109-85-3Relevant articles and documents
Lack of effect of the length of oligoglycine- and oligo(ethylene glycol)-derived para-substituents on the affinity of benzenesulfonamides for carbonic anhydrase II in solution
Jain, Ahamindra,Huang, Shaw G.,Whitesides, George M.
, p. 5057 - 5062 (1994)
Using 1H NMR spectroscopy, values of T2 have been determined for the methylene protons of the oligoglycine moieties of para-substituted benzenesulfonamides having structures H2NO2SC6H4CO(Gly)(n)OH (n = 1-6) bound at the active site of bovine carbonic anhydrase II (CA, EC 4.2.1.1). These values have been correlated with measurements of dissociation constants of these complexes, in order to infer motion of these ligands when bound to the enzyme. Motion of glycines 1-3 (those closest to the aryl ring) is hindered by their proximity to the protein; motion of glycines 4-6 is relatively unhindered. Despite the restriction to motion inferred for glycines 1-3, the values of K(d) for the six compounds (n = 1-6, 1-6) are indistinguishable within experimental uncertainty (± 20%): K(d) in μM (n) 0.30 (1); 0.26 (2); 0.33 (3); 0.37 (4); 0.37 (5); 0.34 (6). There is, therefore, an unexpected compensation of the loss in conformational entropy on binding by another contributor to the free energy.
HYDROLYSIS OF N-SALICYLIDENE-2-METHOXYETHYLAMINE. INTRAMOLECULAR GENERAL BASE CATALYSIS AND SPECIFIC EFFECTS OF BORIC ACID.
Nagamatsu,Okuyama,Fueno
, p. 2502 - 2507 (1984)
Hydrolysis of N-salicylidene-2-methoxyethylamine is kinetically investigated at 30 degree C. Intramolecular general base catalysis by the o-O** minus substituent takes place in the neutral pH region. Nucleophilic catalysis by morpholine was also found to be operative. Added boric acid accelerates the hydrolysis above pH 5. 5 while it decelerates the hydrolysis below pH 5. 5. The hydrolysis rate as the function of the boric acid concentration follows a saturation curve in harmony with a reaction sequence involving a rapid equilibrium formation of a borate-substrate complex followed by its breakdown. The morpholine catalysis is inhibited by boric acid in accord with the slow reaction of morpholine with the complex.
INFLUENCE OF BORIC ACID ON THE HYDROLYSIS RATE OF A HYDROXY SCHIFF BASE.
Matsuda,Nagamatsu,Okuyama,Fueno
, p. 500 - 505 (1984)
Effects of boric acid on the rate of hydrolysis of a Schiff base derived from alpha -hydroxyisobutyrophenone and 2-methoxyethylamine were examined in the pH range 4. 2-10. 4 at 30 degree C. The rate increased above pH 7 but decreased below pH 7 with increasing borate concentration following a saturation curve. This is consistent with a reaction sequence involving a preequilibrium formation of a borate-substrate complex followed by its rate-determining decay to the hydrolysis products. The formation constant of the complex showed a bell-shaped change with pH but the rate constant for the complex decay was constant above pH 7, a small change being observed at lower pH. A mechanism involving an intramolecular transfer of the boron-coordinated hydroxide ion to the imine carbon within the complex is presented.
Preparation method of 2-methoxyethylamine
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Paragraph 0029-0061, (2021/05/08)
The invention relates to a preparation method of 2-methoxyethylamine in the technical field of organic synthesis chemical industry. The preparation method comprises the following steps: dissolving N,N'-bis(2-methoxyethyl)thiourea as an initial raw material in a solvent, and carrying out an oxidation reaction in the presence of an oxidant to prepare 2-methoxyethylamine. The method provided by the invention has the advantages of short route steps, mild conditions and high product yield, and provides a universal new method for preparation of 2-methoxyethylamine.
Synthesis of oxalamides by acceptorless dehydrogenative coupling of ethylene glycol and amines and the reverse hydrogenation catalyzed by ruthenium
Ben-David, Yehoshoa,Diskin-Posner, Yael,Milstein, David,Zhou, Quan-Quan,Zou, You-Quan
, p. 7188 - 7193 (2020/07/23)
A sustainable, new synthesis of oxalamides, by acceptorless dehydrogenative coupling of ethylene glycol with amines, generating H2, homogeneously catalyzed by a ruthenium pincer complex, is presented. The reverse hydrogenation reaction is also accomplished using the same catalyst. A plausible reaction mechanism is proposed based on stoichiometric reactions, NMR studies, X-ray crystallography as well as observation of plausible intermediates.
