Discovery, Optimization, and Evaluation of Potent and Highly Selective PI3Kγ–PI3Kδ Dual Inhibitors

An electronic density model was developed and used to identify a novel pyrrolotriazinone replacement for a quinazolinone, a commonly used moiety to impart selectivity in inhibitors for PI3Kγ and PI3Kδ. Guided by molecular docking, this new specificity piece was then linked to the hinge-binding region of the inhibitor using a novel cyclic moiety. Further structure–activity relationship optimization around the hinge region led to the discovery of candidate 26, a highly potent and selective PI3Kγ–PI3Kδ dual inhibitor with favorable drug metabolism and pharmacokinetic properties in preclinical species.