Structure of Azathioprine
Azathioprine is a prodrug of 6-mercaptopurine and contains the following structural features:
Imidazole Ring: Attached to a purine analog.
Mercaptopurine Moiety: Linked via a thioester bond.
Chemical Formula: C₉H₁₃N₇O₃S
Mode of Action
Azathioprine acts as an immunosuppressant and antimetabolite by:
Prodrug Conversion: Metabolized into 6-mercaptopurine in the body.
Inhibition of Purine Synthesis: Blocks DNA and RNA synthesis in rapidly dividing cells.
Suppression of Immune Response: Inhibits proliferation of T and B lymphocytes, reducing immune activity.
Uses
Organ Transplantation: To prevent graft rejection.
Autoimmune Diseases: Such as rheumatoid arthritis, systemic lupus erythematosus (SLE), and inflammatory bowel disease (IBD).
Crohn's Disease and Ulcerative Colitis: As part of maintenance therapy.
Psoriasis: In severe cases unresponsive to other treatments.
