Inososes osazones

The chemistry of carba sugars is quite similar to that of cyclitols both groups lack the latent carbonyl groups of their saccharide counterparts, and therefore fail to exhibit many of the characteristic properties of monosaccharides. Thus carba sugars and cyclitols do not form hydrazones or osazones, nor do they mutarotate, or reduce heavy-metal salts in base, in contrast to their oxidation products, the inososes. 

The structure of inosose bis(phenylhydrazones) resembles that of saccharide osazones in that the bishydrazone residues in both are chelated that is, bridged by an imino group (the other NH group is unchelated). 

Inososes, like hexoses, form osazones when treated with phenylhydrazine, so that the isolation of osazones from the oxidation products is not, in itself, evidence of the formation of a-diketoinositols. 

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