CHEM 332 – Spring 2016
Name:
Problem Set 4
Discussion Section: M
T
Due 4/15/2016
1. Predict the product of the following reactions.
O
OH
1)
O
HO
HO
OH
OH
Ph
H
cat. H +
2) Ac2O
cat. H +
OH
HNO 3
O
HO
HO
OH
OH
O
O
O
1) K 2CO 3, EtO
OEt
Br
NH
2) K 2CO 3, MeI
O
3) HCl, H 2O, Δ
2. Draw the structure of the peptide SMILE at physiological pH. Be sure to clearly denote
stereochemistry were appropriate.
F
3. Provide a reasonable arrow-pushing mechanism for the following reactions.
a)
OH
OH
HO
HO
HO
CH 3CH2OH, cat. H +
O
HO
HO
HO
O
OH
OEt
b)
S
OH
cat. HCl
H
HO
HO
HO
O
OH
SH
OH
S
OH
H
H
OH
H
OH
CH2OH
4.
Provide a reasonable arrow-pushing mechanism for the following reaction and explain
where each oxygen came from in the final product.
O
O
OH
H 3C
O
HO
HO
OH
OH
O
O
cat. H +
CH 3
O
CH 3
O
O
H 3C
O
H 3C
O
O
O
O
O
O
CH 3
CH 3
5. Propose a synthesis of isoleucine from butanal. You may use any inorganic reagents and any
organic reagent with less than 2 carbons.
O
O
H
H 2N
OH
6. Base pair mismatch in DNA is often detrimental and can have severe consequences. In the
case of a mismatch, it is possible to form a non-canonical base pair in order to maximize the
number of hydrogen-bonding interactions and minimize steric repulsion between the bases.
Using your understanding of organic chemistry, propose plausible structure for the bonding
interaction between an A-G mismatch.
N
H 2N
H
H
N
N
Adenine
N
H
N
N
N
N
Guanine
N
O
No hydrogen bonds & steric clash
therefore this interaction is bad!