Problem Set 1: Amino Acids and Peptide Synthesis (15 pts)

Problem Set 1: Amino Acids and Peptide Synthesis (15 pts) Name:_________________________
Multiple Choice: Place your answer in the box provided. (0.5 pt each)
1. Which of the following amino acids is NOT classified as non-polar?
a. tryptophan
b. methionine
c. valine
d. serine

2. Which of the following statements is true regarding peptides?
a. Peptide sequences are written from C-terminus to N-terminus.
b. Peptides are synthesized in the body from C-terminus to N-terminus.
c. The amides in the peptide backbone prefer the cis conformation.
d. The amides in the peptide backbone are planar.

3. Which of the following amino acid protecting groups is NOT removed with strong acid?
a. Boc
b. t-butyl
c. trityl
d. alloc

4. Which reason below best describes why an orthogonal protecting group strategy is used during peptide synthesis?
a. To prevent amino acid side chain reactivity while allowing synthesis to continue on the N-terminus.
b. To limit the amount of epimerization that occurs.
c. To activate the C-terminal carboxylic acid for amide bond formation.
d. To confirm that a reaction worked through the observation of a purple color.

5. Provide the complete structure for each of the amino acids below. (6 pts)
a. Fmoc-Tyr(Trt)-OH

b. H-Lys(Cbz)-OtBu

c. Boc-Asp(Alloc)-OH

6. Write the complete short-hand notation for the amino acids below. (3 pts)
a.

___________________________________________

b.

___________________________________________

7. Write the sequence for the peptide below using three letter codes. (2 pts)

8. Write the sequence for the peptide below using single letter codes. (2 pts)

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Set 1 of Problems: Amino Acids and Peptide Synthesis (15 pts) Name:_________________________
Fill in the blanks with your answer to the multiple-choice question. (each worth 0.5 point)

1. Which of the following amino acids is NOT a non-polar amino acid?

a. tryptophan

b. methionine
q
c. valine

d. serine

2. Which of the following claims about peptides is correct?

a. Peptide sequences are written in the order C-terminus-N-terminus.

b. In the body, peptides are produced from the C-terminus to the N-terminus.

c. Peptide backbone amides favor the cis conformation.

d. The planar amides in the peptide backbone.

3. Which of the following amino acid protecting groups does not dissolve in strong acid?

a. Boc

b. t-butyl

c. trityl

d. alloc

4. Which of the following reasons best depicts why an orthogonal