OWLv2 with MindTap Reader, 1 term (6 months) Printed Access Card for Brown/Iverson/Anslyn/Foote's Organic Chemistry, 8th Edition
8th Edition
ISBN: 9781305582439
Author: Brown, William H.; Iverson, Brent L.; Anslyn, Eric; Foote, Christopher S.
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 3, Problem 3.24P
When oxaloacetic acid and acetyl-coenzyme A (acetyl-CoA) labeled with radioactive carbon-14 in position 2 are incubated with citrate synthase, an enzyme of the tricarboxylic acid cycle, only the following enantiomer of [2-l4C]citric acid is formed stereoselectively. Note that citric acid containing only 12C is achiral. Assign an R or S configuration to this enantiomer of [2-14C]citric acid. (Note: Carbon-14 has a higher priority than carbon-12.)
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
Clopidogrel is the generic name for Plavix, a drug used to prevent the formation of blood clots in patients that have a history of heart attacks or strokes. A single enantiomer of clopidogrel can be prepared in three steps from the chiral α-hydroxy acid A. Identify B and C in the following reaction sequence, and designate the configuration of the enantiomer formed by this route as R or S.
When oxaloacetic acid and acetyl-coenzyme A (acetyl-CoA) labeled with radioactive
carbon-14 in position 2 are incubated with citrate synthase, an enzyme of the tricarboxylic
acid cycle, only the following enantiomer of [2-14C]citric acid is formed stereoselectively.
Note that citric acid containing only 12C is achiral. Assign an R or S configuration to this
enantiomer of [2-14C]citric acid. (Note: Carbon-14 has a higher priority than carbon-12.)
C-COOH
14CH,COOH
citrate
synthase
ČH,COOH + 14CH,CSCOA
НООС
-COH
CH,COOH
Oxaloacetic acid
Acetyl-CoA
[2-14C]Citric acid
The following bicyclic ketone has two a-carbons and three a-hydrogens. When this molecule
is treated with D,O in the presence of an acid catalyst, only two of the three a-hydrogens
exchange with deuterium. The a-hydrogen at the bridgehead does not exchange.
H
these two a-hydrogens exchange
H.
this a-hydrogen
does not exchange
H
How do you account for the fact that two a-hydrogens do exchange but the third
does not? You will find it helpful to build models of the enols by which exchange of
a-hydrogens occurs.
Chapter 3 Solutions
OWLv2 with MindTap Reader, 1 term (6 months) Printed Access Card for Brown/Iverson/Anslyn/Foote's Organic Chemistry, 8th Edition
Ch. 3.2 - Prob. 3.1PCh. 3.3 - Assign priorities to the groups in each set. (a)...Ch. 3.3 - Prob. 3.3PCh. 3.4 - Following are stereorepresentations for the four...Ch. 3.4 - Prob. 3.5PCh. 3.4 - Prob. 3.6PCh. 3.5 - How many stereoisomers exist for...Ch. 3.5 - How many stereoisomers exist for...Ch. 3.7 - Prob. 3.9PCh. 3.7 - Prob. 3.10P
Ch. 3.8 - If the side chain of the amino add is a methyl...Ch. 3.8 - Prob. BQCh. 3.8 - The amino acids cysteine and serine are shown....Ch. 3.8 - Prob. DQCh. 3.8 - As stated, proteins are stereochemically pure...Ch. 3.8 - As stated, proteins are stereochemically pure...Ch. 3 - Prob. 3.11PCh. 3 - One reason we can be sure that sp3-hybridized...Ch. 3 - Which compounds contain chiral centers? (a)...Ch. 3 - Prob. 3.15PCh. 3 - Prob. 3.16PCh. 3 - Prob. 3.17PCh. 3 - Mark each chiral center in the following molecules...Ch. 3 - Prob. 3.19PCh. 3 - Assign priorities to the groups in each set. (a) H...Ch. 3 - Following are structural formulas for the...Ch. 3 - Following is a staggered conformation for one of...Ch. 3 - Prob. 3.23PCh. 3 - When oxaloacetic acid and acetyl-coenzyme A...Ch. 3 - Prob. 3.25PCh. 3 - Mark each chiral center in the following molecules...Ch. 3 - Prob. 3.27PCh. 3 - Prob. 3.28PCh. 3 - Prob. 3.29PCh. 3 - Prob. 3.30PCh. 3 - Which of the following are meso compounds?Ch. 3 - Prob. 3.32PCh. 3 - Prob. 3.33PCh. 3 - Which of the following compounds are chiral?...Ch. 3 - Prob. 3.35PCh. 3 - Prob. 3.36PCh. 3 - Prob. 3.37PCh. 3 - The chiral catalyst (R)-BINAP-Ru is used to...Ch. 3 - Prob. 3.39P
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- The first step in the metabolism of glycerol, formed by digestion of fats, is phosphorylation of the pro-R—CH2OH group by reaction with adenosine triphosphate (ATP) to give the corresponding glycerol phosphate plus adenosine diphosphate (ADP). Show the stereochemistry of the product.arrow_forwardTreatment of -D-glucose with methanol in the presence of an acid catalyst converts it into a mixture of two compounds called methyl glucosides (Section 25.3A). In these representations, the six-membered rings are drawn as planar hexagons. (a) Propose a mechanism for this conversion and account for the fact that only the OH on carbon 1 is transformed into an OCH3 group. (b) Draw the more stable chair conformation for each product. (c) Which of the two products has the chair conformation of greater stability? Explain.arrow_forwardFollowing is a retrosynthesis for the coronary vasodilator ganglefene. (a) Propose a synthesis for ganglefene from 4-hydroxybenzoic acid and 3-methyl-3-buten-2-one. (b) Is ganglefene chiral? If so, which of the possible stereoisomers are formed in this synthesis?arrow_forward
