Isomaltose support

Scheme 8.—Synthesis of Isomaltose (8) on a Light-sensitive, Solid Support ((P)).

This supports the report of reversal of maltase action. Recently the synthesis of isomaltose, in which the primary hydroxyl of carbon 6, rather than the secondary hydroxyl of carbon 4, forms the glycoside, was reported." The thermodynamic and kinetic factors involved in the formation of various disacoharides of glucose have not yet been evaluated. The a-glucosidotransferases of molds have been studied intensively. They do not form 1-4 linkages, but transfer only to the 6-position of glucose. A series of oligosaccharides is formed from maltose by these enzymes. The... 

Five tetrasaccharides have been isolated from the acetolysis products of the insoluble dextran elaborated by Leuconostoc mesenteroides NRRL B-1299. Structural identification of the oligomers demonstrated that the (1 -> 3>-Hnl ed a-D-glucosyl residues occur in sequences, thus supporting the theory that there is a relationship between lower solubility and sequences of (1 - 3)-linked residues in the dextrans. A number of dextrans have been hydrolysed by an exu-isomaltohydrolase (EC 3.2.1.94) from Arthrobacter globiformis to produce, in addition to isomaltose, one or two pentasaccharides in which an a-i>glucosyl residue is substituted at 0-2,0-3, or 0-4 by an isomaltosyl unit. ... 

Zehl973 Zehavi, U. and Patchomik, A., Oligosaccharide Synthesis on a Light-Sensitive Solid Support. I. The Polymer and Synthesis of Isomaltose (6-O-a-D-Glucopyranosyl-D-glucose), J. Am. Chem. Soc., 95 (1973) 5673-5677. 

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