Chapter 20.15, Problem 30P

(a)

Interpretation Introduction

Interpretation:

The sugars present in the given compound amygdalin have to be identified.

Concept Introduction:

The naming of the reducing and nonreducing sugars is done on the basis of position of hydroxyl group present at each carbon atom in the sugar which is classified on the basis of alpha, beta, D and L sugars.

The sugar which has free aldehyde or ketone groups acts as reducing sugar.

The name of the sugar is determined on the basis of position of hydroxyl group which is given as,

• The sugar containing hydroxyl group on the carbon atom connected to methanol group on the right side is name as D sugar.
• The sugar containing hydroxyl group on the carbon atom connected to methanol group on the left side is name as L sugar.
• The sugar containing hydroxyl group on the carbon atom connected to oxygen atom at equatorial position is said to be alpha sugar.
• The sugar containing hydroxyl group on the carbon atom connected to oxygen atom at axial position is said to be beta sugar.
• The name of alkyl group attached to the hydroxyl groups written before the name of sugar.

(b)

Interpretation Introduction

Interpretation:

The type of glycosidic linkage present in the sugar amygdalin is to be identified.

Concept Introduction:

Glycosidic bond is the bond present between two monosaccharide molecules which are bonded together to form a disaccharide molecule.  If both the monosaccharide molecules are connected through equatorial-equatorial or axial-axial positions, then the linkages present are alpha linkages and the sugars connected through axial-equatorial positions, then the linkage is beta linkage.