Structure Activity Relationship
• Amide group as a substituent at phenyl group shows inhibitory action
against tyrosine kinases.
• Substitution at 6 position of diaminophenyl ring abolished the activity
• Introduction of methyl group in an ortho position to the amino group can
increase the selectivity of Bcr-Abl.
• Bioavailability and solubility can be enhanced by the introduction of N-
Mechanism of Action-
• Competitive and specific inhibition of Type II 5α-reductase.
• This leads to the inhibition of the conversion of androgens into 5α-dihydrotestosterone (DHT).
This results in decrease in the level of DHT in the serum and increase in the level of
testosterone concentration in serum.
• DHT is the principle androgen for the prostate growth, and thus, the decrease in the level of
DHT leads in the decrease in the volume of prostate.
• Finasteride also decreases the DHT level in the scalp and thus, help in hair regrowth and slow
Text book of Medicinal Chemistry, volume-1, K.Ilango, P.Vlentina.
Medicinal Chemistry, second edition, D.Sriram, P.Yogeeswari.
Wilson and Gisvold’s Textbook of Organic, Medicinal and Pharmaceutical