Glucose’s pentaacetate does not react with hydroxylamine, indicating the absence of a free —CHO group. This contradicts the open-chain structure (I) and suggests a different configuration.

Glucose does not react with Schiff’s test or form a hydrogensulphite addition product due to the absence of a free —CHO group. The open-chain structure (I) fails to explain these observations.

The lowest asymmetric carbon atom is considered for assigning the configuration of monosaccharides. In glucose, for example, the comparison is made based on the position of the -OH group on the lowest asymmetric carbon, comparing it to the corresponding position ...

‘D’ and ‘L’ notations in carbohydrate nomenclature indicate the relative configuration of a stereoisomer concerning the known configuration of glyceraldehyde. Compounds chemically correlated to the D isomer of glyceraldehyde are assigned D-configuration, and those correlated to the L isomer are ...

The ‘D’ in D(+)-glucose represents its configuration, specifically indicating its relation to the D isomer of glyceraldehyde. It is not directly related to the optical activity of the compound, which is denoted by the ‘(+)’ symbol representing its dextrorotatory nature.