Chapter 20.14, Problem 28P

(a)

Interpretation Introduction

Interpretation:

The given compound has to be named and it is reducing sugar or not is to be predicted.

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.

Reducing sugar is the sugar which is capable to act as a reducing agent.  The sugar which contains aldehyde and ketone groups in free state acts as reducing sugar and the sugar which does not contain aldehyde and ketone group in free state are known as nonreducing sugars.

(b)

Interpretation Introduction

Interpretation:

The name of the given compound and it is reducing sugar or not is to be predicted.

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.

Reducing sugar is the sugar which is capable to act as a reducing agent.  The sugar which contains aldehyde and ketone groups in free state acts as reducing sugar and the sugar which does not contain aldehyde and ketone group in Free State are known as non-reducing sugars.

(c)

Interpretation Introduction

Interpretation:

The name of the given compound and it is reducing sugar or not is to be predicted.

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.

Reducing sugar is the sugar which is capable to act as a reducing agent.  The sugar which contains aldehyde and ketone groups in free state acts as reducing sugar and the sugar which does not contain aldehyde and ketone group in free state are known as nonreducing sugars.