Question 1

Provide the open-chair structures of the two monosaccharides that result when D-threose undergoes the Kiliani-Fischer synthesis.

Accepted Answer

The answer of Provide the open-chair structures of the two...

Question 2

What nucleophilic carbon species is used in the Kiliani-Fischer synthesis?

Accepted Answer

cyanide

Question 3

At which carbon are the following sugars epimers of each other?

Accepted Answer

A) C-1 
B) C-2 
C) C-3 
D) C-4 
E) C-5 
A) C-1 
B) C-2 
C) C-3 
D) C-4 
E) C-5 C

Question 4

Under what conditions is the methyl glycoside of galactose prepared?

Accepted Answer

CH₃OH, H+ (

Question 5

Anomers of D-glucopyranose differ in their stereochemistry at ________.

Accepted Answer

A) C1 
B) C2 
C) C3 
D) C4 
E) C5 
A) C1 
B) C2 
C) C3 
D) C4 
E) C5

Question 6

Give the major product(s)for the following reaction.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 7

Which of the following statements best describes the difference between amylose and amylopectin?

Accepted Answer

A) Amylose is a branched polysaccharide while amylopectin is a chain polysaccharide. 
B) Amylose is a straight-chain polysaccharide while amylopectin is a branched polysaccharide. 
C) Amylose contains α-1,6-glycosidic linkage which amylopectin does not contain. 
D) Amylose is composed of thousands of D-glucose units while amylopectin is composed of thousands of D-galactose units. 
E) Amylose is one of the largest molecules found in nature while amylopectin is one of the smallest molecules found in nature. 
A) Amylose is a branched polysaccharide while amylopectin is a chain polysaccharide. 
B) Amylose is a straight-chain polysaccharide while amylopectin is a branched polysaccharide. 
C) Amylose contains α-1,6-glycosidic linkage which amylopectin does not contain. 
D) Amylose is composed of thousands of D-glucose units while amylopectin is composed of thousands of D-galactose units. 
E) Amylose is one of the largest molecules found in nature while amylopectin is one of the smallest molecules found in nature.

Question 8

Which of the following is the cyclic hemiacetal formed from 4-hydroxyheptanal?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
E) V 
A) I 
B) II 
C) III 
D) IV 
E) V

Question 9

A carbohydrate composed of three to ten sugar molecules is called a(n)________.

Accepted Answer

A) single carbohydrate 
B) disaccharide 
C) oligosaccharide 
D) polysaccharide 
E) monosaccharide 
A) single carbohydrate 
B) disaccharide 
C) oligosaccharide 
D) polysaccharide 
E) monosaccharide

Question 10

Give the name for the following compound.

Accepted Answer

A) a-maltose 
B) b-maltose 
C) a-cellobiose 
D) b-cellobiose 
E) a-lactose 
A) a-maltose 
B) b-maltose 
C) a-cellobiose 
D) b-cellobiose 
E) a-lactose

Question 11

Provide the Fischer projection of the open-chain form of the aldonic acid which results when L-glucose is treated with bromine water.

Accepted Answer

The answer of Provide the Fischer projection of the open-chain...

Question 12

An optically active D-aldopentose A produced an optically active alditol B upon treatment with sodium borohydride. When this aldopentose was subjected to a Ruff degradation, a D-aldotetrose C was generated. This aldotetrose yielded an optically inactive aldaric acid D upon oxidation with nitric acid. Use these data to provide the structures of compounds A, B, C, and D.

Accepted Answer

The answer of An optically active D-aldopentose A produced an...

Question 13

Which of the following is true about sucrose?

Accepted Answer

A) It hydrolyzes to fructose and glucose. 
B) It is a reducing sugar. 
C) It is a monosaccharide. 
D) It undergoes mutorotation in water. 
A) It hydrolyzes to fructose and glucose. 
B) It is a reducing sugar. 
C) It is a monosaccharide. 
D) It undergoes mutorotation in water.

