RIPK1-IN-26 (Compound 8a) is a potent receptor-interacting serine/threonine-protein kinase 1 ( RIPK1 ) inhibitor with cell anti-necroptosis potency. RIPK1-IN-26 demonstrats good metabolic stability and good binding specificity in mice. RIPK1-IN-26 is promising for research of PET imaging probe development and neurodegenerative disorders.