RIPA-56 is an inhibitor of receptor interacting serine/threonine kinase 1 (RIPK1, IC50 = 13 nM). It is selective for RIPK1 over RIPK3 at 10 µM, as well as over a panel of additional kinases at 2 µM. RIPA-56 inhibits Z-VAD-FMK-induced necrosis in HT-29 cells (EC50 = 28 nM). In vivo, RIPA-56 (6 mg/kg) reduces...