(a) The optical rotation [a] of aqueous samples of pure a-D-glucose D and pure ß-D-glucose were measured over time and a graph plotted (below). The optical rotation of both samples tends towards the same value, +52.7, as time proceeds. Explain, with the use of a diagram, why this trend is observed. +112 [x] +52.7 +19 Time

(a) The optical rotation [a] of aqueous samples of pure a-D-glucose D and pure ß-D-glucose were measured over time and a graph plotted (below). The optical rotation of both samples tends towards the same value, +52.7, as time proceeds. Explain, with the use of a diagram, why this trend is observed. +112 [x] +52.7 +19 Time

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter3: Stereoisomerism And Chirality

Section3.7: Optical Activity—how Chirality Is Detected In The Laboratory

Problem 3.9P

See similar textbooks

Similar questions

Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed antidepressants. SSRIs block the reabsorption of the neurotransmitter serotonin in the brain. Changing the balance of serotonin helps brain cells send and receive chemical messages, which in turn boosts mood. Two SSRI medications are Faverin (fluvoxamine, C15H21F3N2O2 ) and Zoloft (sertraline, C17H17Cl2N ). Determine the molar masses of Faverin and Zoloft
X 10 (select) v molecules of penicillin
CH2023 Q2 (b)
Determine the branch points and reducing ends of amylopectin. A 0.5g sample of amylopectin was analyzed to determine the fraction of the total glucose residues that are branch points in the structure. The sample was methylated and then digested, yielding 50 μmol of 2,3-methylglucose and 0.4 μmol of 1,2,3,6-tetramethyl glucose. (MWglucose = 162 g/mol, minus H2O) What fraction of the total residues are branch points? How many reducing ends does the amylopectin have?
2. Flavopiridol was the first semi-synthetic cyclin-dependent kinase inhibitor to be tested in clinical trials. Research has shown that co-administration of flavopiridol with drugs such as the taxanes had synergistic cytotoxic effects against a variety of tumour cells. HO но, HO O 1114 CI 2.1 Is flavopiridol a natural product? Explain your answer.
An unknown sugar is known to equilibrate between two forms, I and II, in aqueous solution. Thisequilibration can be followed by measuring the optical rotation of aqueous solutions of isolatedsamples of form I and II. When species I was dissolved in pure water and the optical rotation was measured, it gave aspecific rotation of [?] = +42.0°. Over time, this value decreased to a constant value of [?]= +0.2°. • When species II was dissolved in pure water and the optical rotation was measured, it gave aspecific rotation of [?] = -54.0°. Over time, this value decreased to constant value of [?]= +0.2°. • In each case, both forms I and II were shown to be present in the mixture at the end of theexperiment. Calculate the ratio of the two forms I and II present at equilibrium and comment on anyassumptions made in making that calculation.
The mutated form of hemoglobin (hemoglobin S, or HbS) in sickle-cell anemia results from the replacement of a glutamate residue by a valine residue at position 6 in the ß chain of the protein. Normal hemoglobin is designated HbA. Under conditions of low [O₂], HbS aggregates and distorts the red blood cell into a sickle shape. See image of eight aggregated HbS molecules. Sickled red blood cells are relatively inflexible and may clog capillary beds, causing pain and tissue damage. The sickled red blood cells also have a shorter life span, leading to anemia. Which amino acids would be expected to produce a similar sickling effect if substituted for Val at position 6? arginine phenylalanine Aggregate of HbS molecules lysine leucine alanine Sickling occurs in deoxyhemoglobin S but not in oxyhemoglobin S. Oxyhemoglobin has a small, hydrophobic pocket in a B chain ranion located in the interior of the neotain In daaxshamaalahin homauar thic nookat is laastad on the curfona of tha 0
CH2023 Q2(a)
Q3: Distinguish by the mention of one detector between the compounds with giving the cause and the detection result: 1-Glucose and Glyceride 2-Fructose and Sucrose
Most of the ultraviolet absorption of proteins at 280 nm is due to their content of a. Glutamate b. Tryptophan c. Alanine d. Aspartate
Using the generated linear equation: y = 0.7802457x - 0.0127078, calculate the concentration of free D-glucose (in mM) for each of the diluted hydrolyzed glycogen test solution. Diluted Hydrolyzed Glycogen Test Solution No. Absorbance (at 510 nm) 1 (blank) 0.0000 2 0.1211 3 0.2813 4 0.4615 5 0.6134 6 0.7901 7 0.9189
CO -110.5 -137.2 197.9 (g) CO2 -393.5 -394.4 213.6 (g) Hydrogen 130.58 g) Oxygen 02 205.0 (g) H20-285.83 -237.13 69.91 (1) The value of AS° for the catalytic hydrogenation of acetylene to ethene, C2H2 (g) + H2 (g) → C2H4 (g) is J/K• mol. Select one: O A. +18.6 O B. +112.0 O C. -112.0 O D. -18.6 E. +550.8