Problem 1b
Give the pKa value of the following compounds.
b.
Problem 2
Calculate the equilibrium constant for the reaction of ethylamine and propanoic acid. Which side is favored?
Problem 5
Although there is free rotation around most σ bonds, rotation is restricted around the C--N bond of an amide. Explain why this is true.
Problem 18b
Provide a synthesis of the following amino acids using a combination of the HVZ and amination reactions.
b. Leu
Problem 28
Provide a mechanism for the protection of the amine as the benzylcarbamate shown in Figure 26.33(a). <IMAGE>
Problem 32
Why are conjugated molecules like the product of the ninhydrin reaction brightly colored?
Problem 38
The first amino acid in the pentapeptide of Figure 26.50, Pyr, is not one of the 20 amino acids in Table 26.1. Based on the following structure of Pyr, from which natural amino acid is it likely derived?
Problem 46b
Draw the following amino acids in all possible protonation states as you move from high pH to low pH.
b. His
Problem 51a
Show how you would synthesize the following amino acids using the Strecker amino acid synthesis.
a. Ala
Ch. 26 - Amino Acids, Proteins, and Peptide Synthesis