PHA 767491 hydrochloride is a potent ATP-competitive inhibitor of CDC7 kinase (involved in DNA replication initiation) and CDK9 kinase (involved in RNA polymerase II-mediated transcription). It is primarily utilized in research settings to study cell cycle regulation, DNA synthesis mechanisms, replication stress, and transcriptional control. Researchers employ this compound to investigate cancer biology, as dual inhibition of CDC7 and CDK9 can potentially halt cancer cell proliferation and disrupt oncogenic gene expression. It is also used in studies exploring the development of targeted cancer therapies. Additionally, PHA 767491 hydrochloride serves as a valuable tool in biochemical and cellular assays to evaluate the efficacy of novel therapeutic agents targeting cell cycle- and transcription-related pathways.