Used in cancer research, particularly in targeting DNA damage response pathways. It acts as a selective inhibitor of the ataxia telangiectasia and Rad3-related (ATR) kinase, which plays a key role in cell cycle regulation and DNA repair. By inhibiting ATR, the compound enhances the effectiveness of DNA-damaging agents such as chemotherapy and radiation, making it a candidate for combination therapy in solid tumors. It shows potential in tumors with high replication stress or defects in DNA repair mechanisms. Currently under investigation in clinical trials to evaluate safety, pharmacokinetics, and anti-tumor activity.