The document discusses the structure-activity relationship of quinolines as urinary tract anti-infective agents. It outlines that the 1,4-dihydro-4-oxo-pyridin-3-carboxylic acid moiety is essential for antibacterial activity, and it must be annulated with an aromatic ring. Substitutions at certain positions, like fluorine at position 6, lower alkyl groups at position 1, and amino at position 5 result in compounds with antibacterial activity. Piperazine, N-methyl piperazine and pyrrolidine ring substitutions at position 7 also lead to active compounds.

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.