Student name:……………………………………… Registration no……………………………….. Section no.:……………….
Philadelphia University
Department of Pharmaceutical
Second semester 2012/2013
Sciences
Pharmaceutical Medicinal Chemistry-2
0510312
Second Examination-6/5/2013
Dr. Bilal Ali Al-Jaidi
Faculty of Pharmacy
Student name:
Registration no.:
This exam contains 7 questions:

You must answer all questions.

Exam will last for one hour.

Wish you a good luck.
Question-1: Choose the most appropriate answer for all the following questions (6 marks)
1. Which of the following statements is true regarding Chloramphenicol:
A. It has a broad spectrum antibacterial activity
B. The nitro group is important for activity
C. The nitro group has a role in the systemic toxicity of
chloramphenicol
D. Acetylation of hydroxyl groups does not affect its
antibacterial activity
E. A and C.
2. Which of the followings is true regarding quinolone antibacterial agents:
A. They are mainly active on gram –ve
bacteria
C. Can cause crystalluria
B. Fluoroquinolones are active against Ps.
aeruginosa
D. All of the above
3. Regarding aminoglycosides, the following is true:
A.
B.
C.
D.
E.
Not given orally because they are unstable
Have a large volume of distribution because they are non polar
Acetylated metabolite is more active than the parent drug
A and C
None of the above
Student name:……………………………………… Registration no……………………………….. Section no.:……………….
4. Regarding sparfloxacin, which of the following is true:
A. Piperazine ring has improved antipseudomonal activity.
B. Has high incidence of phototoxicity
C. Carboxylic acid is not important for activity
D. It is one of the fluoroquinolones antifungal
agents.
5. Regarding paromomycin, the following is true
A.
B.
C.
D.
Is a tetracycline antibiotic
Orally active
Does not contain glucosamine ring
None of the above
6. Regarding the SAR of quinolone antibacterials, the following is true:
A.
B.
C.
D.
E.
The keto group at C4 is important for activity
The nitrogen atom at C8 is important
Position 6 is better to be unsubstituted
Position 2 can be substituted with small alkyl
A and D
7. Chiral switching means:
A.
B.
C.
D.
Using the racemate instead of the toxic pure isomer
Converting one isomer to the other
One of the isomers is less active than the other
B and C
8. Regarding Gemifloxacin, the following is true:
A. Has a broad spectrum of activity
B. Addition of methoxy group on labelled carbon will
increase phototoxicity
C. Fluorine atom improves activity on gram -ve bacteria
D. The carboxylic acid is not important for its activity
E. Only A and B
Student name:……………………………………… Registration no……………………………….. Section no.:……………….
9. Parenteral tetracyclines should be freshly prepared because:
A. They have a short duration of action
B. They are heat sensitive
C. they rapidly epimerize to form inactive derivatives
D. None of the above
10. Regarding the structure of Gentamicin, the following is true:
A. More stable towards the inactivation by acetylation
B. It is stable if given orally
C. Better to be given topically
D. Only A and B
E. All of the above
Question-2: Draw the following drug structures: (3 marks)
Chloetetracycline
Sulfasalazine
Ciprofloxacin
Question-3: Chloramphenicol is widely used antibacterial agents, but it has a limited systemic uses
due to its toxicity, explain (by drawing suitable mechanism) how Chloramphenicol’s metabolism
plays a major role in this systemic toxicity? (2 marks)
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Student name:……………………………………… Registration no……………………………….. Section no.:……………….
Question-4: Production of deactivation enzyme is an example of bacterial resistant mechanism,
explain, and give two examples? (1 mark)
Question-5: Tetracycline’s structure has both acidic and basic characteristics, the selected group acts
as a moderate acidic group although it is an alcohol, explain why? (2 marks)
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Question-6: Co-trimoxazole is an example of sequential blocking drug combination, explain? (2
marks)
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Question-7: Explain with drawing suitable chemical structure why quinolone should not be given
with antacids and mineral supplements. (2 marks)
Question-8: regarding the following chloramphenicol derivatives, answer the following questions: (3
marks)
1. Which one is a prodrug for chloramphenicol, explain your answer?
2. Which one is better for intravenous administration, explain your answer?
3. The dichloroacetamido group plays a major role in their systemic toxicity, draw the mechanism for
this?