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682 Chapter 20
Copyright © 2017 Pearson Education, Inc.
14.
a.
l-gulose (Note the similarity of this problem to Problem 13. a. 2.)
OH H
H HO
OH H
OH H
CH
2
OH
OH H
H HO
OH H
OH H
C
O OH
CH
2
OH
OH H
H HO
OH H
OH H
rotate 180
°
H HO
H HO
OH H
H HO
CH
2
OH
D
-glucose
D
-glucaric acid
L
-gulose
HNO
3
HNO
3
C
H O
C
HO O
C
H O
C
O H
b.
l-Gularic acid because it is also the oxidation product of l-gulose.
c.
d-allose and l-allose, d-altrose and d-talose, l-altrose and l-talose, d-galactose and l-galactose
15.
The monosaccharides are the aldoses with one additional carbon that are C-2 epimers and whose other
asymmetric centers have the same configuration as the given aldose.
a.
d-gulose and d-idose
b.
l-xylose and l-lyxose
16.
The monosaccharides are the aldoses whose C-1 carbon has been removed, whose C-2 carbon has been con-
verted to an aldehyde, and whose other asymmetric centers have the same configuration as the given aldose.
a.
d-allose and d-altrose
b.
d-glucose and d-mannose
c.
l-allose and l-altrose
17.
Solved in the text.
18.
OH
HO H
H OH
H OH
CH
2
OH
D
-glucose
H
H
HO H
H OH
H OH
CH
2
OH
D
-mannose
HO
HO H
H OH
H OH
CH
2
OH
D
-arabinose
H OH
H OH
CH
2
OH
D
-erythrose
D
C
A
B
C
H O
C
H O
C
H O
C
H O