Design, synthesis and bioactivity evaluation of selenium-containing PI3Kδ inhibitors

•A series of Se-containing compounds were designed, synthesized as potent PI3Kδ inhibitors.•Compound Se15 showed potent PI3Kδ inhibitory activity with an IC50 value of <0.1 nM and effectively anti-proliferative activity against SU-DHL-6 cells with an IC50 value of 0.16 μM.•Molecular docking study showed Se15 formed multiple hydrogen bonds with PI3Kδ and was close stacking with the selective region.•This study suggested that introduction of selenium can provide a new idea for design of novel PI3Kδ inhibitors.