ORGANIC CHEMISTRY(LL)-W/ACCESS >CUSTOM<
10th Edition
ISBN: 9781259917196
Author: Carey
Publisher: MCG CUSTOM
expand_more
expand_more
format_list_bulleted
Question
Chapter 26, Problem 44P
Interpretation Introduction
Interpretation:
(a) The mechanism using curved arrows to show the flow of electrons is to be suggested for the given cyclization reaction.
(b) A stepwise mechanism is to be written for the hydrolysis of the conjugate acid of the iminolactone to corresponding lactone that cleaves the peptide chain.
Concept Introduction:
Cyanogen bromide adds to the sulfur atom of the methionine residue forming a sulfonium ion.
The sulfonium ion cyclizes to form an iminolactone.
Iminolactone undergoes hydrolysis, cleaving the bond between nitrogen and the ring carbon. This results in the peptide chain being cleaved between carbonyl of the methionine residue and the next amino acid.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Using the information below, determine the amino acid sequence of the peptide, and explain how your structure is consistent with each piece of information.
Complete hydrolysis by 6 M HCl at 110°C followed by amino acid analysis indicated the presence of Gly, Leu, Phe, and Tyr in a 2:1:1:1 molar ratio.
Treatment of the peptide with1-fluoro-2,4-dinitrobenzene followed by complete hydrolysis and chromatography indicated the presence of the 2,4-dinitrophenyl derivative of tyrosine. No free tyrosine could be found.
Complete digestion of he peptide with pepsin (which cleaves on the amino side of aromatic residues) followed by chromatography yielded a dipeptide containing Phe and Leu and a tripeptide containing Tyr and Gly in a 1:2 ratio.
An amino acid mixture of phenylalanine, glycine and glutamic acid is to be separated bypaper chromatography. The solvent is less polar than water. Which of these amino acids will have the highest Rf value and which the lowest? Explain.
Treatment of a new protein with dansyl chloride reveals two (2) dansyl-labelled derivatives of amino acids, alanine and methionine. What can you deduce about the structure of the protein from these results?
Name the amino acids that contribute atoms to both purine and pyrimidine rings.
An unknown decapeptide was isolated and characterized. Complete hydrolysis of this peptide gave : F(2), A,G,C,K,N,T, W and V. Treatment with carboxypeptidase releases A. Reaction with Edman’s reagent gave PTH-T and a nonapeptide. The nonapeptide was treated with trypsin and gave 2 peptides: (V-C-G-A) and (N-FF-W-K). Give the sequence of amino acid in the decapeptide.
Chapter 26 Solutions
ORGANIC CHEMISTRY(LL)-W/ACCESS >CUSTOM<
Ch. 26.1 - Prob. 1PCh. 26.2 - Prob. 2PCh. 26.2 - Prob. 3PCh. 26.3 - Prob. 4PCh. 26.3 - Prob. 5PCh. 26.4 - Prob. 6PCh. 26.4 - Prob. 7PCh. 26.4 - Prob. 8PCh. 26.5 - Prob. 9PCh. 26.6 - Prob. 10P
Ch. 26.6 - Prob. 11PCh. 26.6 - Prob. 12PCh. 26.7 - Prob. 13PCh. 26.7 - Prob. 14PCh. 26.7 - Prob. 15PCh. 26.7 - Prob. 16PCh. 26.7 - Prob. 17PCh. 26.9 - Prob. 18PCh. 26.10 - Digestion of the tetrapeptide of Problem 26.18...Ch. 26.12 - Prob. 20PCh. 26.12 - Prob. 21PCh. 26.15 - Prob. 22PCh. 26.15 - Prob. 23PCh. 26.16 - Prob. 24PCh. 26.17 - Prob. 25PCh. 26.18 - Prob. 26PCh. 26 - Prob. 27PCh. 26 - Prob. 28PCh. 26 - Prob. 29PCh. 26 - Prob. 30PCh. 26 - Prob. 31PCh. 26 - Prob. 32PCh. 26 - Prob. 33PCh. 26 - Prob. 34PCh. 26 - Prob. 35PCh. 26 - Prob. 36PCh. 26 - Prob. 37PCh. 26 - Prob. 38PCh. 26 - Prob. 39PCh. 26 - Prob. 40PCh. 26 - If you synthesized the tripeptide Leu-Phe-Ser from...Ch. 26 - Prob. 42PCh. 26 - Prob. 43PCh. 26 - Prob. 44PCh. 26 - Prob. 45DSPCh. 26 - Prob. 46DSPCh. 26 - Prob. 47DSPCh. 26 - Prob. 48DSPCh. 26 - Prob. 49DSPCh. 26 - Prob. 50DSP
Knowledge Booster
Similar questions
- Electrophoresis of a mixture of lysine, histidine, and cysteine is carried out at pH 7.64. Describe the behavior of each amino acid under these conditions.arrow_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 H2 receptors. In the development of this drug, a cyano group was added to the substituted guanidino 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.arrow_forwardGive the amino acid sequence of hexapeptides that produce the following sets of fragments upon partial acid hydrolysis: (a) Arg, Gly, Ile, Leu, Pro, Val gives Pro-Leu-Gly, Arg-Pro, Gly-Ile-Val (a) N, L, M, W, V2 gives V-L, V-M-W, W-N-Varrow_forward
