Discovery of novel morpholino-quinoxalines as PI3Kα inhibitors by pharmacophore-based screening

A pharmacophore model of PI3K alpha inhibitors was built using the DiscoveryStudio 2.0 package. Pharmacophore-based screening (PBS) retrieved a series of novel morpholino-quinoxalines as PI3K alpha inhibitors, as exemplified by 1a (PI3K alpha IC50: 0.44 mu M). All target compounds showed good in vitro cytotoxicity against tested human cell lines. A pharmacophore mapping analysis and docking study indicated that both the morpholino group and the sulfonyl group contributed significantly to the potent PI3K alpha inhibitory activity and cytotoxicity of the compounds.