Medicinal Chemistry e-content for Pharmacy students

1. SAR of Quinolines/Urinary tract
Anti-infective Agents
Presenting by:
Mr. Purushotham K N
Asst. Professor
Dept. of Pharm. Chemistry
SACCP, B.G Nagar
Karnataka

2. Quinolones
Structure Activity Relationship(SAR);The quinoline antibacterial comprises a
group of synthetic substances possessing a common N-1-alkylated-3-carboxy-4-
one ring fused to another aromatic ring.
Urinary tract Anti-infective Agents

3. The general structural requirements for antibacterial activity can be summarized as follows.
• 1,4-Dihydro-4-oxo-pyridin-3-carboxylic acid moiety is essential for antibacterial activity.
• The pyridone system must be annulated with an aromatic ring.

4. • Replacement of nitrogen for carbon at position 2, 5, 6 and 8 are consistent with retention of
antibacterial activity.
 Introduction of substituents at position 2 greatly reduces the activity.

5. • Presence of 4-oxo group is must for activity.

6. • Fluorine atom substitution at position 6 is associated with significantly enhanced
antibacterial activity.
• Alkyl substitution at position 1 is essential for activity. Lower alkyl group
(methyl, ethyl, cyclopropyl) compounds are having greater potency.

7. • Aryl substitution at position 1 is also having consistent activity.
• Amino substitution at position 5 gives active compound.

8. • Piperazine, N-methyl piperazine and pyrrolidine ring substitution at
position 7 gives active compounds.
• Chlorine substitution at position 6 results in an active compound.