Fructose phenylhydrazone

Colorless phenylhydrazones of 1-deoxy-l-piperidino- and 1-deoxy-l-morpholino-D-fructose were prepared by Hodge and Rist. Only a small excess of phenylhydrazine, without any acetic acid, was used (in order to prevent osazone formation, because osazones are known to be readily formed from Amadori rearrangement products in the presence of acids). 

Topper and Stetten s work involved (1) the reaction of n-glucose-l-d in ordinary water saturated with calcium hydroxide, and (2) the reaction of D-glucose in deuterium oxide saturated with calcium hydroxide-d2. These isomerizations were carried out at both 25° and 35°. In the experiments with D-glucose-l-d at 35°, the n-mannose isolated (as the phenylhydrazone) contained 44 % of the deuterium in the starting substance, all of which was retained at Cl, whereas the n-fructose isolated (as the phenylosazone) retained 94% of the deuterium. A similar result (100% retention of deuterium) was reported for the n-fructose isolated from the reaction at 25°. These figures for n-fructose were based on the assumption that 50 % of the... 

Chemical Properties of d-Fructose.—The carbohydrate forms a phenylhydrazone when treated with phenylhydrazine when heated in aqueous solution with an excess of the hydrazine, an osazone is formed, which is identical with d-glucosazone. The... 

D-Fructose 102-104° —92° 2,5-Dichloro- phenylhydrazone Di-isopropylidene 28 154° Fruit juices, blood of foetal ungulates Oligosaccharides notably sucrose. Inulins and Icvans... 

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