Of D-glucosone

Partially methylated derivatives of D-glucosone have been prepared by decomposition of the corresponding partially methylated phenylosazones with p-nitrobenzaldehyde osones have been obtained from 5-0-methyl-D-glucose phenylosazone and from 3,4,5-tri-O-methyl-D-glucose phenylosazone in this way.22 Although 6-0-methyl-D-glucose phenylosazone is not altered by heating with benzaldehyde or piperonal in aqueous ethanolic... 

Weidenhagen48 further investigated this reaction he found that osone formation could become the main reaction if ethanol or methanol was used as a solvent, the cupric acetate was not in excess, and the reaction time was limited. Oxidation of D-glucose or D-fructose was reported to give a 40% yield of D-glucosone.14-46... 

In the preparation of D-glucosone by the direct oxidation of D-glucose, D-fructose, or D-mannose by such reagents as that of Fenton,37 cupric acetate,16- 46- 46 selenious acid,16-61 etc., the degree of oxidation must be carefully controlled if the osone, which is the first product, is to be the main product of the reaction. The nature and mechanism of formation of the products of further oxidation of D-glucosone are discussed on p. 68. 

Neither of these reports has been confirmed, and, in both cases, evidence for the production of D-glucosone is incomplete, being based mainly on the preparation of non-definitive derivatives. These results are discussed more fully in the Section dealing with the biological significance of the osones. 

Treatment with mineral acid of the insoluble lead complex of D-glucosone regenerates the free sugar.3 38... 

The reaction of D-glucosone and other osones with cyanide, as a first stage in the synthesis of ascorbic acid and its analogs, has been reviewed by Smith.136... 

Interest in the possible intermediary role of D-glucosone has been revived by the work of Becker and Day101 who fed D-glucose-l-C14 and D-glucosone-... 

Berkeley96 investigated oxidase action in preparations obtained from the crystalline style of the mollusc, Saxidomus giganteus. He demonstrated the aerobic and anaerobic production of D-glucosone by separate systems, each of which comprised a component in the style and another in the diatomaceous food of the mollusc. The osone was identified through the formation of D-glucose m-nitrophenylosazone and by reduction with zinc... 

Fischer1-2 decided that the mode of formation, the reactions with hydrazines, aromatic diamines, and oxidizing agents, and the reduction to D-fructose could be explained by attributing to the open-chain form of D-glucosone the a-ketoaldehyde structure L. 

The two chief structural types which have to be considered are (a) those with a single lactol ring and a free or hydrated carbonyl group and (b) those in which two lactol rings are present. There is at present no conclusive evidence that either type of structure is the main component of D-glucosone in solution. Glycoside formation does not proceed normally in the osones,... 

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