Organic Chemistry
5th Edition
ISBN: 9780078021558
Author: Janice Gorzynski Smith Dr.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 29, Problem 29.38P
a. Draw the structure of the tripeptide A–A–A, and label the two ionizable
b. What is the predominant form of A–A–A at
c. The pKa values for the two ionizable functional groups (3.39 and 8.03) differ considerably from the pKa values of alanine (2.35 and 9.87; see Table 29.1). Account for the observed pKa differences.
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The peptide KNYPEH N-terminal amino group has a pKa of 8.6 and the C-terminal carboxylate group has a pKa of 4.5. What is the net charge of this peptide at a pH of 1?
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The peptide KNYPEH N-terminal amino group has a pKa of 8.6 and the C-terminal carboxylate group has a pKa of 4.5. What is the net charge of this peptide at a pH of 7?
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The peptide KNYPEH N-terminal amino group has a pKa of 8.6 and the C-terminal carboxylate group has a pKa of 4.5. What is the net charge of this peptide at a pH of 15?
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The peptide KNYPEH N-terminal amino group has a pKa of 8.6 and the C-terminal carboxylate group has a pKa of 4.5. What is the isoelectric point of this peptide?
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DU
Explain why the pKa of the - NH3+ group of an a-amino acid is lower than the pKa of the ammonium ion derived from a 1° amine (RNH3+). For example the pKa of the - NH3+ group of alanine is 9.87 but the pKa of CH3NH3+ is 10.63.
Chapter 29 Solutions
Organic Chemistry
Ch. 29 - Prob. 29.1PCh. 29 - Problem 29.2
What form exists at the isoelectric...Ch. 29 - Problem 29.3
Explain why the of the group of an...Ch. 29 - Prob. 29.4PCh. 29 - Problem 29.5
What -halo carbonyl compound is...Ch. 29 - Problem 29.6
The enolate derived from diethyl...Ch. 29 - Problem 29.7
What amino acid is formed when is...Ch. 29 - Problem 29.8
What aldehyde is needed to synthesize...Ch. 29 - Problem 29.9
Draw the products of each...Ch. 29 - Prob. 29.10P
Ch. 29 - Prob. 29.11PCh. 29 - Prob. 29.12PCh. 29 - Problem 29.13
What alkene is needed to synthesize...Ch. 29 - Problem 29.14
Draw the structure of each peptide....Ch. 29 - Problem 29.15
Name each peptide using both the...Ch. 29 - Prob. 29.16PCh. 29 - Prob. 29.17PCh. 29 - Problem 29.18
Glutathione, a powerful antioxidant...Ch. 29 - Problem 29.19
Draw the structure of the...Ch. 29 - Problem 29.20
Give the amino acid sequence of an...Ch. 29 - a What products are formed when each peptide is...Ch. 29 - Prob. 29.22PCh. 29 - Devise a synthesis of each peptide from amino acid...Ch. 29 - Devise a synthesis of the following dipeptide from...Ch. 29 - Prob. 29.25PCh. 29 - Consider two molecules of a tetrapeptide composed...Ch. 29 - What types of stabilizing interactions exist...Ch. 29 - Prob. 29.28PCh. 29 - Draw the product formed when the following amino...Ch. 29 - With reference to the following peptide: a...Ch. 29 - Devise a synthesis of the following dipeptide from...Ch. 29 - Prob. 29.32PCh. 29 - Histidine is classified as a basic amino acid...Ch. 29 - Tryptophan is not classified as a basic amino acid...Ch. 29 - What is the structure of each amino acid at its...Ch. 29 - What is the predominant form of each of the...Ch. 29 - 29.37 What is the predominant form of each of the...Ch. 29 - a. Draw the structure of the tripeptide A–A–A, and...Ch. 29 - 29.39 Draw the organic products formed in each...Ch. 29 - 29.40 What alkyl halide is needed to synthesize...Ch. 29 - 29.41 Devise a synthesis of threonine from diethyl...Ch. 29 - 29.42 Devise a synthesis of each amino acid from...Ch. 29 - Prob. 29.43PCh. 29 - Prob. 29.44PCh. 29 - Prob. 29.45PCh. 29 - Prob. 29.46PCh. 29 - Prob. 29.47PCh. 29 - 29.48 Brucine is a poisonous alkaloid obtained...Ch. 29 - Prob. 29.49PCh. 29 - Prob. 29.50PCh. 29 - Draw the structure for each peptide: (a) Phe–Ala;...Ch. 29 - 29.52 For the tetrapeptide Asp–Arg–Val–Tyr:
a....Ch. 29 - Prob. 29.53PCh. 29 - Prob. 29.54PCh. 29 - 29.55 Draw the amino acids and peptide fragments...Ch. 29 - Prob. 29.56PCh. 29 - Prob. 29.57PCh. 29 - Prob. 29.58PCh. 29 - 29.59 An octapeptide contains the following amino...Ch. 29 - 29.60 Draw the organic products formed in each...Ch. 29 - Draw all the steps in the synthesis of each...Ch. 29 - 29.62 Write out the steps for the synthesis of...Ch. 29 - 29.63 Besides the Boc and Fmoc protecting groups...Ch. 29 - 29.64 Another method to form a peptide bond...Ch. 29 - 29.65 Draw the mechanism for the reaction that...Ch. 29 - 29.66 Which of the following amino acids are...Ch. 29 - 29.67 After the peptide chain of collagen has been...Ch. 29 - Prob. 29.68PCh. 29 - Prob. 29.69PCh. 29 - 29.70 The anti-obesity drug orlistat works by...Ch. 29 - Prob. 29.71P
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