- The lactic acid that builds up in tired muscles is formed from pyruvate. If the reaction occurs with addition of hydrogen to the Re face of pyruvate, what is the stereochemistry of the product?arrow_forwardOne of the following molecules (a)–(d) is d-erythrose 4-phosphate, an intermediate in the Calvin photosynthetic cycle by which plants incorporate CO2 into carbohydrates. If d-erythrose 4-phosphate has R stereochemistry at both chirality centers, which of the structures is it? Which of the remaining three structures is the enantiomer of d-erythrose 4-phosphate, and which are diastereomers?arrow_forwardClopidogrel is the generic name for Plavix, a drug used to prevent the formation of blood clots in patients that have a history of heart attacks or strokes. A single enantiomer of clopidogrel can be prepared in three steps from the chiral αhydroxy acid A. Identify B and C in the following reaction sequence, and designate the conguration of the enantiomer formed by this route as R or S.arrow_forward
- Heating D-altrose with dilute acid produces a nonreducing anhydro sugar (C6H1005). Methylation of the anhydro sugar followed by acid hydrolysis yields 2,3,4-tri-O-methyl-D-altrose. The formation of the anhydro sugar takes place through a chair conformation of ẞ- D-altropyranose in which the -CH2OH group is axial. What is the structure of the anhydro sugar? CH3 OH HO OH I H₂C CH3 0. 0 H H H H HO OH OH I CH3 H₂C H H H H CH₂ -OH OH HO eTextbook and Media Explain how is it formed. The anhydro sugar is formed when the axial -CH2OH group reacts with C to form a cyclic SUPF Because the anhydro sugar is (i.e., an internal glycoside), it is a sugar. Methylation followed by acid hydrolysis converts the anhydro sugar to 2,3,4-tri-O-methyl-D-altrose.arrow_forwardWhen pure (S)-lactic acid is esterified by racemic butan-2-ol, the product is 2-butyl lactate, with the following structure:H+CH3 CH COOH CH3 CH CH3 CH CHOH OHCH2CH3 CH2CH3lactic acidC OOH CH O 3butan-2-ol 2-butyl lactate+(a) Draw three-dimensional structures of the two stereoisomers formed, specifying the configuration at each asymmetriccarbon atom. (Using your models may be helpful.)(b) Determine the relationship between the two stereoisomers you have drawnarrow_forward4. The enantiomer shown below is levorotatory. Draw the enantiomer which is dextrorotatory. CH3 H CO2H (R)-lactic acid 5. A solution containing 2.0g of compound dissolved in 50mL of solvent generated an observed rotation of plane-polarized light (A = 589.6nm) of 20° in a polarimeter tube 300mm long at a temperature of 25°C. What is the specific rotation of the compound? 6. How many asymmetric centers does the compound shown below have? CH3arrow_forward
- A chemist carried out the following reaction with a single enantiomer of the starting compound. The product was found to be optically inactive. Which of these explanations is correct? You may select more than one answer. : SCH, : ȘCH, + но HO Br :Br: :ÓH O The reaction proceeds via an intermediate that is not chiral. O The product is optically inactive because it is a meso compound. O The product is optically inactive because it does not contain any asymmetric centers. O The starting material could have racemized before the reaction occurred.arrow_forwardWhat product is formed when the esters in ginkgolide B, the chapter-opening molecule, are hydrolyzed in aqueous acid? Indicate the stereochemistry of all stereogenic centers.arrow_forwardDraw all of the possible stereoisomers of the compound shown. Group them as enantiomeric pairs, or indicate any meso compounds. Label all stereocenters with the absolute stereochemistry (R or S).arrow_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
Enzymes - Effect of cofactors on enzyme; Author: Tutorials Point (India) Ltd;https://www.youtube.com/watch?v=AkAbIwxyUs4;License: Standard YouTube License, CC-BY
Enzyme Catalysis Part-I; Author: NPTEL-NOC IITM;https://www.youtube.com/watch?v=aZE740JWZuQ;License: Standard Youtube License