Used as a selective inhibitor of the mitotic kinesin Eg5 (kinesin-5), this compound plays a key role in cell cycle research, particularly in studies related to spindle assembly and mitotic arrest. It induces the formation of monopolar spindles in dividing cells, making it a valuable tool for investigating mitotic mechanisms and cancer cell proliferation. Due to its ability to block Eg5 ATPase activity, it is employed in the development and validation of anti-mitotic drug candidates for cancer therapy. Commonly used in in vitro assays and cell-based studies, it helps elucidate the function of motor proteins in cellular division and supports high-throughput screening for novel chemotherapeutic agents.