Properties: white or off white powder, odorless and tasteless. It is very soluble in methanol, ethanol or acetonitrile, soluble in ethyl acetate, soluble in acetone or ether, and almost insoluble in water. Purpose: biochemical research. Inhibition of T cell receptor signaling pathway.New immunosuppressants. It is a cyclic polypeptide composed of eleven amino acids. It inhibits the immune function transmitted by body fluid and cells, but does not inhibit bone marrow and reduce the number of leukocytes. It can prevent rejection of transplanted tissues or organs. It is used in kidney transplantation, liver, lung transplantation and heart transplantation, and it also has certain curative effects on autoimmune diseases, schistosomiasis, malaria, diabetes, AIDS, and anti-inflammatory performance.