Ascorbic acid glucosyl

Glucosyl-fructose, 24 237 D-Glucuronic acid, 4 711 Glucuronic pathway, of ascorbic acid biosynthesis, 25 762-763, 763-764 Glue, kaolin application, 6 688t Glueckauf approximation, adsorption, 1 608, 609... 

These generalizations are illustrated by the recent synthesis of L-ascorbic acid glucosides 11 and 12 (16), The monosodium salt of ascorbic acid in N,N-dimethylformamide (DMF) affords exclusively the 03 monoalkylated derivative 9 on alkylation with 2,3,4,6-tetra-O-a-n-glucopyranosyl bromide. To obtain the 02 glucosylated derivative 10, under the same conditions, required the protection of the C3 hydroxyl as a methyl ether. Several workers have reported the biosynthesis of ascorbic acid glucosides in bacteria (17) however, the structure and position of glucosylation in these compounds has not been unambiguously determined. 

Treatment of the anion of L-ascorbic acid with tetra-O-acetyl-a-o-glucopy-ranosyl bromide led to j8-glucosylation at C-3, and subsequent methylation gave access to compound (17), When these two substitution processes were reversed the 2-j8-D-glucopyranosyl 3-methyl ether (18) was obtained. Conversion of the acid into the 5,6-0-isopropylidene derivative followed by sul-... 

Enzymic transglycosylation, with maltose as glucosyl donor, can be used to make 2-0-a-D-glucopyranosyl-L-ascorbic acid, which may have potential as a storage form of ascorbate in commercial formulations. 3,74 Microorganisms have also been identified which can phosphorylate ascorbic acid specifically at 0-2P ... 

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