A 1-ribosylimidazolecarboxamide in which the carboxamide group is situated at position 4 of the imidazole ring, which is further substituted at position 5 by an amino group. A purine nucleoside analogue and activator of AMP-activated protein kinase, it is is used for the treatment of acute lymphoblastic leukemia and is reported to have cardioprotective effects.