Glucosone hydrate

Tetra Acetyl Glucosone Hydrate. A Novel Route to the Syntheses of Analogues of Ascorbic Acid and a Possible Mechanism for the Transformation of Hexoses into Kojic Acid, M. Stacey and L. M. Turton, J. Chem. Soc., (1946) 661 -664. 

Often, the osone hydrate crystallizes spontaneously within a few minutes after the addition of water and may be extracted from the contaminating salts with chloroform. Additional crystals may be obtained by adding petroleum ether to the ethereal mother liquor. 2,3,4,6-Tetra-O-acetyl-D-glucosone hydrate is soluble in water, ethanol, and chloroform difficultly soluble in ether or benzene and insoluble in petroleum ether.16... 

Stacey and Turton61 tried to produce the osone hydrate directly by oxidation of 2,3,4,6-tetra-0-acetyl-(2-hydroxy-D-glucal) with an ethereal solution of perbenzoic acid. A discrepancy exists in the constants reported for the specimens of 2,3,4,6-tetra-O-acetyl-D-glucosone hydrate prepared... 

Stacey and Turton61 showed that 2,3,4,6-tetra-O-acetyl-D-glucosone hydrate can be used in two of the established methods for the production of analogs of ascorbic acid. Methods of preparation, reactions, and importance of this class of compound have been reviewed previously.62 Addition of hydrogen cyanide to 2,3,4,6-tetra-O-acetyl-D-glucosone hydrate, and hydrolysis by the usual methods, led to a keto-acid (not isolated) which was converted by enolization and lactonization to D-gluco-ascorbic acid monohydrate, isolated in 50% yield. The product was identified by its (52) F. Smith, Advances in Carbohydrate Chem., 2, 79 (1946). 

Tetra-O-acetyl-D-glucosone hydrate was reduced by Maurer and Bohme63 in 50% acetic acid with hydrogen over a palladium catalyst to a crystalline compound, C14H20O10, of m.p. 158°, [< ]d —32° (in... 

Alduloses, Sugar Acids, and their Derivatives.- The trl-O-lsopropy-lidene derivative (1 ) of D-glucosone hydrate,ammonium 3-deoxy-... 

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,... 

Interest in these osone derivatives was originally stimulated49 by Hynd s60 report on certain similarities between physiological responses to D-glucosone and to insulin. The most recent studies have been part of the effort to find better routes for the preparation of ascorbic acid and its analogs.12 61 An additional point of interest was found in the ready conversion of the osone hydrates to kojic acid,6 which was attracting considerable interest as a product of the metabolism of certain microorganisms. 

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