2,3,4,6-TETRAMETHYL-d-GLUCOSE

The presence of the pyranose ring in the two D-glucose units of melezitose was inferred by Zempl6n and Braun from good evidence, and made certain by Miss Leitch29 through the crystallization of the requisite amount of 2,3,4,6-tetramethyl-D-glucose from the scission products of the fully methylated trisaccharide. The revised interpretation of Miss Leitch s experimental data concerns only the structure of the... 

D-Glucose residue 1 would therefore appear as 2,3,4,6-tetramethyl-D-glucose on hydrolysis of methylated dextran D-glucose 2 as 2,3-dimethyl-D-glucose and the other three D-glucose residues as 2,3,4-tri-... 

On methylation of the disaccharide with dimethyl sulfate and sodium hydroxide a hexamethyl ether of the carbohydrate was obtained. When this fully methylated derivative (VII) was hydrolyzed with acid, 2,3,4,6-tetramethyl-D-glucose (VIII) and dimethyl-L-arabinose (IX) were produced. Since position 3 in the L-arabinose component of VI was shown to be occupied in glycosidic linkage with D-glucose, the dimethyl-L-arabinose could be either the 2,5- or 2,4-dimethyl derivative (IX),... 

Tetramethyl-D-glucose is frequently isolated after hydrolysis of the methyl ethers of naturally-occurring glucose polymers (e.g. maltose,... 

A nonreducing disaccharide gives an octamethyl derivative with dimethyl sulfate and alkali. On acid hydrolysis, this derivative yields 1 mol of 2,3,4,6-tetramethyl-D-glucose and 1 mol of 2,3,4,6-tetramethyl-D-galactose. The disaccharide is hydrolyzed rapidly by either maltase or lactase (a P-galactosidase). 

TETRAMETHYL-d-GLUCOSE, 20, 97 Tetramethylmethylglucoside, MIXTURE OF a AND j8, 20,100 Tetramethyl-tt-methylglucoside, 20, 99 Tetranitromethane, 21,105 Tetranitromethane as reagent for detecting double bonds, 21, 107 Tetraphenylcyclopentadienone, 23, 92, 93... 

Tetramethyl-D-glucose reaches equilibrium in benzene rapidly through the concerted action of cresol and pyridine as acid-base catalysts (Table 4.3). Bifunctional reagents, like 2-pyridone and benzoic acid, are especially efficient acid-base catalysts in both polar and nonpolar solvents ... 

Table 4.3. Mutarotation rate of 2,3,4,6-tetramethyl-D-glucose (0.09 mol/1) in benzene...

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