Organic Chemistry
7th Edition
ISBN: 9780321803221
Author: Paula Y. Bruice
Publisher: Prentice Hall
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Textbook Question
Chapter 22, Problem 72P
Propose a mechanism for the rearrangement of the thiazoline obtained from the reaction of Ed man's reagent with a peptide to a PTH-amino acid (page 1014). (Hint: Thioesters are very reactive toward nucleophiles.)
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Chapter 22 Solutions
Organic Chemistry
Ch. 22.1 - a. Explain why, when the imidazole ring of...Ch. 22.2 - a. Which isomer(R)-alanine or (S)-alanineis...Ch. 22.2 - Prob. 4PCh. 22.3 - Prob. 5PCh. 22.3 - Prob. 6PCh. 22.3 - Draw the predominant form for glutamate in a...Ch. 22.3 - a. Why is the pKa of the glutamate side chain...Ch. 22.4 - Explain why the pI of lysine is the average of the...Ch. 22.4 - Calculate the pI of each of the following amino...Ch. 22.4 - a. Which amino acid has the lowest pI value? b....
Ch. 22.4 - Prob. 13PCh. 22.5 - What aldehyde is formed when valine is treated...Ch. 22.5 - Prob. 15PCh. 22.5 - Prob. 16PCh. 22.5 - Prob. 17PCh. 22.5 - Prob. 18PCh. 22.6 - Why is excess ammonia used in the preceding...Ch. 22.6 - Prob. 20PCh. 22.6 - What amino acid is formed using the...Ch. 22.6 - Prob. 22PCh. 22.6 - What amino acid is formed when the aldehyde used...Ch. 22.7 - Esterase is an enzyme that catalyzes the...Ch. 22.8 - Draw the tetrapeptide Ala-Thr-Asp-Asn and indicate...Ch. 22.8 - Prob. 26PCh. 22.8 - Prob. 27PCh. 22.8 - Which bonds in the backbone of a peptide can...Ch. 22.9 - What is the configuration about each of the...Ch. 22.9 - Glutathione is a tripeptide whose function is to...Ch. 22.10 - What dipeptides would be formed by heating a...Ch. 22.10 - Suppose you are trying to synthesize the dipeptide...Ch. 22.10 - Show the steps in the synthesis of the...Ch. 22.10 - a. Calculate the overall yield of bradykinin when...Ch. 22.11 - Show the steps in the synthesis of the...Ch. 22.13 - Prob. 36PCh. 22.13 - In determining the primary structure of insulin,...Ch. 22.13 - A decapeptide undergoes partial hydrolysis to give...Ch. 22.13 - Explain why cyanogen bromide does not cleave on...Ch. 22.13 - Indicate the peptides produced from cleavage by...Ch. 22.13 - Prob. 42PCh. 22.13 - Three peptides were obtained from a trypsin...Ch. 22.14 - Prob. 44PCh. 22.15 - How would a protein that resides in the nonpolar...Ch. 22.16 - a. Which would have the greatest percentage of...Ch. 22 - Prob. 47PCh. 22 - Glycine has pK2 values of 2.34 and 9.60. At what...Ch. 22 - Prob. 49PCh. 22 - Prob. 50PCh. 22 - Aspartame (its structure is on page 1007) has a pl...Ch. 22 - Draw the form of aspartate that predominates at...Ch. 22 - A professor was preparing a manuscript for...Ch. 22 - Prob. 54PCh. 22 - Determine the amino acid sequence of a polypeptide...Ch. 22 - Prob. 56PCh. 22 - Which is the more effective buffer at...Ch. 22 - Identify the location and type of charge on the...Ch. 22 - Draw the product obtained when a lysine side chain...Ch. 22 - After the polypeptide shown below was treated with...Ch. 22 - Treatment of a polypeptide with 2-mercaptoethanol...Ch. 22 - Show how aspartame can be synthesized using DCCD.Ch. 22 - -Amino acids can be prepared by treating an...Ch. 22 - Reaction of a polypeptide with carboxypeptidase A...Ch. 22 - a. How many different octapeptides can be made...Ch. 22 - Glycine has pKa values of 2.3 and 9.6. Do you...Ch. 22 - A mixture of 15 amino acids gave the fingerprint...Ch. 22 - Write the mechanism for the reaction of an amino...Ch. 22 - Prob. 69PCh. 22 - Show how valine can be prepared by a. a...Ch. 22 - A chemist wanted to test his hypothesis that the...Ch. 22 - Propose a mechanism for the rearrangement of the...Ch. 22 - A normal polypeptide and a mutant of the...Ch. 22 - Determine the amino acid sequence of a polypeptide...
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