• Title/Summary/Keyword: Carbodiimides

Search Result 4, Processing Time 0.019 seconds

Modification of Carboxyl Residues of Proteins with Pyridoxamine as a Fluorophore

  • Kwon, Oh-Shin
    • BMB Reports
    • /
    • v.29 no.3
    • /
    • pp.215-220
    • /
    • 1996
  • A general procedure to quantitate the reaction of carbodiimides with carboxy groups of proteins is described. Pyridoxamine reacts with the o-acylisourea intermediate generated during the reaction of carboxyl residues with carbodiimides. The extent of the reaction is determined by measuring the spectroscopic properties, absorption and emission, of pyridoxyl residues covalently attached to the proteins. Resolved pig brain aspartate aminotransferase (apoenzyme), inactivated by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide, reacts with $[^{3}H]pyridoxamine$. After trypsin digestion, one peptide labeled with radioactive pyridoxyl was separated by reverse phase HPLC.

  • PDF

Heterocyclization Reaction of 4-(2-Methylaziridin-1-yl)-3-ureidobenzotrifluorides under Appel's Conditions

  • Cho, Hyun-In;Lee, Kee-Jung
    • Bulletin of the Korean Chemical Society
    • /
    • v.24 no.2
    • /
    • pp.189-192
    • /
    • 2003
  • The reaction of 4-(2-methylaziridin-1-yl)-3-ureidobenzotrifluorides 4 with triphenylphosphine, carbon tetrachloride, and triethylamine (Appel's condition) led to the corresponding carbodiimides 5, which underwent intramolecular cycloaddition reaction with aziridine under the reaction condition to give the benzimidazolefused heterocycles, 2,3-dihydro-1H-imidazo[1,2-a]benzimidazoles 8 and 12,13-dihydro-5H-benzimidazo[2,3-b] [1,3]benzodiazepines 9.

Synthesis of Phospholene Oxide Catalysts for Hydrolysis Stabilizers (가수분해 방지제 제조용 Phospholene Oxide 촉매의 합성)

  • Lee, Jin-Ha;Lee, Chang-Young
    • Applied Chemistry for Engineering
    • /
    • v.26 no.1
    • /
    • pp.86-91
    • /
    • 2015
  • The MPPO (3-methyl-1-phenyl-2-phospholene-1-oxide) was prepared by using various polymerization inhibitors such as BHT (2,6-di-tert-butyl-4-methylphenol), TBC (4-tert-butylcatechol), and copper stearate. The MPPO was confirmed by the analysis using FTIR, $^1H$-NMR, and GC/MS regardless of the type of inhibitors. The yield of MPPO increased with the increase of reaction time, whereas the purity of MPPO decreased slightly. The yield and purity of MPPO increased with temperature, but the MPPO prepared by using copper stearate as a polymerization inhibitor exhibited no changes in the purity. The amount of inhibitors had no effect on the yield of MPPO. The purity of MPPOs increased with the amount of inhibitors, but the MPPO prepared by using BHT showed no changes of the purity. We found that the MPPO prepared by using copper stearate exhibited the highest catalytic activity for diphenylcarbodiimide synthesis.