Chem 30B          April 4, 2001         Name ________________________

2nd hour exam                                                                                   please print

108 points     Points are in the left margin, e.g., [6]    Seager, Chpts 5-7

 

Some questions have more than one correct answer. Don’t crowd your answers. Use the back if necessary.

 

1. Draw structures for these organic compounds.

 

[5]  a. the organic product of the hydrolysis of acetamide

 

 

 

[5] b. the dimethylester of phosphoric acid

 

 

[5]   c. a Fisher projection of a tertiary (3°) amine with formula C4 H11NO and 1 chiral carbon

 

 

[5] d. alpha-D-galactose

 

 

 

 

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  1. Fill in the blanks.

[2]   a. Neurotransmitters in our bodies usually contain which functional group?

        amino .

[3]   b. In terms of chemical reactions, the most important difference between an amine nitrogen and an amide nitrogen is:

 Amine N is basic; amide is neutral.

[3]   c.  Lactose consists of galactose  bonded to glucose  by a

 beta 1--> 4 glucoside link.

[2]   d. A hemiacetal is always in equilibrium with a aldehyde (or carbonyl)  and a alcohol (or hydroxyl)

3. [5] Give a complete name for

 

 

 

 

4-isopropyl-N,N-diethylaniline

 

 

 

 

4. a. Draw the structure of an  L-aldotetrose.   b.  Draw the structure of its enantiomer. 

 c. Draw the structure of one of its diastereomers. d. Is this diastereomer L or D? D [2]

 

a. L-aldotetrose

 

b. enantiomer

 

 

c. diastereomer

 

 

5. a. [4] In the following compound circle and label all of the acidic sites and all of the basic sites.  

b. [3] Draw carefully placed arrows to show each point in the compound that can hydrogen bond to water.

c. [3]  Circle and name three (3) of its functional groups.

 

           

 

6. [8] Is it likely that exactly the same enzyme could completely hydrolyze both amylose and amylopectin ?  Explain your answer.

 

No. The branching in amylopectin is produced through 1--> 6 glycoside bonds. It is unlikely that an enzyme that  hyrolyzed 1-->4 bonds would also hydrolyze 1-->6 links.

 

7. Draw the structure of the major organic  products of each of the following reactions.

a. [5]

b. [5]

 

 

c. [5]

 

 

 

8. [6] a.  Draw the structures of . . .

 

methyl benzoate

 

 

sodium benzoate

 

      b. Compare the 2 compounds you just drew.

      1. [4]  Which will be more soluble in water? sodium benzoate Why?  Ions form strong bonds wih water so they are hydrophilic.

 

 

 

 

 

 

 

      2. [4]  At room temperature one is a solid & the other a liquid. Which is which? Why?         Sodium benzoate is the solid because it’s a salt. The oppositely charged ions in a salt are strongly attracted to each other                                                                                      

 

 

9.a. [6]   Draw a clear structural formula of any glycoside.

 

 

 

 

b. [6]  Will the compound you drew be reducing or nonreducing. Explain why.

Could be either depending on what you drew.

 

 

 

 

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