BMH-21 is primarily used in biomedical research as a potent inhibitor of RNA polymerase I (Pol I), which plays a key role in ribosomal RNA synthesis. By selectively targeting Pol I, BMH-21 disrupts ribosome biogenesis, a process often hyperactive in cancer cells, making it a valuable tool for studying cancer cell proliferation and survival. It has shown selective cytotoxicity against various cancer cell lines, especially those with high ribosomal demand, and is used to investigate mechanisms of nucleolar stress and p53 activation. Additionally, BMH-21 helps researchers explore the role of transcription inhibition in tumor suppression and is being studied for its potential as a lead compound in developing novel anticancer therapies. Its ability to induce DNA damage responses without directly damaging DNA makes it a unique probe in molecular oncology studies.