PI3Kα-IN-15 is a potent PI3Kα inhibitor with an IC 50 of 0.15?μM. PI3Kα-IN-15 also has acceptable anti-proliferative activity (inhibits SKOV-3, T47D, NCI-H1975, NCI-H460, and MCF-7 growth with IC 50 values of 26.6?μM, 7.9?μM,? 32.1?μM,? 17.7??μM, and 9.4??μM, respectively. PI3Kα-IN-15 can be used for cancer research.