Organic Chemistry
8th Edition
ISBN: 9781305580350
Author: William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher: Cengage Learning
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Chapter 27, Problem 27.51P
Interpretation Introduction
Interpretation:
In Merrifield solid phase peptide synthesis, the amino group is protected by fluorenylmethoxycarbonyl group (FMOC). The deprotection of the amino group is done by treatment with weak base such as secondary
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Ethyleneimine reacts with cysteine side chains in proteins to form S - aminoethyl derivatives. The peptide bonds on the carboxyl side of these modified cysteine residues are susceptible to hydrolysis by trypsin . Why?
Para-aminobenzoic acid has two ionizable groups. One is a
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The pk of the carboxylic acid is 4.9 and the pk of the
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N-
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A.
B.
O-H
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H
D.
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H
pK₂ = 4.9
Determine the amino acid sequence of a polypeptide from the following data: Complete hydrolysis of the peptide yields Arg, 2 Gly, Ile, 3 Leu, 2 Lys, 2 Met, 2 Phe, Pro, Ser, 2 Tyr, and Val. Treatment with Edman’s reagent releases PTH-Gly. Carboxypeptidase A releases Phe. Treatment with cyanogen bromide yields the following three peptides: 1. Gly-Leu-Tyr-Phe-Lys-Ser-Met 2. Gly-Leu-Tyr-Lys-Val-Ile-Arg-Met 3. Leu-Pro-Phe Treatment with trypsin yields the following four peptides: 1. Gly-Leu-Tyr-Phe-Lys 3. Val-Ile-Arg 2. Ser-Met-Gly-Leu-Tyr-Lys 4. Met-Leu-Pro-Phe
Chapter 27 Solutions
Organic Chemistry
Ch. 27.1 - Of the 20 protein-derived amino acids shown in...Ch. 27.2 - Prob. 27.2PCh. 27.2 - Prob. 27.3PCh. 27.3 - Draw a structural formula for Lys-Phe-Ala. Label...Ch. 27.4 - Which of these tripeptides are hydrolyzed by...Ch. 27.4 - Deduce the amino acid sequence of an undecapeptide...Ch. 27.6 - Prob. 27.7PCh. 27 - What amino acid does each abbreviation stand for?...Ch. 27 - The configuration of the chiral center in -amino...Ch. 27 - Assign an R or S configuration to the chiral...
Ch. 27 - Prob. 27.11PCh. 27 - Prob. 27.12PCh. 27 - Draw zwitterion forms of these amino acids. (a)...Ch. 27 - Prob. 27.14PCh. 27 - Why is Arg often referred to as a basic amino...Ch. 27 - Prob. 27.16PCh. 27 - Prob. 27.17PCh. 27 - Prob. 27.18PCh. 27 - Prob. 27.19PCh. 27 - Prob. 27.20PCh. 27 - Both norepinephrine and epinephrine are...Ch. 27 - Prob. 27.22PCh. 27 - Draw a structural formula for the form of each...Ch. 27 - Prob. 27.24PCh. 27 - Write the zwitterion form of alanine and show its...Ch. 27 - Prob. 27.26PCh. 27 - Write the form of aspartic acid most prevalent at...Ch. 27 - Prob. 27.28PCh. 27 - Prob. 27.29PCh. 27 - For lysine and arginine, the isoelectric point,...Ch. 27 - Prob. 27.31PCh. 27 - Account for the fact that the isoelectric point of...Ch. 27 - Prob. 27.33PCh. 27 - Prob. 27.34PCh. 27 - At pH 7.4, the pH of blood plasma, do the majority...Ch. 27 - Prob. 27.36PCh. 27 - Prob. 27.37PCh. 27 - Prob. 27.38PCh. 27 - A chemically modified guanidino group is present...Ch. 27 - Draw a structural formula for the product formed...Ch. 27 - Prob. 27.41PCh. 27 - Prob. 27.42PCh. 27 - A decapeptide has the following amino acid...Ch. 27 - Following is the primary structure of glucagon, a...Ch. 27 - Prob. 27.45PCh. 27 - Draw a structural formula of these tripeptides....Ch. 27 - Estimate the pI of each tripeptide in Problem...Ch. 27 - Glutathione (G-SH), one of the most common...Ch. 27 - Following are a structural formula and a...Ch. 27 - Prob. 27.50PCh. 27 - Prob. 27.51PCh. 27 - Prob. 27.52PCh. 27 - Prob. 27.53PCh. 27 - Prob. 27.54PCh. 27 - Distinguish between intermolecular and...Ch. 27 - Prob. 27.56PCh. 27 - Prob. 27.57P
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- Determine the amino acid sequence of a polypeptide from the following data:Complete hydrolysis of the peptide yields Arg, 2 Gly, Ile, 3 Leu, 2 Lys, 2 Met, 2 Phe, Pro, Ser, 2 Tyr, and Val.Treatment with Edman’s reagent releases PTH-Gly.Carboxypeptidase A releases Phe. Treatment with cyanogen bromide yields the following three peptides:1. Gly-Leu-Tyr-Phe-Lys-Ser-Met 2. Gly-Leu-Tyr-Lys-Val-Ile-Arg-Met 3. Leu-Pro-Phearrow_forwardA chemically modified guanidino group is present in cimetidine (Tagamet), a widely prescribed drug for the control of gastric acidity and peptic ulcers. Cimetidine reduces gastric acid secretion by inhibiting the interaction of histamine with gastric H, recep- tors. In the development of this drug, a cyano group was added to the substituted gua- nidino group to alter its basicity. Do you expect this modified guanidino group to be more basic or less basic than the guanidino group of arginine? Explain. N-CN H,C CH,SCH,CH,NHËNHCH, HN, Cimetidine (Tagamet)arrow_forwardThere are 20 common, naturally occurring amino acids from which all proteins are derived (as will be discussed in Chapter 25), although many other less common amino acids have been isolated from natural sources. Valine is one of the 20 common amino acids, and it was used as a starting material in the laboratory synthesis of an uncommon amino acid (Tetrahedron 1997, 53, 1151-1156). During one of the steps in the synthesis, compound 1 was treated with HBr under conditions that favor radical addition, giving stereoisomers 2 and 3. Draw the structures of 2 and 3, and describe their stereoisomeric relationship. H. LOCH3 HBr 2 + 3 hv H (S)-valine Modify the given copies of compound 1 to drawthe structures of 2 and 3. You can use the single bond tool to add/remove double bonds. CH2 CH2 H,C- H3C- -CH, -CH, Edit Drawing Describe the relationship of 2 and 3. O They are enantiomers. O They are superimposable. They are diastereomers. O They are constitutional isomers.arrow_forward
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