Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Chapter 29.SE, Problem 24MP
One of the steps in the pentose phosphate pathway for glucose catabolism is the reaction of xylulose 5-phosphate with ribose 5-phosphate in the presence of a transketolase to give glyceraldehyde 3-phosphate and sedoheptulose 7-phosphate.
(a) The first part of the reaction is nucleophilic addition of thiamin diphosphate (TPP) ylide to xylulose 5-phosphate, followed by a retro-aldol cleavage to give glyceraldehyde 3-phosphate and a TPPcontaining enamine. Show the structure of the enamine and the mechanism by which it is formed.
(b) The second part of the reaction is addition of the enamine to ribose 5-phosphate followed by loss of TPP ylide to give sedoheptulose 7-phosphate. Show the mechanism.
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Chapter 29 Solutions
Organic Chemistry
Ch. 29.1 - Prob. 1PCh. 29.3 - Write the equations for the remaining passages of...Ch. 29.3 - Prob. 3PCh. 29.4 - Write a mechanism for the dehydration reaction of...Ch. 29.4 - Evidence for the role of acetate in fatty-acid...Ch. 29.4 - Does the reduction of acetoacetyl ACP in step 6...Ch. 29.5 - Prob. 7PCh. 29.5 - Look at the entire glycolysis pathway, and make a...Ch. 29.6 - Prob. 9PCh. 29.7 - Prob. 10P
Ch. 29.7 - Write mechanisms for step 2 of the citric acid...Ch. 29.7 - Prob. 12PCh. 29.8 - Prob. 13PCh. 29.9 - Write all the steps in the transamination reaction...Ch. 29.9 - What -keto acid is formed on transamination of...Ch. 29.9 - Prob. 16PCh. 29.SE - Prob. 17VCCh. 29.SE - Identify the following intermediate in the citric...Ch. 29.SE - The following compound is an intermediate in the...Ch. 29.SE - Prob. 20VCCh. 29.SE - In the pentose phosphate pathway for degrading...Ch. 29.SE - Prob. 22MPCh. 29.SE - One of the steps in the pentose phosphate pathway...Ch. 29.SE - One of the steps in the pentose phosphate pathway...Ch. 29.SE - Prob. 25MPCh. 29.SE - Prob. 26MPCh. 29.SE - Prob. 27MPCh. 29.SE - Prob. 28MPCh. 29.SE - Prob. 29MPCh. 29.SE - Prob. 30MPCh. 29.SE - Prob. 31MPCh. 29.SE - Prob. 32APCh. 29.SE - Prob. 33APCh. 29.SE - Prob. 34APCh. 29.SE - Prob. 35APCh. 29.SE - Prob. 36APCh. 29.SE - Prob. 37APCh. 29.SE - Prob. 38APCh. 29.SE - Prob. 39APCh. 29.SE - Prob. 40APCh. 29.SE - Prob. 41APCh. 29.SE - Prob. 42APCh. 29.SE - Prob. 43APCh. 29.SE - Prob. 44APCh. 29.SE - Prob. 45APCh. 29.SE - Prob. 46APCh. 29.SE - Prob. 47APCh. 29.SE - Prob. 48APCh. 29.SE - Prob. 49APCh. 29.SE - Prob. 50APCh. 29.SE - In glycerol metabolism, the oxidation of...Ch. 29.SE - Prob. 52APCh. 29.SE - Prob. 53APCh. 29.SE - Prob. 54APCh. 29.SE - In step 7 of fatty-acid biosynthesis (Figure...Ch. 29.SE - Prob. 56AP
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