Organic Chemistry&mod Mstg Etx Vp Ac Pkg
1st Edition
ISBN: 9780134466729
Author: Bruice
Publisher: Pearson Education
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Chapter 20, Problem 45P
Interpretation Introduction
Interpretation:
The structure of
Concept Introduction:
Lactulose is a class of disaccharide sugar that is synthetically prepared from galactose and fructose. It is used for the diagnosis of those patients who have gastrointestinal disorders.
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The disaccharide lactulose consists of a d-galactopyranose subunit and a d-fructofuranose subunit joined by a β-1,4-glycosidic linkage. After treatmentof lactulose with 1. excess CH3I/Ag2O, 2. HCl/H2O, the d-galactopyranose subunit was found to have one nonmethylated OH group, whereas thed-fructofuranose subunit had two. Draw the structure of α-lactulose.
An unknown carbohydrate of formula C12H22O11 reacts with Tollens reagent to form asilver mirror. An a@glycosidase has no effect on the carbohydrate, but a b@galactosidasehydrolyzes it to d-galactose and d-mannose. When the carbohydrate is methylated (usingmethyl iodide and silver oxide) and then hydrolyzed with dilute HCl, the products are2,3,4,6-tetra-O-methylgalactose and 2,3,4-tri-O-methylmannose. Propose a structure forthis unknown carbohydrate
An unknown reducing disaccharide is found to be unaffected by invertase enzymes. Treatment with an a@galactosidasecleaves the disaccharide to give one molecule of d-fructose and one molecule of d-galactose. When the disaccharideis treated with excess iodomethane and silver oxide and then hydrolyzed in dilute acid, the products are2,3,4,6-tetra-O-methylgalactose and 1,3,4-tri-O-methylfructose. Propose a structure for this disaccharide, and give itscomplete systematic name.
Chapter 20 Solutions
Organic Chemistry&mod Mstg Etx Vp Ac Pkg
Ch. 20.1 - Prob. 1PCh. 20.2 - Prob. 2PCh. 20.2 - Prob. 3PCh. 20.3 - Prob. 4PCh. 20.3 - Prob. 5PCh. 20.3 - Prob. 6PCh. 20.4 - Prob. 7PCh. 20.4 - Prob. 8PCh. 20.5 - Prob. 9PCh. 20.5 - Prob. 10P
Ch. 20.5 - Prob. 11PCh. 20.6 - Prob. 12PCh. 20.6 - Prob. 13PCh. 20.6 - Prob. 14PCh. 20.7 - Prob. 15PCh. 20.8 - Prob. 16PCh. 20.9 - Prob. 18PCh. 20.10 - Prob. 20PCh. 20.10 - Prob. 21PCh. 20.10 - Prob. 22PCh. 20.11 - Prob. 23PCh. 20.11 - Prob. 24PCh. 20.12 - Prob. 25PCh. 20.12 - Prob. 26PCh. 20.14 - Prob. 28PCh. 20.15 - Prob. 29PCh. 20.15 - Prob. 30PCh. 20.16 - Prob. 31PCh. 20.17 - Prob. 32PCh. 20.18 - Refer to Figure 20.5 to answer the following...Ch. 20 - Prob. 34PCh. 20 - Prob. 35PCh. 20 - Prob. 36PCh. 20 - Prob. 37PCh. 20 - Prob. 38PCh. 20 - Prob. 39PCh. 20 - Prob. 40PCh. 20 - Prob. 41PCh. 20 - Prob. 42PCh. 20 - Prob. 43PCh. 20 - Prob. 44PCh. 20 - Prob. 45PCh. 20 - Prob. 46PCh. 20 - Prob. 47PCh. 20 - Prob. 48PCh. 20 - The 1H NMR spectrum of D-glucose in D2O exhibits...Ch. 20 - Prob. 50PCh. 20 - Prob. 51PCh. 20 - Prob. 52PCh. 20 - Prob. 53PCh. 20 - Prob. 54PCh. 20 - Prob. 55PCh. 20 - Prob. 56PCh. 20 - Prob. 57PCh. 20 - Prob. 58PCh. 20 - Prob. 59PCh. 20 - Prob. 60PCh. 20 - Prob. 61PCh. 20 - A hexose is obtained when the residue of a shrub...Ch. 20 - Prob. 63PCh. 20 - Prob. 64PCh. 20 - Prob. 65PCh. 20 - Prob. 66PCh. 20 - Prob. 67PCh. 20 - Prob. 68PCh. 20 - Prob. 69PCh. 20 - Prob. 70PCh. 20 - Prob. 71PCh. 20 - Prob. 72PCh. 20 - Prob. 73P
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