From Hit to Lead: Structure-Based Optimization of Novel Selective Inhibitors of Receptor-Interacting Protein Kinase 1 (RIPK1) for the Treatment of Inflammatory Diseases.

Receptor-interacting protein kinase 1 (RIPK1) is a key regulator of cellular necroptosis, which is considered as an important therapeutic target for necroptosis-related indications. Herein, we report the structural optimization and structure-activity relationship investigations of a series of eutectic 5-substituted-indole-3-carboxamide derivatives. The prioritized compound exhibited low nanomolar IC values against RIPK1 and showed good kinase selectivity. Based on its eutectic structure, occupied both the allosteric and ATP binding pockets of RIPK1, making it a potent dual-mode inhibitor of RIPK1. , had a potent protective effect against necroptosis in cells. Compound also provided robust protection in a TNFα-induced systemic inflammatory response syndrome (SIRS) model and imiquimod (IMQ)-induced psoriasis model. It also showed good pharmacokinetic properties and low toxicity. Overall, is a promising lead compound for drug discovery targeting RIPK1 and warrants further study.