PFI-4 is primarily utilized in biochemical research as a selective inhibitor of the BRPF1 bromodomain, which plays a significant role in epigenetic regulation. By targeting this specific bromodomain, PFI-4 helps researchers study the mechanisms of gene expression and chromatin remodeling. Its application is particularly valuable in understanding diseases linked to epigenetic dysregulation, such as cancer, where bromodomain proteins are often implicated. This compound serves as a tool to explore potential therapeutic strategies by modulating bromodomain activity, aiding in the development of novel treatments for various disorders.