Problem Set Chapter 24
Organic Chemistry for
Life Sciences: CHM 224
Section A
Name__________________________
DUE: March 21
1. Draw Fischer projections for all of the non-naturally occuring ketopentoses
2. Draw the Fischer projection for the enantiomer of D-Lyxose (provided below):
CHO
HO
H
HO
H
H
OH
CH2OH
3. Which of the following terms correctly describe the relationship between D-Idose and D-Gulose (may be
more than one):
HO
H
HO
H
CHO
H
OH
H
OH
CH2OH
H
H
HO
H
CHO
OH
OH
H
OH
CH2OH
A.
B.
C.
D.
E.
enantiomers
epimers
anomers
diastereomers
stereoisomers
D-Gulose
D-Idose
4. Draw the two pyranose rings that would be formed from D-idose and name them:
5. Draw the Fischer projection of the monosaccharide from which the following pyranose ring was formed:
CH2OH
O
OH
OH
OH
OH
6. Prior to establishing a final equilbrium via mutarotation, a solution of glucopyranose has [α] = +40.4.
Which anomer predominates in solution at that point in time? Briefly explain.
7. Insulin is the small protein the human body uses as a hormone (a chemical messenger) to allow glucose to
be absorbed by cells and to eventually lower blood glucose levels. Insulin is released once the pancrease is
signalled that glucose levels are on the rise (i.e., shortly after eating). If a person does not eat, the cells still
need a source of glucose to remain functional. The pancreas releases a second homorne called glucagon.
What is the function of glucagon and how do these two hormones work in unison to stabilize blood sugar
levels (you'll have to research this answer a bit)?
8. Without looking at the structures in the textbook or notes, what will be the two aldopentoses formed
from a round of Kiliani-Fischer synthesis upon the following sugar:
CHO
HO
H
HO
H
CH2OH
9. The following sugar is drawn in "non-standard" format. Answer the questions based on its structure:
A. circle the acetal carbon
CH2OH
OCH3
O
OH
HO
OH
B. is this a reducing sugar?
C. is this an α or β anomer?
D. does this sugar undergo mutarotation in neutral solution?
10. The structure of Gentiobiose is provided below. Answer the questions based on its structure"
A. Is Gentiobiose a simple or complex sugar?
B. Is Gentiobise a reducing sugar?
I
C. Is ring I an α or β anomer?
D. Does Gentiobiose undergo mutarotation in neutral solution?
E. How many types of saccharides are released upon cleavage of the
glycosidic linkage?