Deck 25: Carbohydrates

Question 1

What are the R/S stereochemical designations of C2 and C3 of L-threose?

A)2R,3R
B)2R,3S
C)2S,3R
D)2S,3S

Answer 1

2R,3S

Question 2

Which of the following is a disaccharide?

A)glucose
B)fructose
C)sucrose
D)mannitol

Answer 2

sucrose

Question 3

What is (are) the major organic product(s) obtained from the following reaction?

A)only 1
B)only 2
C)only 2 and 3
D)1, 2 and 3

Answer 3

only 2 and 3

Question 4

Which carbon in the following carbohydrate is the anomeric carbon?

A)i
B)ii
C)iii
D)iv

Question 5

Which of the following structures represent the same carbohydrate?

A)only 1 and 2
B)only 1 and 3
C)only 2 and 3
D)1, 2 and 3

Question 6

What is the major organic product obtained from the following reaction?

A)only 1
B)only 2
C)only 3
D)only 1 and 2

Question 7

Which carbon in the following carbohydrate is the anomeric carbon?

A)i
B)ii
C)iii
D)iv

Question 8

What is the relationship between D-erythrose and D-threose?

A)constitutional isomers
B)enantiomers
C)diastereomers
D)tautomers

Question 9

What is the relationship between D-arabinose and L-arabinose?

A)constitutional isomers
B)enantiomers
C)diastereomers
D)tautomers

Question 10

Which of the following represents a pyranose?

A)only 1
B)only 2
C)only 3
D)only 1 and 2

Question 11

Which of the following structures represent the same carbohydrate?

A)only 1 and 2
B)only 1 and 3
C)only 2 and 3
D)1, 2 and 3

Question 12

What is the major organic product obtained from the following reaction?

A)1
B)2
C)3
D)4

Question 13

Which of the following represents a furanose?

A)only 1
B)only 2
C)only 3
D)only 2 and 3

Question 14

Which of the following has a D-configuration?

A)only 1 and 2
B)only 1 and 3
C)only 2 and 3
D)only 1, 2 and 3

Question 15

What is the relationship between D-ribose and D-xylose?

A)constitutional isomers
B)enantiomers
C)diastereomers
D)tautomers

Question 16

Which of the following has a D-configuration?

A)only 1 and 2
B)only 1 and 3
C)only 2 and 3
D)only 1, 2 and 3

Question 17

Which of the following represent a ketose?

A)only 1 and 2
B)only 1 and 3
C)only 2 and 3
D)1, 2 and 3

Question 18

What are the R/S stereochemical designations of C2 and C3 of D-erythrose?

A)2R,3R
B)2R,3S
C)2S,3R
D)2S,3S

Question 19

Which of the following represent an aldose?

A)only 1 and 2
B)only 1 and 3
C)only 2 and 3
D)1, 2 and 3

Question 20

What is the relationship between D-threose and L-threose?

A)constitutional isomers
B)enantiomers
C)diastereomers
D)tautomers

Question 21

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
Structure ____ represents a aldopentose.

Question 22

Which of the following is vitamin C?

A)D-glucose
B)D-mannitol
C)L-ascorbic acid
D)L-sorbose

Question 23

Starch, cellulose, and surcrose are all classified as polysaccharides.

Question 24

Which of the following is not a polysaccharide?

A)amylose
B)amylopectin
C)glycogen
D)ribulose

Question 25

Oxidation of optically active D-erythrose with nitric acid produces optically inactive meso-tartaric acid (below). The structure of D-erythrose is shown below.

Question 26

Consider the following Fisher projections. They all convert to the same tetrahedral representation as shown below..

Question 27

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
The formula for maltose is: The number of the acetal carbon is _____.

Question 28

The following structure shows the correct assignment of the R or S configuration to each chirality center in sorbose.

Question 29

The following compound will react with Tollens' solution.

Question 30

Reduction of an optically active aldopentose with NaBH₄ gives an optically inactive alditol. The aldopentose could be:

Question 31

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
The structures that represent reducing sugars are:
a. only the ketoses.
b. only the aldoses.
c. all of these structures.

