Synthesis of (S)- and (R)-3-[(benzyloxycarbonyl)oxy]-2,2-difluorotetradecanoic acid
作者:Masao Shiozaki、Yoshiyuki Kobayashi
DOI:10.1016/s0957-4166(00)80289-x
日期:1992.1
Optically active 3-[(benzyloxycarbonyl)oxy]-2,2-difluorotetradecanoic acids, (S)-11 and (R)-22 were synthesized from 3,4,6-tri-O-acetyl-D-glucal and methyl galactopyranoside via 4 and 15, respectively. Reaction of 4 and 15 with octylidene triphenylphosphorane followed by Jones oxidation of the alcohols, treatment with DAST, catalytic hydrogenation of double bond and deprotection of benzyl groups yielded
Is Sulfate Lost During the Chemical Release of Oligosaccharides from Glycoproteins?
作者:Kevin R. King、J. Michael Williams、John R. Clamp、Anthony P. Corfield
DOI:10.1080/07328309608005423
日期:1996.1
Model experiments using methyl alpha-D-galactopyranoside 6-sulfate have implied that the Carlson conditions (1 M sodium borohydride and 0.05 M sodium hydroxide at 45 degrees C) for the release of O-linked oligosaccharides from glycoproteins do not cause significant loss of sulfate ester groups. However the more vigorous conditions used to release N-linked oligosaccharides are more likely to cause considerable sulfate loss from a galactoside 6-sulfate as a result of 3,6-anhydride formation. Experiments with dextran sulfate suggested that sulfate loss due to oxirane formation was also not significant under the Carlson conditions. These results were supported by experiments with [S-35]sulfate-labelled human rectal mucus glycoprotein.
MOCERINO, MAURO;STICK, ROBERT V., AUSTRAL. J. CHEM., 43,(1990) N, C. 1183-1193