Sugars, reducing derivatives

Along with permethylated derivatives, the permethylated, LiAlH4-reduced derivatives of glycolipids are also used for mass-spectrometric analysis. The amide groups of acetamido sugars and the ceramide part are reduced to alkylamino groups, and, in the case of gangliosides, the ester... 

The experimental data allow the following interpretation of the mechanism. By the action of hydrogen sulfide, the sugar formazan (I) is reduced to a sugar hydrazidine derivative (II), which becomes protonized (III) in the course of a slow SnI process, the hydrazidine ion splits off phenylhydrazine, whereafter the arising carbonium ion (IV) unites in a rapid... 

Two general methods for the synthesis of uronic acids have been developed (1) the reduction of the monolactones of aldaric acids, and (2) the oxidation of primary alcoholic groups of sugars or derivatives. The monolactones of dibasic acids can be reduced by sodium amalgam in acid solution... 

Reducing sugars reduce nitrophenols to deeply colored derivatives. Picric acid, C6H20H(N02)3, is transformed to the deep-red salt of picramic acid, C6H2(N02)2(NH2)0H. For o-dinitrobenzene, the test is so sensitive that 6 parts per 1,000,000 of reducing sugars may be detected. 

The above chemicals can be obtained by fermentation (qv) of other sugars. However, some compounds require sucrose as a unique feedstock. Examples are the polysaccharides dextran, alteman, andlevan, which are produced by specific strains of bacteria (48,54—56). Dextrans are used to make chromatographic separation media, and sulfated dextran derivatives are used as plasma extenders (41). Levans show promise as sweetness potentiators and, along with alteman, have potential as food thickeners and bulking agents in reduced-caloric foods (55,56) (see Carbohydrates). 

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