Question 14

Which of the following compounds is a nonreducing sugar?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
E) V 
A) I 
B) II 
C) III 
D) IV 
E) V

Question 15

Give the major product(s)for the reaction.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 16

Which of the following best describes the sugar D-galactose,

Accepted Answer

A) D-aldohexose 
B) D-ketohexose 
C) L-aldohexose 
D) L-ketohexose 
E) D-aldopentose 
A) D-aldohexose 
B) D-ketohexose 
C) L-aldohexose 
D) L-ketohexose 
E) D-aldopentose

Question 17

Provide the structure of the more stable chair conformer which results when β-D-galactose is treated with excess acetic anhydride/pyridine.

Accepted Answer

The answer of Provide the structure of the more stable...

Question 18

Name the following structure.

Accepted Answer

A) amylopectin 
B) amylose 
C) lactose 
D) cellulose 
E) starch 
A) amylopectin 
B) amylose 
C) lactose 
D) cellulose 
E) starch

Question 19

Draw the Fischer projection for the open-chain form of D-glucose.

Accepted Answer

The answer of Draw the Fischer projection for the open-chain...

Question 20

An optically active D-aldopentose produced an optically inactive aldaric acid upon treatment with HNO3. When this aldopentose was subjected to a Ruff degradation, a D-aldotetrose was generated. This aldotetrose gave an optically inactive alditol upon reduction with NaBH4. Use these data to provide the structure of the starting D-aldopentose.

Accepted Answer

Exam 21: Carbohydrates

Provide the open-chair structures of the two monosaccharides that result when D-threose undergoes the Kiliani-Fischer synthesis.

What nucleophilic carbon species is used in the Kiliani-Fischer synthesis?

At which carbon are the following sugars epimers of each other?

Under what conditions is the methyl glycoside of galactose prepared?

Anomers of D-glucopyranose differ in their stereochemistry at ________.

Give the major product(s)for the following reaction.

Which of the following statements best describes the difference between amylose and amylopectin?

Which of the following is the cyclic hemiacetal formed from 4-hydroxyheptanal?

A carbohydrate composed of three to ten sugar molecules is called a(n)________.

Give the name for the following compound.

Provide the Fischer projection of the open-chain form of the aldonic acid which results when L-glucose is treated with bromine water.

Which of the following is true about sucrose?

Which of the following compounds is a nonreducing sugar?

Give the major product(s)for the reaction.

Which of the following best describes the sugar D-galactose,

Provide the structure of the more stable chair conformer which results when β-D-galactose is treated with excess acetic anhydride/pyridine.

Name the following structure.

Draw the Fischer projection for the open-chain form of D-glucose.

Remembering General Chemistry: Electronic Structure and Bonding

Acids and Bases: Central to Understanding Organic Chemistry

An Introduction to Organic Compounds

Isomers: the Arrangement of Atoms in Space

Alkenes Thermodynamics and Kinetics

Reactions of Alkenes

Reactions of Alkynes Introduction to Multistep Synthesis

Electron Delocalization, Resonance, and Aromaticity More About Molecular Orbital Theory

Substitution Reactions of Alkyl Halides

Elimination Reactions of Alkyl Halides Competition Between Substitution and Elimination

Reactions of Alcohols, Ethers, Epoxides, and Sulfur-Containing Compounds

Organometallic Compounds

Reactions of Alkanes, Radicals

Mass Spectrometry, Infrared Spectroscopy, and Uvvis Spectroscopy

Nmr Spectroscopy

Reactions of Carboxylic Acids and Carboxylic Acid Derivatives

Reactions of Aldehydes and Ketones

Reactions at the Alpha Carbon of Carbonyl Compounds

Reactions of Benzene and Substituted Benzenes

More About Amines Heterocylic Compounds

Amino Acids, Peptides, and Proteins

Catalysis

The Organic Mechanisms of the Coenzymes

The Chemistry of Metabolism

Nucleosides, Nucleotides, and Nucleic Acids

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