Chemical. CAS 59865-13-3. Formula C62H111N11O12. MW 1202.6. Isolated from Tolypocladium inflatum. Potent immunosuppressant same as FK-506 Prod. No. AG-CN2-0047 and rapamycin Prod. No. AG-CN2-0025. Forms a complex with cyclophilin. Inhibits the activity of the calcium/calmodulin-dependent protein phosphatase 2B PP2B calcineurin. Prevents the dephosphorylation of nuclear factor of activated T cells NFAT transcription factor, leading to disruption of T cell activation. Suppresses proliferation of cytotoxic T cells and inhibits the production of T cell-derived mediators such as interleukin-2 IL-2. Prevents rejection of transplanted organs. Anti-inflammatory compound in the treatment of several inflammatory skin diseases e.g. atopic dermatitis and with potential anti-rheumatic activity rheumatoid arthritis. Antibacterial. Antifungal. Antiparasitic. Apoptosis inhibitor.