Azathioprine-d3 (BW 57-322-d3) is the deuterium labeled Azathioprine . Azathioprine (BW 57-322) is an orally active immunosuppressive agent. Azathioprine can be converted in vivo to the active metabolite 6-mercaptopurine (6-MP). Azathioprine has myelosuppressive effects and induces apoptosis.