Organic Chemistry (9th Edition)
9th Edition
ISBN: 9780321971371
Author: Leroy G. Wade, Jan W. Simek
Publisher: PEARSON
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Chapter 24, Problem 24.44SP
Complete hydrolysis of an unknown basic decapeptide gives Gly, Ala, Leu, IIe, Phe, Tyr, Glu, Arg, Lys, and Ser. Terminal residue analysis shows that the N terminus is Ala and the C terminus is lle. Incubation of the decapeptide with chymotrypsin gives two tripeptides, A and B, and a tetrapeptide, C. Amino acid analysis shows that peptide A contains Gly, Glu, Tyr, and NH3; peptide B contains Ala, Phe, and Lys, and peptide C contains Leu, lle, Ser, and Arg. Terminal residue analysis gives the following results.
| N terminus | C terminus | |
| A | Gln | Tyr |
| B | Ala | Phe |
| C | Arg | Ile |
Incubation of the decapeptide with trypsin gives a dipeptide D, a pentapeptide E, and a tripeptide F. Terminal residue analysis of F shows that the N terminus is Ser and the C terminus is Iie. Propose a structure for the decapeptide and for fragments A through F.
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Chapter 24 Solutions
Organic Chemistry (9th Edition)
Ch. 24.2A - Draw three-dimensional representations of the...Ch. 24.2A - Prob. 24.2PCh. 24.2B - The herbicide glyphosate (Roundup) kills plants by...Ch. 24.4 - Draw the structure of the predominant form of a....Ch. 24.4 - Draw the resonance forms of a protonated guanidino...Ch. 24.4 - Although tryptophan contains a heterocyclic amine,...Ch. 24.4 - Prob. 24.7PCh. 24.4 - Prob. 24.8PCh. 24.5A - Show how the following amino acids might be formed...Ch. 24.5B - Prob. 24.10P
Ch. 24.5C - Prob. 24.11PCh. 24.5C - Show how you would use a Strecker synthesis to...Ch. 24.6 - Suggest how you would separate the free i-ammo...Ch. 24.7A - Propose a mechanism for the acid-catalyzed...Ch. 24.7A - Give equations for the formation and...Ch. 24.7B - Prob. 24.16PCh. 24.7C - Prob. 24.17PCh. 24.8B - Draw the complete structures of the following...Ch. 24.9C - Prob. 24.19PCh. 24.9C - Prob. 24.20PCh. 24.9C - Prob. 24.21PCh. 24.9E - Prob. 24.22PCh. 24.9E - Prob. 24.23PCh. 24.10A - Propose a mechanism for the coupling of acetic...Ch. 24.10B - Show how you would synthesize Leu-Gly-Ala-Val-Phe...Ch. 24.10B - Show how solid-phase peptide synthesis would be...Ch. 24 - a. The isoelectric point (pl) of phenylalanine is...Ch. 24 - Prob. 24.28SPCh. 24 - Prob. 24.29SPCh. 24 - Prob. 24.30SPCh. 24 - Prob. 24.31SPCh. 24 - Suggest a method for the synthesis of the...Ch. 24 - Prob. 24.33SPCh. 24 - Write the complete structures for the following...Ch. 24 - The following structure is drawn in an...Ch. 24 - Prob. 24.36SPCh. 24 - Prob. 24.37SPCh. 24 - Show the steps and intermediates in the synthesis...Ch. 24 - Prob. 24.39SPCh. 24 - Lipoic acid is often found near the active sites...Ch. 24 - Prob. 24.41SPCh. 24 - Prob. 24.42SPCh. 24 - Prob. 24.43SPCh. 24 - Complete hydrolysis of an unknown basic...Ch. 24 - Prob. 24.45SPCh. 24 - Prob. 24.46SPCh. 24 - Prob. 24.47SP
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