Methylated, reduced sialic acids

Kakehi K, Suzuki S, Honda S, et al. 1991. Precolumn labeling of reducing carbohydrates with l-(/ -methoxy)phenyl-3-methyl-5-pyrazolone Analysis of neutral and sialic acid-containing oligosaccharides found in glycoproteins. Anal Biochem 199 256-268. 

Kakehi, K., et al. (1991). Precolumn Labeling of Reducing Carbohydrates with l-(p-methoxy)phenyl-3-methyl-5-pyrazolone Analysis of Neutral and Sialic Acid-containing Oligo Saccharides Found in Glycoproteins, Anal. Biochem. 199 256-268. 

Also attention has been paid to the synthesis of sialodisaccharides, having sialic acid in reducing position. By condensation of tetra-O-acetyl-a-D-glucopyranosyl bromide or tetra-O-acetyl-a-D-galactopyranosyl bromide with methyl 5-acetamido-2,4,7,8-tetra-0-acetyl-3,5-dideoxy-9-0-trityl-D-g/> c ro-D-ga/ac/o-2-nonulopyranosonate in nitromethane under the influence of silver perchlorate, followed by 0-deacetylation, the methyl esters of the corresponding (5(1 9) disaccharides were obtained in 67 and 46% yield, respectively (Khorlin and Privalova 1968). 

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