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    Abstract Unsymmetrical thiourea, which on demand can generate isothiocyanate in the presence of FeCl3, can serve as a latent isothiocyanate functionality and circumvent the difficulties associated with the direct use of reactive isothiocyanate functionality. An unusual and unorthodox reactivity has been achieved during a one-pot reaction of an unsymmetrically di-substituted thiourea with an alcohol in the presence of FeCl3 leading to an expeditious synthesis of O-organyl arylthiocarbamates. In this reaction, a thiono-ester (C‒O) bond is formed at the expense of a thioamidic (C‒N) bond and works over a wide range of structurally diverse thioureas and alcohols without affecting the other functional groups. Keywords: green chemistrythioureaFe-catalystarylthiocarbamateC‒O bond Acknowledgements B.K.P. acknowledges the support of this research from DST New Delhi (SR/S1/OC-79/2009) and CSIR 01(2270)/08/EMR-II. S.K.S. thanks CSIR for fellowships. Thanks are due to Central Instruments Facility (CIF), IIT Guwahati, for NMR and mass spectra and DST-FIST for XRD facility.
    Reactivity
    Phenyl isothiocyanate
    Aroyl isothiocyanate was obtained via the reaction of aroyl chloride with potassium isothiocyanate.Eight thiourea derivatives containing pyridine ring,including N-benzoyl-N'-α-pyridyl thiourea( Ⅲ1),N-p-nitrobenzoyl-N'-α-pyridyl thiourea( Ⅲ2),N-p-chlorobenzoyl-N'-α-pyridyl thiourea( Ⅲ3),N-o-methoxybenzoyl-N'-α-pyridyl thiourea( Ⅲ4),N-benzoyl-N'-β-pyridyl methyl thiourea( Ⅳ1),N-p-nitrobenzoyl-N'-β-pyridylmethyl thiourea( Ⅳ2),N-p-chlorobenzoyl-N'-β-pyridyl methyl thiourea( Ⅳ3) and N-o-methoxybenzoyl-N'-β-pyridylmethyl thiourea( Ⅳ4),were synthesized by addition reaction of aroyl isothiocyanates with 2-amino-pyridine or 3-aminomethyl pyridine,in the yield of 67. 3%,36. 4%,62. 6%,83. 5%,50. 6%,37. 8%,89. 5% and 66.2% respectively. The structures of the products were characterized by1H NMR,IR and elemental analysis. The preliminary biological activity test indicated that the Ⅲ compounds had antibacterial activity against E. coli and had no obvious inhibition activity against B. subtilis. On the contrary,the Ⅳ compounds had antibacterial activity against B. subtilis and had no obvious inhibition activity against E. coli.
    Benzoyl chloride
    Phenyl isothiocyanate
    Citations (0)
    A  series  of  thiourea  derivatives  have  been  synthesized.  Thiourea  derivatives  show  a  broad  spectrum  of  biological  activities  such  as  antibacterial, antiviral, anticancer, anticonvulsion, analgesic  an HDL-elevating. Ethyl isothiocyanate  and  aromatic  amines  were mixed  and  stirred  at  room  temperature  in  acetone  for  15h  to  give  the  corresponding thioureas  in  high  yields.  Their  structures  were  confirmed  by  IR  and  1 H-NMR.  By addition e-donor groups to aromatic amines, thioureas were synthesized in high yields.
    Broad spectrum
    Phenyl isothiocyanate
    A novel and efficient method for synthesis ethoxycarbonyl isothiocyanate and ethoxycarbonyl thioureas catalyzed by TMEDA is reported. A series of N-aryl-N′-ethoxycarbonyl thioureas and arene (or polymethylene)-bis-ethoxycarbonyl thiourea derivatives have been synthesized in good-to-excellent yields via this method at room temperature.
    Citations (2)
    Eight new N aroyl N carboxyl substituted thiourea derivatives have been synthesized by the reaction of aroyl isothiocyanate with various amino acids.Their structures are confirmed by IR, 1H NMR and elementary analysis,and their synthetic conditions are experimentally investigated.
    Proton NMR
    Phenyl isothiocyanate
    Citations (0)
    2‐Amino 3‐substituted‐quinazolin‐4(3H)‐one derivatives were synthesized from Pbf‐isothiocyanate and methyl anthranilate. The construction of the guanidine‐containing quinazolinone heterocyclic skeleton was achieved using Pbf‐activated thiourea treated with primary amines via iodine‐mediated guanidinylation. The desired compounds were obtained after Pbf cleavage by trifluoroacetic acid.
    Quinazolinone
    Trifluoroacetic acid
    Guanidine
    Phenyl isothiocyanate
    Trifluoroacetic anhydride
    Cleavage (geology)
    Citations (9)
    A series of symmetrical 1,3-bis thiourea 1a–e and 1,4-bis thiourea derivatives 2a–e have been successfully synthesized from the reactions of amines with 3-acetylbenzoyl isothiocyanate and 4-acetylbenzoyl isothiocyanate, respectively. All the synthesized compounds were characterized by FT-IR spectroscopy and 1H and 13C NMR spectroscopy. The compounds were screened for their antibacterial activity by turbidimetric method using gram-negative bacteria (E. coli ATCC 8739) using turbidimetric method. The newly synthesized bis-thiourea derivatives bearing aryl side chains showed good antibacterial activity against E. coli. The effect of the molecular structure of the synthesized compounds on the antibacterial activity is discussed.
    Phenyl isothiocyanate
    Aim To synthesize a new series of N-(substituted)benzoyl-N′-substituted pyrimidinyl thiourea derivatives and to evaluate their inhibitory activities against vascular smooth muscle cells proliferation.Methods The subject compounds could be obtained by direct amination of(substituted)benzoyl isothiocyanate with 2-amino-5-bromo-4-substituted pyrimidine derivatives.The inhibitory effect of the target compounds on VSMC proliferation was investigated by MTT.Results and conclusion Ten target new compounds were first synthesized and verified by 1H-NMR and MS.Compound 6b,6c,6g and 6j exhibited moderate inhibitory activities against vascular smooth muscle cells proliferation.
    MTT assay
    Citations (0)
    A small library of novel 1-aroyl-3-(4-aminosulfonylphenyl)thiourea derivatives was synthesized by the reaction of sulfanilamide with substituted aroyl isothiocyanates in dry acetonitrile. The scope of the reaction was indicated by the synthesis of 1-undecanoyl-3-(4-aminosulfonylphenyl)thiourea, an acyl derivative involving alkanoyl isothiocyanate. All the compounds have been characterized by analytical and spectroscopic methods and in one case by single-crystal X-ray diffraction data.
    Sulfanilamide
    Derivative (finance)
    Phenyl isothiocyanate
    Abstract Nitroepoxides were introduced as efficient substrates for the one-pot three-component synthesis of 2-iminothiazoles under catalyst-free conditions. Reaction of amines, isothiocyanates, and nitroepoxides in THF at 10–15 °C afforded corresponding 2-iminothiazoles in high to excellent yields. The reaction proceeds via the in situ formation of thiourea from an amine and an isothiocyanate, followed by nitroepoxide ring opening with the sulfur of thiourea, cyclization reaction, and dehydration cascade. The structures of products were confirmed by IR, NMR, HRMS analyses and X-ray crystallography.
    Reaction conditions