary amines, CS 2, and styrenes was carried out in water in the presence of a catalytic amount of an inorganic base. All products were made by using an N -bromosuccinimide-H 2O combination as a green and inexpensive reagent. © 2020 American Institute of Physics Inc.. All rights reserved  

    Green carbon-based nanocomposite biomaterials through the lens of microscopes

    , Article Emergent Materials ; 2021 ; 25225731 (ISSN) Rabiee, N ; Ahmadi, S ; Rabiee, M ; Bagherzadeh, M ; Vahabi, H ; Jouyandeh, M ; Saeb, M. R ; Sharif University of Technology
    Springer Nature  2021
    Abstract
    In this work, a green synthesis method was designed and practiced to develop bioactive and biocompatible carbon-based nanocomposites biomaterials. ZnO nanoparticles were synthesized in assistance of leaf extracts and added to a composite nanostructure composed of the reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNT). The resulting green nanocomposite revealed ability to make π-π interactions, hydrogen bonding, and van der Waals interactions with the doxorubicin (DOX). Then, the surface morphology of the synthesized nanocomposite was investigated, and the interrelationship between the surface morphology, relative cell viability, and drug uptake and release behavior were... 

    Colloidal gold nanoparticles: an unexpected catalytic activity in aqueous phase with dioxygen

    , Article catalysis letters ; Volume 144, Issue 7 , July , 2014 , pp. 1219-1222 ; 1572-879X Salari, H. (Hadi) ; Robatjazi, H. (Hossein) ; Hormozi-Nezhad, M. (Mohammad Reza) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Abstract
    Selective oxidations of alkenes were investigated using molecular oxygen in aqueous solution under mild conditions. Colloidal gold nanoparticles are particularly versatile catalysts for oxidation reaction with exceptionally high efficiency and significant selectivity. Gold nanorods (Au NRs) exhibited a slightly enhanced activity compare to gold nanospheres  

    A sustainable approach to the Ugi reaction in deep eutectic solvent

    , Article Comptes Rendus Chimie ; Volume 16, Issue 12 , 2013 , Pages 1098-1102 ; 16310748 (ISSN) Azizi, N ; Dezfooli, S ; Hashemi, M. M ; Sharif University of Technology
    2013
    Abstract
    The Ugi reaction goes fast with high yields in a recyclable and biodegradable low-melting mixture of choline chloride and urea (DES) as a novel and efficient reaction medium. The DES is applicable to a wide range of aldehydes, amines, isocyanides, and acids in good to excellent isolated yields (60-92%) and short reaction times (2-5 h) and can be reused four times without any loss of activity  

    Simple and highly efficient catalyst- and waste-free ring opening of epoxides with Na2S in water

    , Article Monatshefte fur Chemie ; Volume 141, Issue 3 , 2010 , Pages 323-326 ; 00269247 (ISSN) Azizi, N ; Akbari, E ; Ebrahimi, F ; Saidi, M. R ; Sharif University of Technology
    2010
    Abstract
    Water was found to be a highly efficient and green catalyst and solvent for ring-opening reaction of epoxides with Na2S at room temperature to give substituted bis(hydroxyethyl)thioethers in high yields  

    Wettability alteration properties of fluorinated silica nanoparticles in liquid-loaded pores: An atomistic simulation

    , Article Applied Surface Science ; Volume 371 , 2016 , Pages 349-359 ; 01694332 (ISSN) Sepehrinia, K ; Mohammadi, A ; Sharif University of Technology
    Elsevier  2016
    Abstract
    Control over the wettability of reservoir rocks is of crucial importance for enhancing oil and gas recovery. In order to develop chemicals for controlling the wettability of reservoir rocks, we present a study of functionalized silica nanoparticles as candidates for wettability alteration and improved gas recovery applications. In this paper, properties of fluorinated silica nanoparticles were investigated in water or decane-loaded pores of mineral silica using molecular dynamics simulation. Trifluoromethyl groups as water and oil repellents were placed on the nanoparticles. Simulating a pore in the presence of trapped water or decane molecules leads to liquid bridging for both of the... 

