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Solutions for Carbohydrates and Nucleic Acids
(a) D-aldohexose (D configuration, aldehyde, 6 carbons)
(b) D-aldopentose (D configuration, aldehyde, 5 carbons)
(c) L-ketohexose (L configuration, ketone, 6 carbons)
(d) L-aldohexose (L configuration, aldehyde, 6 carbons)
(e) D-ketopentose (D configuration, ketone, 5 carbons)
(f) L-aldotetrose (L configuration, aldehyde, 4 carbons)
(g) 2-acetamido-D-aldohexose (D configuration, aldehyde, 6 carbons in chain, with acetamido group at C-2)
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CH2OH
H OH
CHO
HCN
HHO
CN
OHH
CH2OH CH2OH
H OH
CN
H OH
(b) The products are diastereomers with different physical properties. They could be separated by 
crystallization, distillation, or chromatography.
(c) Both products are optically active. Each has two chiral centers and no plane of symmetry.
+
(a)
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Ba(OH)2
Ba(OH)2 HNO3
HNO3
OH
COOH
H
HO H
COOH
OH
CH2OH
H
HO H
CN COOH
HHO
H
CH2OH
OHH2O
A CHCN
CHO
H
CH2OH
OH
COOH
OHH
H
COOH
OH
CN
OHH
H
CH2OH
OH OH
CH2OH
H
H OH
COOH
H2O
B D
COOH
HHO
H
COOH
OH
COOH
OHH
HO
COOH
H OH
COOH
H
H OH
COOH
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+
(−)-tartaric acid
meso-tartaric acid
(a)
(b)
(S,S)-(−)-tartaric acid (R,R)-(+)-tartaric acid (R,S)-meso-tartaric acid
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