29315-88-6Relevant articles and documents
Efficient preparation of β-D-glucosyl and β-D-mannosyl ureas and other N-glucosides in carbohydrate melts
Russ, Carolin,Ilgen, Florian,Reil, Christian,Luff, Claudia,Haji Begli, Alireza,Koenig, Burkhard
experimental part, p. 156 - 161 (2011/03/23)
Sugar melts or solvent-free systems have been used to react simple unprotected hexoses at the C-1 atom with urea and urea derivatives to sugar-ureides by acid catalysis and with short reaction times. In one step, β-d-glucosyl- and β-d-mannosyl urea 2a/b were obtained in high yields. d-Galactose 6, N-acetyl-d-glucosamine 7, l-rhamnose 8 and 2-deoxy-d-glucose 9 were converted likewise to glycosyl ureas. Additionally, urea-related nucleophiles were investigated as melt components. N,N′-Ethylene urea 15, N,N′-allylurea 16 and ethyl carbamate 18 were β-selectively converted with d-glucose in good yield, giving the corresponding N-glycosides. Under these conditions, however, the condensation product with N-octylurea 17 was not accessible.
Assessment of synthetic methods for the preparation of N-β-d-glucopyranosyl-N′-substituted ureas, -thioureas and related compounds
Somsak, Laszlo,Felfoeldi, Nora,Konya, Balint,Huese, Csaba,Telepo, Katalin,Bokor, Eva,Czifrak, Katalin
, p. 2083 - 2093 (2008/12/21)
Preparation of O-peracetylated N-β-d-glucopyranosyl-N′-acyl urea derivatives resulted in the formation of anomeric mixtures under the following conditions: acylation of O-peracetylated β-d-glucopyranosyl urea by acyl chlorides in the presence of ZnCl2 in refluxing CHCl3; addition of O-peracetylated β-d-glucopyranosylamine to acyl isocyanates in acetonitrile at rt; addition of carboxamides to in situ prepared O-peracetylated β-d-glucopyranosyl isocyanate in refluxing toluene. Deprotection of O-peracetylated N-β-d-glucopyranosyl-N′-acyl ureas either under base (NaOMe in MeOH at or below rt) or under acid (KHSO4 or AcCl in MeOH at rt) catalyzed transesterification conditions resulted in unavoidable partial cleavage of the N′-acyl moieties. Reaction of β-d-glucopyranosylammonium carbamate with an isocyanate, isothiocyanate or isoselenocyanate in dry pyridine at rt appears as a general method for the preparation of the corresponding β-d-glucopyranosyl ureas, -thio- and -selenoureas, respectively, inclusive N′-acyl derivatives.
CARBOHYDRATE-UREA-PHENOL-BASED ADHESIVES: TRANSIENT FORMATION OF MONO- AND DI-D-GLUCOSYLUREA
Helm, Richard F.,Karchesy, Joseph J.,Barofsky, Douglas F.
, p. 103 - 112 (2007/10/02)
The chemistry of the acid stage of the synthesis of carbohydrate-based adhesives has been investigated.The sulfuric acid-catalyzed reactions of D-glucose with urea in a phenol-water solution provided both N-β-D-glucopyranosylurea and N,N'-di-β-D-glucopyranosylurea.These compounds have been isolated from the resin as perbenzoylated derivatives, and compared spectroscopically with authentic samples.The D-glucosylureas are transient products whose combined yields approach 35percent of the carbohydrate fraction during the initial stages of resin synthesis.Only traces of 5-(hydroxymethyl)-2-furaldehyde, levulinic acid, and formic acid were detected in the resin mixture, suggesting that the classical dehydration pathway is not a major route for the disappearance of D-glucose.
