Glucose preparation

Methods of Formation.—The first sample of 4,6-dimethyl-D-glucose, prepared by Haworth and Sedgwick97 in 1926, came, together with tri-and tetramethylglucoses, from the incomplete methylation of glucose with methyl sulfate and sodium hydroxide. It was not characterized until about a decade later, when it was isolated by Bell and Synge98 from another source. 

The slightly impure product is recrystallized from petroleum ether (b.p. 30-60°) containing 0.5 per cent of anhydrous ether in a continuous extractor, using 100 cc. of solvent per 6-7 g. of compound. One crystallization is generally sufficient to give a pure product. The specific rotation of pure tetiamethyW-glucose prepared by this method is approximately [a] d + 81.3° (Note 4). 

To have proper solubility the tablets are formed from very finely dispersed drug mixtures. However, the process of tableting is not smooth if these powders are fed directly to the tableting machines. Granulation of the powders before tableting is usually required. Also, several pharmaceutical products, such as glucose preparations, are sold in granulated form. 

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