Question 32

The following are two different methods of representing the same structure.

Question 33

A 1,4- $\alpha$ -linkage between two glucose units produces a disaccharide called maltose.

Question 34

Consider the structure shown below. The Haworth projection formula for the pyranose form of $\beta$ -D-galactose is given below.

Question 35

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
Structure ____ represents a ketohexose.

Question 36

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
The number of hydroxyl groups in the pyranose form of glucose is _____.

Question 37

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
The number of the anomeric carbon in the following structure is _____.

Question 38

A glycoside is formed upon reaction of glucopyranose with NaBH₄.

Question 39

The difference between the pyranose and furanose forms of a given aldohexose is the ring size.

Question 40

Which of the following is an alditol?

A)glucose
B)fructose
C)glucaric acid
D)mannitol

Question 41

What is the major organic product obtained from the following reduction of glucose?

Question 42

From the sugars below, choose the one that best fits each description below. Place the letter of the sugar in the blank to the left of the description. There is only one correct answer for each question.
_____ is a sugar with three chirality centers.

A)
B)
C)
D)

Question 43

From the sugars below, choose the one that best fits each description below. Place the letter of the sugar in the blank to the left of the description. There is only one correct answer for each question.
_____ is a deoxy sugar.

A)
B)
C)
D)

Question 44

The textile rayon is produced by treatment of cellulose with carbon disulfide in aqueous sodium hydroxide. What type of functional group is introduced on the cellulose under these conditions?

Question 45

Complete the structure on the right so that it represents the pyranose form of the carbohydrate shown on the left as a Fischer projection. Place the substituents carefully so that their position in axial or equatorial positions accurately reflects the stereochemistry of the carbohydrate.

Question 46

What are the major organic products obtained from treatment of a methyl glycoside with periodic acid in water?

Question 47

From the sugars below, choose the one that best fits each description below. Place the letter of the sugar in the blank to the left of the description. There is only one correct answer for each question.
_____ is a sugar which yields a single alditol upon reduction.

A)
B)
C)
D)

Question 48

The textile cellulose acetate is produced by treatment of cellulose with acetic anhydride. What type of functional group is introduced on the cellulose under these conditions?

Question 49

Consider the following structures. Answer the following questions by placing the appropriate number or indicated letter in the blank.
The following monosaccharide has ________ equatorial hydroxyl groups.

Question 50

Complete the structure on the right so that it represents the pyranose form of the carbohydrate shown on the left as a Fischer projection. Place the substituents carefully so that their position in axial or equatorial positions accurately reflects the stereochemistry of the carbohydrate.

Question 51

Refer to the equilibrium below to answer the following question(s).

-The correct name for the cyclic structure is__________________________.

Question 52

What is the major organic product obtained from the reaction of glucose with glucose oxidase?

Question 53

From the sugars below, choose the one that best fits each description below. Place the letter of the sugar in the blank to the left of the description. There is only one correct answer for each question.
_____ is a D-sugar.

A)
B)
C)
D)

Question 54

Refer to the equilibrium below to answer the following question(s).
The enantiomer of ribose is drawn is _______. (D or L)

Question 55

From the sugars below, choose the one that best fits each description below. Place the letter of the sugar in the blank to the left of the description. There is only one correct answer for each question.
The fundamental difference between the monosaccharide, disaccharide, and polysaccharide classifications of carbohydrates is the number of _________________present.

Question 56

Refer to the equilibrium below to answer the following question(s).

-The anomer of ribose is drawn is _______. (alpha or beta)

Question 57

What are the major organic products obtained from treatment of a 1,2,3-triol with periodic acid in water?

Question 58

From the sugars below, choose the one that best fits each description below. Place the letter of the sugar in the blank to the left of the description. There is only one correct answer for each question.
The name of the following Fischer projection including stereochemistry is _____________________.

Question 59

What are the two major organic products obtained from treatment of an $\alpha$
-hydroxyketone with periodic acid in water?

Question 60

What are the two major organic products obtained from the following reaction? What is the relationship between them? (What type of isomers are they?)