Page 15 - FPGEE Medicinal and Organic Chemistry Q&A Book

Krisman

239. The compound shown below inhibits 242. Which of the following statements is
which of the following enzymes? TRUE about improving the acid stability of
penicillin?
O
O

N R C NH CH
N H S 3
N CH 3
N N
H
O
a. MAO
COOH
b. COMT
Penicillin
c. Xanthine oxidase
d. Dihydro folate reductase a. The R substituent group should be
highly lipophilic.
240. What is the name of the heterocyclic
group found in the following structure? b. The R substituent group should be
highly hydrophilic.
N

c. The R substituent group should be a
NO 2 N CH 3 strong electron-withdrawing group.

CH CH OH
2 2
d. The R substituent group should be a
a. pyridine strong electron-donating group.
b. pyrazole
c. imidazole 243. To prepare beta-lactamase resistant
d. pyrrole penicillin, one should use:

241. The beta-lactam ring is also known as: a. The aromatic ring that is directly at-
tached to the side-chain carbonyl and both ortho
positions should be substituted by methoxy
N groups.
O H
Beta lactam ring b. The aromatic ring that is directly at-
tached to the side-chain carbonyl and ortho and
a. cyclic ketone para positions should be substituted by methoxy
b. cyclic amide groups.
c. cyclic ester
d. cyclic amine c. The aromatic ring that is directly at-
tached to the side-chain carbonyl and meta and
para positions should be substituted by methoxy
groups.

d. A methylene between the aromatic ring
and carbonyl group of side chain.

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