2026 Spring CHEM 0320 Name__________________________
Exam 2 Page 1
I. (28 points) Complete each of the following reaction schemes. Complete structures are required.
Include stereochemistry as appropriate. If stereoisomeric products form, draw one and write
“+enantiomer” or “+diastereomer” In the box.
1a. The following was part of the total synthesis of lemnardosinane A, which is a new sesquiterpenoid from
marine soft corals collected from the Xisha Islands in the South China Sea.
O O OH (PCC) O
LiAlH4 HCl/CrO3
O HO O
N
+diastereomer (+1) 5 4
O
TsOH N NaBH3CN HN
1b.
H 2N
4 +diastereomer (+1) 5
HO HO
OH OH
TsOH O O
1c. O
4
O
Br
PPh3
1d.
O OK O
+4 connectivity
+2 stereochem 6
, 2026 Spring CHEM 0320 Name__________________________
Exam 2 Page 2
II. (10 points)
2a. Procainamide was approved by the US FDA on June 2, 1950, under the brand name Pronestyl, which
was launched by Bristol-Myers Squibb in 1951.
2b. Draw the form of procainamide that predominates at pH = 7.
2c. Draw the structure of (E)-hex-4-en-2-one.
(E)-hex-4-en-2-one
+1 for ketone O
+1 for alkene
+1 for 6 carbons
+1 for trans 4
Exam 2 Page 1
I. (28 points) Complete each of the following reaction schemes. Complete structures are required.
Include stereochemistry as appropriate. If stereoisomeric products form, draw one and write
“+enantiomer” or “+diastereomer” In the box.
1a. The following was part of the total synthesis of lemnardosinane A, which is a new sesquiterpenoid from
marine soft corals collected from the Xisha Islands in the South China Sea.
O O OH (PCC) O
LiAlH4 HCl/CrO3
O HO O
N
+diastereomer (+1) 5 4
O
TsOH N NaBH3CN HN
1b.
H 2N
4 +diastereomer (+1) 5
HO HO
OH OH
TsOH O O
1c. O
4
O
Br
PPh3
1d.
O OK O
+4 connectivity
+2 stereochem 6
, 2026 Spring CHEM 0320 Name__________________________
Exam 2 Page 2
II. (10 points)
2a. Procainamide was approved by the US FDA on June 2, 1950, under the brand name Pronestyl, which
was launched by Bristol-Myers Squibb in 1951.
2b. Draw the form of procainamide that predominates at pH = 7.
2c. Draw the structure of (E)-hex-4-en-2-one.
(E)-hex-4-en-2-one
+1 for ketone O
+1 for alkene
+1 for 6 carbons
+1 for trans 4
