Lactosyl fluoride

C12H21FO10 a-Lactosyl fluoride [ali 83.2° in water Heptaacetylfluorolactose + Na in CHjOH 150... 

Hepta-O-acetyl-a-lactosyl bromide and iodide are conveniently prepared by treating octa-0-acetyl-/3-lactose with hydrogen bromide and hydrogen iodide, respectively, in glacial acetic acid. The fluoride, prepared by treating the octaacetate with hydrogen fluoride, was found to be appreciably less susceptible to dehalogenation than the other halides saponification with sodium methoxide in methanol produces a-lactosyl fluoride. 

Glycosynthase activity for tetrasaccharide synthesis from a-lactosyl fluoride and p-nitrophenyl /3-cellobioside (PNPC) was measured for the Humicola insolens Cel7B variants in sodium phosphate buffer, pH 7.0, at room temperature. Specific activities were determined by measuring the fluoride ion release rate by a fluoride ion selective electrode. The protein purification yields are the yield of purified protein as determined by western analysis from total cell culture. 

Shoda, S., Kawasaki, T., Obata, K., Kobayashi, S., 1993. A facile enzymatic synthesis of cello-ohgosaccharide derivatives using beta-lactosyl fluoride. Carbohydrate Research 249, 127-137. 

By use of cellulase, P-D-lactosyl fluoride has been condensed with methyl-P-D-cellobioside and thereby a galactosyl glucotriose derivative was made. From this the galactose was enzymically cleaved and methyl P-cellotrioside resulted. Repetition of these two steps provided a route to methyl p-D-cellotetraoside. ... 

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