摘要：

A simplification in the method of preparing triacetyl-β-D-xylopyranosylbenzene is described. This substance has been deacetylated to give crystalline β-D-xylopyranosylbenzene which, along with its crystalline tripropionate and tribenzoate, is described for the first time. The question of the stereochemical configuration of the anomeric center in β-D-xylopyranosylbenzene has been answered experimentally in the following way. The action of periodate on (β-D-xylopyranosylbenzene led to sirupy phenyldiglycolaldehyde. This in turn was oxidized to phenyldiglycolic acid, which was esterified and converted to its crystalline amide. The latter proved identical with an authentic sample of D( + )-2-phenyldiglycolamide prepared synthetically from L( + )-mandelic acid. The identity of the two samples establishes the anomeric center of β-D-xylopyranosylbenzene as possessing the 1,2-trans or β-configuration, a fact presumably capable of generalization to other low-rotating D-glycopyranosylaromatic hydrocarbons formerly designated β- in view of their low specific rotations.

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