D-Idose

D-Allose D-Altrose D-Glucose D-Mannose D-Gulose D-Idose D-Galactose D-Talose... 

When heated to 100 CC/ D-idose undergoes a reversible loss of water and exists primarily as 1,6-anhydro-n-idopyranose. 

Acetolysis of LXXIV gives, as might be expected, a mixture of the acetates of n-mannose and D-idose and as the dianhydro sugar has a free hydroxyl on C2, it should prove to be a source of 2-substituted n-mannose or D-idose and of 2,4-derivatives of n-mannose and 2,3-derivatives of D-idose. 

A. C. Richardson and H. O. L. Fischer, Cyclization of dialdehydes with nitromethane, Part VI. Preparation of 3- amino-1,6-anhydro-3-deoxy-p-D-gulose, -P-D-altrose and -p-D-idose derivatives and their characterization by means of inversion of mesyloxy groups,./. Am. Chem. Soc., 83 (1961) 1132-1139. 

Y. Ali and A. C. Richardson, Nucleophilic replacement reactions of sulphonates. III. The synthesis of derivatives of2,3,4,6-tetra-acetamido-2,3,4,6-tetradeoxy-D-galactose and-D-idose,/. Chem. Soc., Sect. C (1968) 1764-1769. 

Neighboring-group participation by the vicinal, trans-acetoxyl group (see p. 125) serves to explain the abnormal behavior of methyl 4-0-acetyl-2,3-anhydro-6-0-benzyl- or -trityl-a-D-gulopyranoside with hydrogen chloride in acetone, or with 80% aqueous acetic acid, which give D-galactose, instead of the D-idose, derivatives.67 In the same way, 2-0-acetyl-3,4-anhydro-D-altropyranosides yield D-man-nosides, not D-idosides.9 6z(see p. 125). 

As a consequence, 4,6-O-isopropylidene derivatives are obtained from D-aldohex-oses this has now been demonstrated not only for D-allose, D-galactose, D-glucose, D-mannose, and D-talose, but also for D-gulose (J. Gelas and D. Horton, unpublished results see also, Ref. 15) it may reasonably be assumed that it will also be found for D-altrose and D-idose. 

Gross and Oriez125 reported the synthesis of 4-S-acetyl-6-deoxy-4-thio-D-altrose (302) and 4-S-acetyl-6-deoxy-4-thio-D-idose (303) by using, as starting materials, the corresponding thiocyanates prepared in 35% yield from the 4-O-mesyl derivatives 298 and 299 by Sn2 displacement with thio-... 

D-allose D-altrose D-glucose D-mannose D-gulose D-idose D-galactose D-talose... 

D-Glucose and D-mannose D-Gulose and D-idose D-Galactose and D-talose... 

A-4. jS-D-Idopyranose (jS-pyranose form of D-idose) A-5. The products are diastereomers. 

E. Sorkin and T. Reichstein, D-Idose aus D-Galaktose, Helv. Chim. Acta, 28 (1945) 1-17. 

By treatment of D-gulose (XVII) or D-idose (XVIII) with warm aqueous barium hydroxide solution Van Ekenstein and Blanksma were able to isolate D-sorbose (II) with a melting point of 165° and [< ]d + 42.9° in water. The aldoses were prepared from D-gulonic and D-idonic lactones obtained by the cyanohydrin synthesis from D-xylose. 

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