Chapter 24, Problem 24.41AP

Interpretation Introduction

(a)

Interpretation:

Raffinose is to be classified as a reducing or nonreducing sugar. The explanation for the answer is to be stated.

Concept introduction:

Carbohydrates are a class of organic compounds. Carbohydrates have the general molecular formula, ${\left({\text{CH}}_{\text{2}}\text{O}\right)}_{\text{n}}$.

The six-membered ring form of carbohydrates is termed as pyranose. The five-membered ring form of carbohydrates is termed as furanose.

The pyranoses can be classified as $\text{α}$ or $\text{β}$ based upon the configuration at the anomeric carbon. The anomeric carbon is the one which was a part of the carbonyl group in the straight-chain structure of the carbohydrate.

Interpretation Introduction

(b)

Interpretation:

The identification of glycoside linkages in raffinose is to be predicted. The classification of their $\text{α}$ and $\text{β}$ form is to be stated.

Concept introduction:

Carbohydrates are a class of organic compounds. They can be present in the form of open chains or rings. They are usually an aldehyde or ketone with additional hydroxyl groups. They have the general molecular formula, ${\left({\text{CH}}_{\text{2}}\text{O}\right)}_{\text{n}}$.

The six-membered ring form of carbohydrates is termed as pyranose. The five-membered ring form of carbohydrates is termed as furanose.

The pyranoses can be classified as $\text{α}$ or $\text{β}$ based upon the configuration at the anomeric carbon. The anomeric carbon is the one which was a part of the carbonyl group in the straight-chain structure of the carbohydrate.

Interpretation Introduction

(c)

Interpretation:

The monosaccharides formed when raffinose is hydrolyzed in aqueous acid is to be identified.

Concept introduction:

Carbohydrates are a class of organic compounds. They can be present in the form of open chains or rings. They are usually an aldehyde or ketone with additional hydroxyl groups. They have the general molecular formula, ${\left({\text{CH}}_{\text{2}}\text{O}\right)}_{\text{n}}$.

The anomeric carbon is the one which is a part of the carbonyl group in the straight-chain structure of the carbohydrate.

Interpretation Introduction

(d)

Interpretation:

The product formed when raffinose is treated with dimethyl sulfate in $\text{NaOH}$ in the presence of aqueous acid and heat is to be stated.

Concept introduction:

The linkage between the two carbohydrate group is known as the glycosidic linkage. These are of two types. One is $\text{α-}$ glycosidic linkage and other is $\text{β}$-glycosidic linkage. The $\text{α-}$ glycosidic linkage is formed when the anomeric hydroxyl group indulges at axial position. The $\text{α-}$ glycosidic linkage is formed when the anomeric hydroxyl group indulges at the equatorial position.