    A non-cyanide route for glutaric acid synthesis from oxidation of cyclopentene in the ionic liquid media

    , Article Process Safety and Environmental Protection ; Volume 100 , 2016 , Pages 203-207 ; 09575820 (ISSN) Vafaeezadeh, M ; Hashemi, M. M ; Sharif University of Technology
    Institution of Chemical Engineers 
    Abstract
    The current work deals with the catalytic application of bis(1-butyl-3-methylimidazolium) tungstate ([BMIm]2WO4) for green synthesize of glutaric acid (GA) through oxidative cleavage of cyclopentene. In this method, 30% hydrogen peroxide (H2O2) was used as oxidant with water as the sole by-product of the reaction. Compared to the current synthetic procedures, this protocol is significantly improved in the environmental point of view. Moreover, the effect of the various parameters was investigated on the reaction efficiency. It was found that high yield of GA could obtain without using special methodologies or precautions. The catalytic system is reusable for several times  

    Increase in the β-sheet character of an amyloidogenic peptide upon adsorption onto gold and silver surfaces

    , Article ChemPhysChem ; Volume 18, Issue 5 , 2017 , Pages 526-536 ; 14394235 (ISSN) Soltani, N ; Gholami, M. R ; Sharif University of Technology
    Wiley-VCH Verlag  2017
    Abstract
    Fibrillation of amyloid beta (Aβ) peptide is the hallmark of Alzheimer's disease. Given that interactions at the bio–nano interface affect the fibrillation tendency of this peptide, an understanding of the interactions at Aβ peptide–inorganic surfaces on the microscopic level can help to determine the possible neurotoxicity of nanoparticles. Here, the interactions between a fibril-forming peptide, Aβ25–35, and (111) and (100) facets of gold and silver surfaces have been studied by conducting atomistic molecular dynamics simulations. The obtained results indicate that the adsorption onto gold and silver surfaces force the peptide into the β-sheet-rich conformations, which is prone to... 

    Manganese(III) porphyrin anchored onto magnetic nanoparticles via “Click” reaction: An efficient and reusable catalyst for the heterogeneous oxidation of alkenes and sulfides

    , Article Inorganic Chemistry Communications ; Volume 107 , 2019 ; 13877003 (ISSN) Bagherzadeh, M ; Hosseini, M ; Mortazavi Manesh, A ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    Oxidation of a variety of organic compounds, using Mn-porphyrin, mesotetrakis(4-hydroxyphenyl)porphyrinatomanganese(III), supported onto functionalized silica-coated magnetic nanoparticles via “Click” reaction has been investigated. The heterogeneous catalyst was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR spectroscopy, inductively coupled plasma optical emission spectroscopy (ICP/OES) and energy-dispersive X-ray spectroscopy (EDX). Thermogravimetric analysis (TGA) demonstrated that the prepared catalyst was thermally stable to almost 300 °C, exhibiting high thermostability of the nanocatalyst over a broad range of temperatures. This... 

    Gelatin-based functional films integrated with grapefruit seed extract and TiO2 for active food packaging applications

    , Article Food Hydrocolloids ; Volume 112 , 2021 ; 0268005X (ISSN) Riahi, Z ; Priyadarshi, R ; Rhim, J. W ; Bagheri, R ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Gelatin-based functional films were prepared by the addition of grapefruit seed extract (GSE, 5 wt% based on gelatin) and various amounts of TiO2 (0.5, 1.0, 3.0, and 5.0 wt% based on gelatin). TiO2 was evenly dispersed in the gelatin film, but the film surface roughness was increased as the concentration of TiO2 increased. The mechanical strength and water contact angle (WCA) of the composite film were the highest, while the water vapor permeability (WVP) was the lowest when 0.5 wt% TiO2 was used. The addition of GSE slightly reduced the UV light transmittance, but the addition of TiO2 almost completely prevented the UV light transmission. The addition of GSE and TiO2 did not significantly... 

    Corrosion inhibition of a novel antihistamine-based compound for mild steel in hydrochloric acid solution: experimental and computational studies

    , Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) Ghaderi, M ; Ahmad Ramazani, S. A ; Kordzadeh, A ; Mahdavian, M ; Alibakhshi, E ; Ghaderi, A ; Sharif University of Technology
    Nature Research  2022
    Abstract
    Focused on the assessment of the diphenhydramine hydrochloride (DPH) capabilities as an alternative to conventional and harmful industrial corrosion inhibitors, electrochemical techniques were employed. The optimum concentration of 1000 ppm was determined by molecular simulation and validated through electrochemical experiments. The results acquired from the electrochemical impedance spectroscopy (EIS) study showed that DPH at a concentration of 1000 ppm has a corrosion efficiency of 91.43% after 6 h immersion. The DPH molecules' orientation on the surface was assessed based on EIS predicting horizontal adsorption on the surface. Molecular simulations were done to explore the adsorption... 

