Chapter 18, Problem 18.63EP

(a)

Interpretation Introduction

Interpretation: The Fischer projection formula for $\text{D}-\text{glucose}$ has to be drawn.

Concept introduction: The Fischer formula can be drawn by using the following rules.

• Ø The chiral center is assumed to be in the plane of paper.
• Ø Two of the bonds are considered pointing towards the page.
• Ø Two of the bonds are considered pointing outwards of the page.
• Ø The intersection of horizontal and vertical lines represents the chiral centre.
• Ø The horizontal lines are the lines pointing outwards of the page.
• Ø The vertical lines are the lines pointing towards the page.

Answer to Problem 18.63EP

The Fischer projection formula for $\text{D}-\text{glucose}$ is,

Explanation of Solution

The given molecule is $\text{D}-\text{glucose}$.  The molecular formula of $\text{D}-\text{glucose}$ is ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_{\text{6}}$.  The Fisher projection $\text{D}-\text{glucose}$ is shown as,

The monosaccharide, $\text{D}-\text{glucose}$ contains a backbone of six carbon atoms with an aldehyde as a functional group.

(b)

Interpretation Introduction

Interpretation: The Fischer projection formula for $\text{D}-\text{glyceraldehyde}$ has to be drawn.

Concept introduction: The Fischer formula can be drawn by using the following rules.

• Ø The chiral center is assumed to be in the plane of paper.
• Ø Two of the bonds are considered pointing towards the page.
• Ø Two of the bonds are considered pointing outwards of the page.
• Ø The intersection of horizontal and vertical lines represents the chiral center.
• Ø The horizontal lines are the lines pointing outwards of the page.
• Ø The vertical lines are the lines pointing towards the page.

Answer to Problem 18.63EP

The Fischer projection formula for $\text{D}-\text{glyceraldehyde}$ is,

Explanation of Solution

The given molecule is $\text{D}-\text{glyceraldehyde}$.  The molecular formula of $\text{D}-\text{glyceraldehyde}$ is ${\text{C}}_{\text{3}}{\text{H}}_{\text{6}}{\text{O}}_{\text{3}}$.  The Fisher projection $\text{D}-\text{glyceraldehyde}$ is shown as,

The monosaccharide, $\text{D}-\text{glyceraldehyde}$ contains a backbone of three carbon atoms with an aldehyde as a functional group.

(c)

Interpretation Introduction

Interpretation: The Fischer projection formula for $\text{D}-\text{fructose}$ has to be drawn.

Concept introduction: The Fischer formula can be drawn by using the following rules.

• Ø The chiral center is assumed to be in the plane of paper.
• Ø Two of the bonds are considered pointing towards the page.
• Ø Two of the bonds are considered pointing outwards of the page.
• Ø The intersection of horizontal and vertical lines represents the chiral center.
• Ø The horizontal lines are the lines pointing outwards of the page.
• Ø The vertical lines are the lines pointing towards the page.

Answer to Problem 18.63EP

The Fischer projection formula for $\text{D}-\text{fructose}$ is,

Explanation of Solution

The given molecule is $\text{D}-\text{fructose}$.  The molecular formula of $\text{D}-\text{fructose}$ is ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_6$.  The Fisher projection $\text{D}-\text{fructose}$ is shown as,

The monosaccharide, $\text{D}-\text{fructose}$ contains a backbone of six carbon atoms with a ketone as a functional group.

(d)

Interpretation Introduction

Interpretation: The Fischer projection formula for $\text{L}-\text{galactose}$ to be drawn.

Concept introduction: The Fischer formula can be drawn by using the following rules.

• Ø The chiral center is assumed to be in the plane of paper.
• Ø Two of the bonds are considered pointing towards the page.
• Ø Two of the bonds are considered pointing outwards of the page.
• Ø The intersection of horizontal and vertical lines represents the chiral center.
• Ø The horizontal lines are the lines pointing outwards of the page.
• Ø The vertical lines are the lines pointing towards the page.

Answer to Problem 18.63EP

The Fischer projection formula for $\text{L}-\text{galactose}$ is,

Explanation of Solution

The given molecule is $\text{L}-\text{galactose}$.  The molecular formula of $\text{L}-\text{galactose}$ is ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_6$.  The Fisher projection $\text{L}-\text{galactose}$ is shown as,

The monosaccharide, $\text{L}-\text{galactose}$ contains a backbone of six carbon atoms with an aldehyde as a functional group.