A new type of immunosuppressant is mainly used in prevention of renal graft rejection and transplant arteriosclerosis. It is also used in the treatment of kidney diseases.CAS No.: 53123-88-9 Molecular weight: 914.2 Chemical formula: C51H79NO13 Appearance: White or offwhite crystalline powder Water: 0.5% max. Content: 98.0% 102.0%.