Only the confguration of the hemiacetal function is affected in this process. The aconfguration ofthe glycosidic linkage remains unchanged.25.13Write the chemical equation so that you can clearly relate the product to the starting material.Ribitol is a meso form; it is achiral and thus not optically active. A plane of symmetry passingthrough C-3 bisects the molecule.25.14(b)Arabinose is a reducing sugar; it will give a positive test with Benedict’s reagent, because itsopen-chain form has a free aldehyde group capable of being oxidized by copper(II) ion.(c)Benedict’s reagent reacts with a-hydroxy ketones by way of an isomerization process involv-ing an enediol intermediate.1,3-Dihydroxyacetone gives a positive test with Benedict’s reagent.(d)D-Fructose is an a-hydroxy ketone and will give a positive test with Benedict
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This note was uploaded on 10/03/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.