20. Carbohydrates

Identify each of the following as D or L:

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Identify each of the following as the D or L enantiomer:

a. <IMAGE>

Draw the Fischer projection for the other enantiomer of a to b in problem 13.21.

Draw the Fischer projection for the other enantiomer of c to d in problem 13.21.

Draw the Fischer projections for D-glucose and L-glucose.

The sugar d-gulose is a sweet-tasting syrup. (13.3, 13.4)

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a. Draw the Fischer projection for l-gulose.

Identify the following monosaccharides as the d- or the l-isomer:

(a) <IMAGE> 

Use the structure of d-galactose in Problem 6.15 to answer the following: 

(b) Draw the Fischer projection of l-galactose.

How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the d- or l-isomer. 

(b) <IMAGE>

How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the d- or l-isomer.

(a) <IMAGE>