PHA-767491 is primarily used in research settings as a potent ATP-competitive inhibitor of cell division cycle 7 (CDC7) and cyclin-dependent kinase 9 (CDK9). Its applications are significant in studying cell cycle regulation, particularly the initiation of DNA replication via CDC7 inhibition, and transcriptional regulation through CDK9 modulation. Researchers utilize this compound to investigate its effects on cancer cells, as inhibiting these kinases can disrupt cell proliferation, induce apoptosis, and interfere with tumor growth. Additionally, PHA-767491 is employed in studies of cellular responses to stress and DNA damage repair, making it a valuable tool for developing anti-cancer therapies and understanding oncogenic signaling pathways.