Glucosyl phosphate

Since D-fructose and D-glucose phosphates are amongst the first products of photosynthesis, and since starch (in plants) and glycogen (in animals) are converted by phosphorylase to D-glucosyl phosphate, biosynthesis of carbohydrates revolves around these ubiquitous compounds... 

As evidence for reaction (1), 1 mole of D-glucosyl phosphate was formed per mole of UDP-glucose and D-galactosyl phosphate consumed when the last two compounds were incubated with an extract of Saccharomyces fragilis.13,w Experiments188 with C14-labeled D-glucosyl phosphate also favor the mechanism represented by reactions (1) and (2). 

Using a similar reaction sequence P-(l—>4)-glucosidic linkages were very effectively installed on the support using 4-O-TBS-protected glucosyl phosphate donor 59. Thus, repetitive glycosylation and deprotection furnished trisaccharide 62 in 53% overall yield from 54 after cleavage from the resin (Scheme 6.11). 

The structure of an unusual compound isolated from spores of Ustilago avenue46 has not yet been completely clarified. According to data available,189 it seems to be a cytidine 5 -(D-glucosyl phosphate) derivative having a peptide chain attached to a hydroxyl group of the D-ribose residue. 

The 2-amino-2-deoxy-D-glucosyl phosphate linkage is very labile to acid consequently, the teichoic acid is hydrolyzed under mild conditions to a fragment which is apparently44 (43) or (44). Study of this compound should establish which hydroxyl group of the 2-acetamido-2- deoxy-D-glucose residue bears the phosphodiester group. The alanine ester residues (84a) Unpublished work of the authors with Mr. D. Button. 

D-Glucose may be initially phosphorylated by a hexokinase, followed by transformation into a-D-glucosyl phosphate, which is then enzymically converted, in the presence of UTP, into UDP-D-glucose. On the other hand, D-glucose may be converted into UDP-D-galac-... 

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