- Write out the steps needed to synthesize the following peptide using the Merrifield method.arrow_forwardSomatostatin is a tetradecapeptide of the hypothalamus that inhibits the release of pituitary growth hormone. Its amino acid sequence has been determined by a combination of Edman degradations and enzymic hydrolysis experiments. On the basis of the following data, deduce the primary structure of somatostatin: 1. Edman degradation gave PTH-Ala. 2. Selective hydrolysis gave peptides having the following indicated sequences: Phe-Trp Thr-Ser-Cys Lys-Thr-Phe Thr-Phe-Thr-Ser-Cys Asn-Phe-Phe-Trp-Lys Ala-Gly-Cys-Lys-Asn-Phe 3. Somatostatin has a disulfide bridge.arrow_forwardDraw the structure of the tetrapeptide Asp-Arg-Val-Tyr. Please show the appropriate stereochemistry of the natural amino acids in the resulting peptide. Please draw all ionizable groups in their neutral form.arrow_forward
- According to the paper, F486 is a phenylalanine residue (i.e., an amino acid that is part of a chain that forms a protein) on SARS-CoV-2. It has an important interaction with ACE2 (best seen in Fig. 1(C) and Fig. 2(A)). Looking at this phenylalanine and the green residues surrounding it, which statement best describes the interaction that could be occurring? a) It forms a hydrogen bond with Y83. b) It forms a dipole-dipole interaction with M82. c) It forms London dispersion forces with surrounding residues. d) It encounters repulsions from surrounding residues.arrow_forwardBy using only amide/Peptide bond forming rxn and a lKylation rxns. Provide all the reaction steps with the reagent needed and conditions with out showing the mechanism for each step to form the product. Note: Use protecting groups like (Boc, Fmoc, and others) H2NNH2+arrow_forwardDetermine the primary structure of an octapeptide from the following data: Acid-catalyzed hydrolysis gives 2 Arg, Leu, Lys, Met, Phe, Ser, and Tyr. Carboxypeptidase A releases Ser. Edman’s reagent releases Leu. Treatment with cyanogen bromide forms two peptides with the following amino acid compositions: 1. Arg, Phe, Ser 2. Arg, Leu, Lys, Met, Tyr Trypsin-catalyzed hydrolysis forms the following two amino acids and two peptides: 1. Arg 2. Ser 3. Arg, Met, Phe 4. Leu, Lys, Tyrarrow_forward
- Determine the amino acid sequence of a polypeptide from the following data: Acid-catalyzed hydrolysis gives Ala, Arg, His, 2 Lys, Leu, 2 Met, Pro, 2 Ser, Thr, and Val. Carboxypeptidase A releases Val. Edman’s reagent releases PTH-Leu. Treatment with cyanogen bromide gives three peptides with the following amino acid compositions: 1. His, Lys, Met, Pro, Ser 2. Thr, Val 3. Ala, Arg, Leu, Lys, Met, Ser Trypsin-catalyzed hydrolysis gives three peptides and a single amino acid: 1. Arg, Leu, Ser 2. Met, Pro, Ser, Thr, Val 3. Lys 4. Ala, His, Lys, Metarrow_forwardDetermine the amino acid sequence of a polypeptide from the following data:Acid-catalyzed hydrolysis gives Ala, Arg, His, 2 Lys, Leu, 2 Met, Pro, 2 Ser, Thr, and Val.Carboxypeptidase A releases Val.Edman’s reagent releases PTH-Leu.Treatment with cyanogen bromide gives three peptides with the following amino acid compositions:1. His, Lys, Met, Pro, Ser 2. Thr, Val 3. Ala, Arg, Leu, Lys, Met, Serarrow_forwardThe reaction of ninhydrin with an -amino acid occurs in several steps (a) The first step is loss of water to give a triketone. Show the mechanism of the reaction and the structure of the triketone.(b) The second step is formation of an imine by reaction of the amino acid with the triketone. Show its structure. (c) The third step is a decarboxylation. Show the structure of the product and the mechanism of the decarboxylation reaction. (d) The fourth step is hydrolysis of an imine to yield an amine and an aldehyde. Show the structures of both products. (e) The final step is formation of the purple anion. Show the mechanism of the reactionarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning