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1. Structure Activity Relationship of
Antipsychotic Drug -:
SAR of Phenothaizines
SAR of Fluro butyrophenone

2. SAR of Phenothiazines

3. Neuroleptic activity of phenothiazines is
affected by three types of substitution -:
1.Nature of chain at position 10
2. Nature of amino group present in
side chain
3. Substitution at second position

4. Nature of chain at position 10
1.When nitrogen of phenothiazines ring and
more basic side chain nitrogen is connected by
three carbon chain maximum activity
obsereved.
2.Branching at beta position of side chain
with small methyl group dicreases activity.

5. Example
3. Bridging of position third of side chain to
position one of phenothiazines ring dicreases
activity.
1'
2'
3'
1

6. Nature of amino group present in side
chain -:
1.Maximum activity and potency is
observed with tertiary amino group .
2. Alkylation of basic amino group
with group larger than methyl group
dicreases activity.

7. Example
Prochlorperperazine
3. The ring analogues at basic amino group are
more potent than dimethyl Analogues.

8. Substitution at second position
1. Potency increases in following order of
ring substitution .
1< 4< 3< 2
2. Second position substitution increases
neuroleptic activity in following order.
OH< H< CH3 <CF3

9. 3.Disubstitution at ring is detrimental for activity .
4.Oxiadation of sulphure at position 5 dicreases the
activity of compound.

10. SAR of Fluro butyrophenone
Y
X

11. 1. All compound have 4 fluro Phenyl group
which is essential for activity .
2. Reduction or replacement of carbonyl group
results in decrease activity of compound .
3. Lengthening , shortening and branching of
propylene chain results in dicreased neuroleptic
activity.
4. Basic nitrogen of butyrophenone ring should
be a part of six membered ring .