    New pyridinium-based ionic liquid as an excellent solvent-catalyst system for the one-pot three-component synthesis of 2,3-disubstituted quinolines

    , Article ACS Combinatorial Science ; Vol. 16, Issue. 3 , 2014 , Pages 93-100 ; ISSN: 21568952 Anvar, S ; Mohammadpoor-Baltork, I ; Tangestaninejad, S ; Moghadam, M ; Mirkhani, V ; Khosropour, A. R ; Landarani Isfahani, A ; Kia, R ; Sharif University of Technology
    Abstract
    The synthesis of a variety of 2,3-disubstituted quinolines has been achieved successfully via a one-pot three-component reaction of arylamines, arylaldehydes and aliphatic aldehydes in the presence of butylpyridinium tetrachloroindate(III), [bpy][InCl4], ionic liquid as a green catalyst and solvent. Mild conditions with excellent conversions, and simple product isolation procedure are noteworthy advantages of this method. The recyclability of the ionic liquid makes this protocol environmentally benign  

    A new geochemical reactive transport model for sandstone acidizing

    , Article Computers and Geosciences ; Volume 166 , 2022 ; 00983004 (ISSN) Khojastehmehr, M ; Bazargan, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Understanding the chemistry of sandstone acidizing is important in designing an effective treatment for subsurface rock formations. The complex chemistry of sandstone systems leads to the precipitation of minerals that contribute to formation damage. Thus, monitoring the concentration and location of precipitates is necessary. In this work, a continuum-scale sequential implicit LEA/PLEA reactive transport model is developed and programmed through coupling OpenFOAM and Reaktoro to improve the model prediction. The proposed LEA/PLEA models are compared for core acidizing simulations at relatively high and low Damköhler numbers. We found that the common assumption of kinetically-controlled flow... 

    Design and Synthesis of Novel Coumarin Derivatives as Quorum Sensing Inhibitors & Performing Click Chemistry Involving Lysozyme Protein and a Novel Synthetic Fluorecent Compound

    , M.Sc. Thesis Sharif University of Technology Mansoori, Sirwan (Author) ; Kalhor, Hamid Reza (Supervisor)
    Abstract
    Quorum Sensing is a cell-to-cell communication pr°Cess depending on cell concentration. Communication among bacterial cells °Ccurs through small molecular signals called autoinducers. The consequences of quorum sensing include the activation of pathogenic properties and activation of the gene for biofilm formation. Biofilms are aggregations of bacteria that adhere to surfaces through extracellular polymeric substances. Bacteria in the biofilm phase are much more resistant to antimicrobial agents than their free-swimming counterparts (i.e. the bacteria in planktonic form). In this study, first a series of coumarin derivatives were synthesized; but due to low solubility of the synthesized... 

    Green Chemistry of Copper Oxide Nanoparticles from Salvia Hispanica: Potential Biological and Catalyst Activity in Click Chemistry

    , M.Sc. Thesis Sharif University of Technology Ghadiri Ghehi, Amir Mohammad (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    The present work was aimed to account a green and eco-friendly synthesis of copper oxide nanoparticles using Salvia hispanica extracts for the first time.The synthesized copper oxide nanoparticles were fully characterized using FT-IR, XRD, FESEM, EDX, TEM and UV-Vis spectroscopy techniques. The average particle size of copper oxide nanoparticles is around 35 nm and shape of nanoparticles are spherical. Biological activity of the synthesized nanoparticles were evaluated in terms of antibacterial assessments against Staphylococcus aureus and Escherichia coli. In the following, the potential antibacterial activity against gram positive (S.aureus) and gram negative (E.coli) bacteria’s were... 

    Investigation of Dithiocarabamates Reaction with α,β-Unsaturated Aldehydes

    , M.Sc. Thesis Sharif University of Technology Ramezani, Meraj (Author) ; Mahmoudi Hashemi, Mohammad (Supervisor) ; Ziyaei Halimehjani, Azim (Supervisor)
    Abstract
    Dithiocarbamates are a group of compounds that nowadays have been used extensively in pharmaceutical agents, organicsynthesis and as fungicides in agriculture.We haveshown, an efficient. regiospecific method for the synthesis of cyclic dithiocarbamates by one-pot three-component cascade reaction of an amine, CS2 and α,β-unsaturated aldehyde via Michael addition/hemiamination reaction in watre under a mild and green procedure with excellent yields and complete regioselectivity