Metasaccharinic acid degradation

Machell and Richards and Colbran and Davidson. . . assumed that degradation ceased not only when the reducing terminal unit of cellulose was converted into a metasaccharinic acid residue but also when the reactant end of the molecule reached inaccessible (crystalline) regions of the cellulose fiber... . The available data indicate that the less ordered portions of cellulose are the more reactive. Thus the rate of oxidation of... 

Figure 9.3 Mechanism of the formation of isosaccharinic acid and metasaccharinic acid during alkaline cellulose degradation.

Two metasaccharinic acids have been obtained from glucose. These have retained the original configuration of the carbon atoms at 4 and 5, since they give 2-deoxy-D-ribose upon degradation and since one is identical with the synthetic 3-deoxy-D-ara6mo-hexonic acid IO4, 105). (See Chapter II, also.)... 

From 3-0-methyl-D-xylose are formed the two analogous five-carbon metasaccharinates. The main component of the reaction mixture is 3-deoxy-D- ljrxonate, although small amounts of 3-deoxy-D- xylonate are also found. Furthermore, 3-0-a-D-xylopyranosyl-L-arabinose is degraded, in lime water, to an acid salt and n-xylose. Alkaline degradation of 3-0-... 

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