Concept explainers
Interpretation:
The structure of compound
Concept introduction:
Ruff degradation is a process in which an aldose is converted into another aldose containing one carbon less than the starting aldose. In this process, an aldose is converted into aldonic acid by oxidation with
Killani Fischer synthesis is the three step process: conversion of aldose into cyanohydrins; hydrolysis; and reduction. The overall use of Killani Fischer synthesis is to synthesize two diastereomeric aldoses with an increased asymmetric carbon from an aldose.
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Organic Chemistry
- Give me a clear handwritten answer with explanationarrow_forwardAldohexoses A and B both undergo Ruff degradation to give aldopentose C. On treatment with warm nitric acid, aldopentose C gives an optically active aldaric acid. B alsoreacts with warm nitric acid to give an optically active aldaric acid, but A reacts to givean optically inactive aldaric acid. Aldopentose C is degraded to aldotetrose D, whichgives optically active tartaric acid when it is treated with nitric acid. Aldotetrose D isdegraded to (+)@glyceraldehyde. Deduce the structures of sugars A, B, C, and D, and useFigure 23-3 to determine the correct names of these sugars.arrow_forwardCompound A is a D-aldopentose that can be oxidized to an optically inactive aldaric acid B. On Kiliani-Fischer chain extension, A is converted into C and D; C can be oxidized to an optically active aldaric acid E, but D is oxidized to an optically inactive aldaric acid F. What is the structure of compound F? • Use the wedge/hash bond tools to indicate stereochemistry where it exists. You do not have to explicitly draw H atoms. If a group is achiral, do not use wedged or hashed bonds on it. • Show stereochemistry in a meso compound. • Do not include lone pairs in your answer. They will not be considered in the grading.arrow_forward
- Which D-aldopentose is oxidized to an optically active aldaric acid and undergoes the Wohl degradation to yield a D-aldotetrose that is oxidized to an optically active aldaric acid?arrow_forwardTreatment with NaBH 4 converts aldose U into an optically inactive (meso) alditol V. Ruff degradation ofU gives W, whose alditol is optically inactive. Ruff degradation of W forms D-glyceraldehyde, thesimplest aldose. Upon Kiliani-Fischer synthesis, U is converted to two aldoses, X and Y. X is oxidized toan optically active aldaric acid Z. Y is oxidized to an optically inactive aldaric acid. Draw the structuresof D-glyceraldehyde, V, W, X, Y, and Z. Structure of compound U is shown below.arrow_forwardAn optically active D-aldopentose (A) produced an optically inactive alditol (B) upon treatment with H2/Pt. When the aldopentose (A) was subjected to a Ruff degradation, D-aldotetrose (C) was generated. The aldotetrose (C) gave an optically active aldaric acid (D) upon oxidation with HNO3. D-aldopentose (A) can be prepared from D-threose by a Killani Fischer synthesis. Propose structure of A through D.arrow_forward
- There are three (3) vials labeled A, B, and C known to contain the following monosaccharides. All three samples reduce Tollens and Fehling. By oxidation with dilute HNO3 an optically active aldaric acid is obtained for sample A and the remaining two give products without optical activity. When the three samples were subjected to an alkaline medium, it was observed that, after a certain time, samples A and C reached the same value of the specific rotation [α]. Select the RIGHT alternative: (a) Sample A is Galactose. (b) Sample B is Alosa. (c) Samples A and C are not related to each other by an epimerization process. (d) Sample C is Talose. (e) Samples B and C are epimers.arrow_forwardWhat aldoses are formed when the following aldoses are subjected to the Kiliani–Fischer synthesis: (a) d-threose; (b) dribose; (c) D-galactose?arrow_forwardTreatment with sodium borohydride converts aldose A to an optically inactive alditol. Wohl degradation of A forms B, whose alditol is optically inactive. Wohl degradation of B forms d-glyceraldehyde. Identify A and B.arrow_forward
- Which of the following are reducing sugars? Comment on the common name sucrosefor table sugar.(a) methyl a-d-galactopyranoside (b) b-l-idopyranose (an aldohexose)(c) a-d-allopyranose (d) ethyl b-d-ribofuranosidearrow_forwardb) Disaccharide E is a reducing sugar. It is hydrolyzed by an α-glycosidase enzyme, which means it contains an α- glycoside link. Treatment of E with Ag2O and excess MeDgives an octamethyl derivative F. Hydrolysis of F in dilute aqueous acid gives the pair of molecules shown below. Write the structures of E and F. (If the stereochemistry at a particular carbon is not determined by the above data, indicate this with a wavy line as shown below.) HO OMe OMe MeO MeO OH OMe Am OH OMe OMearrow_forwardIdentify A, B, C, and D in the preceding problem if D is oxidized to an optically inactive aldaric acid; if A, B, and C are oxidized to optically active aldaric acids; and if interchanging the aldehyde and alcohol groups of A leads to a different sugar.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningChemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage Learning