Concept explainers
(a)
To determine: The product formed by the reaction of trityl chloride with nucleoside on the
Interpretation: The product formed by the reaction of trityl chloride with nucleoside on the
Concept introduction: Protecting group is a species that undergoes chemical modification so that chemoselectivity can be introduced in the
(b)
To determine: An explanation corresponding to the selectivity of trityl derivative for the
Interpretation: An explanation corresponding to the selectivity of trityl derivative for the
Concept introduction: Protecting group is a species that undergoes chemical modification so that chemoselectivity can be introduced in the chemical reaction.
(c)
To determine: An explanation corresponding to the removal of DMT group under dilute acid conditions and instant turning of solution to orange color when acid is added to a DMT derivative.
Interpretation: An explanation corresponding to the removal of DMT group under dilute acid conditions and instant turning of solution to orange color when acid is added to a DMT derivative is to be stated.
Concept introduction: Protecting group is a species that undergoes chemical modification so that chemoselectivity can be introduced in the chemical reaction.
Want to see the full answer?
Check out a sample textbook solutionChapter 23 Solutions
Organic Chemistry (9th Edition)
- Most of the ultraviolet absorption of proteins at 280 nm is due to their content of a. Glutamate b. Tryptophan c. Alanine d. Aspartatearrow_forward4) Paxlovid is treatment for COVID-19 that was recently approved for use because it can drastically reduce the risk for hospitalization and death when taken early in the infection. It is actually a package of two different antiviral drugs. One of those is Nirmatrelvir, which is a modified tripeptide protein mimetic designed to covalently bind to and inhibit the main protease (MPro) from the SARS-CoV-2 virus. This protease recognizes and hydrolyzes peptide bonds at specific points in their sequence, and it is essential for viral replication. a. Below is one of the sequences that Mpro recognizes and cleaves. It cleaves the peptide bond between the glutamine and the glycine. Draw out the structure of a peptide with this sequence, including the appropriate stereochemistry for biological amino acids and assuming the peptide is at physiological pH (pH = 7.4). SGVTFQGKF b. What would the net charge of the peptide be at physiological pH?. c. At what pH would the peptide be net neutral?arrow_forwardShown are the configuration of a gel electrophoresis experiment. Charged plates establish an electric field on a region of gel between the plates. A solution of DNA fragments, which acquire a negative charge in solution, is analyzed by using an electric field to drive the fragments through the gel. A drag force opposes the motion, causing the fragments to move at a constant speed. Larger fragments move more slowly, so the fragments separate by size to give a “fingerprint” of the sample. What is the energy transformation as the fragments move through the gel?A. Electric potential energy to kinetic energyB. Electric potential energy to thermal energyC. Electric potential energy to kinetic energy and thermal energyD. Kinetic energy to thermal energyarrow_forward
- 18. Draw the structure of the tripeptide Tyr-Gly-Lys as it exists at pH 13. and what if it was at an acidic pH?arrow_forward. Polyglycine, a simple polypeptide, can form a helix with 6 = -80°, ự = +150°. From the Ramachandran plot (see Figure 6.11), describe this helix with respect to (a) handedness and (b) number of residues per turn.arrow_forward. Describe the pH range of acceptable buffering behavior for the amino acids alanine, histidine, aspartic acid, and lysine.arrow_forward
- (CH21/23) [References] Draw the structure of the major organic product(s) of the reaction. H₂C 1. 2 CH3MgBr, ether 2. H₂O You do not have to consider stereochemistry. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate multiple products using the + sign from the drop-down menu. 89 ? ChemDoodle 424 [F Previous Next Save and Exitarrow_forwardThe DNA of bacteriophage lambda has 1.2 x 10^5 nucleotides. How many proteins of molecular weight 40,000 could be coded by this DNA? Assume a molecular weight of 100 for the average amino acid.arrow_forwardConsider the formation of a dimeric protein 2P ->P2 At 25.0 °C , the enthalpy of the reaction is 17 kj/mol and the entropy of the reaction is 65 j/kmol. Is the dimerization favored at this temperature ? Thermodynamically speaking, explain/support your answer. Show work.arrow_forward
- Please write the chemical reaction in fluorescence Riboflavin (Vitamin B2) + Acetic Acid C17H20N4O6 + CH3COOH----->arrow_forwardThe amino acid "arginine (Arg)" has the following form: Arg, HArg, H₂ Arg+, H3 Arg²+. Which is the second most prominent species at pH 6.0? pKa1 = 1.82, pKa2 = 8.99, pKa3 = 12.1arrow_forwardUnder the conditions of this extractive procedure, how does aspirin become partitioned into the aqueous layer? How do we then recover this substance in a pure form from the aqueous layer? O 1) The acidic hydrogen in the carboxyl group (-COOH) of aspirin undergoes an acid-base reaction with NaOH to form the conjugate base, sodium 2-acetoxybenzoate. U 2) This ionic species then readily dissolves in water. 3) Conversely, the organic unknown does not possess an acidic residue, so no acid/base reaction can occur. 4) It therefore does dissolve in water.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningIntroductory Chemistry: An Active Learning Approa...ChemistryISBN:9781305079250Author:Mark S. Cracolice, Ed PetersPublisher:Cengage LearningGeneral Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage Learning
- Introduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage LearningChemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage LearningChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage Learning