Design and synthesis of pyridazin-4-one derivatives as necroptosis inhibitors.

Necroptosis is a regulated inflammatory cell death process that is closely associated with autoimmune diseases, acute ischemic injuries, neurodegenerative disorders, and so on. Due to the crucial role of receptor-interacting protein kinase 1 (RIPK1) in the necroptosis pathway, RIPK1 inhibitors are believed to have great potential in the treatment of necroptosis-related diseases. In this article, we reported a series of pyridazin-4-one derivatives as potent necroptosis inhibitors for both human and mouse cells. The representative compound 13 exhibited favorable RIPK1 selectivity and dose-dependently inhibited RIPK1 phosphorylation. The in vivo pharmacokinetic study indicated that compound 13 was an orally available candidate. Finally, molecular docking and molecular dynamics simulations were performed to elucidate the binding pattern of compound 13 with RIPK1. Collectively, compound 13 represents a promising lead compound for the future development of RIPK1-targeted necroptosis inhibitors.