Discovery of a Series of 5,11-Dihydro-6H-benzo[e]pyrimido[5,4-b][1,4]diazepin-6-ones as Selective PI3K-δ/γ Inhibitors

Dual inhibition of PI3K-delta and PI3K-gamma is an established therapeutic strategy for treatment of hematological malignancies. Reported molecules targeting PI3K-delta/gamma selectively are chemically similar and based upon isoquinolin-1(2H)-one or quinazolin-4(3H)-one scaffolds. Here we report a chemically distinct series of potent, selective PI3K-delta/gamma inhibitors based on a 5,11-dihydro-6H-benzo[e]pyrimido[5,4-b][1,4]diazepin-6-one scaffold with comparable biochemical potency and cellular effects on PI3K signaling. We envisage these molecules will provide useful leads for development of next-generation PI3K-delta/gamma targeting therapeutics.