HI5, a potent inhibitor of tubulin and indoleamine 2,3-dioxygenase (IDO), exhibits an inhibitory concentration (IC50) of 70 nM in HeLa cells. It suppresses IDO expression, reduces kynurenine production, and enhances T cell activation and proliferation. Additionally, HI5 impedes tubulin polymerization and cell migration, induces G2/M phase arrest, and leads to apoptosis through the mitochondrial-dependent apoptosis pathway while generating reactive oxidative stress in HeLa cells, making it a valuable compound for anticancer research.