YLT-11 is a potent, selective, and orally active inhibitor of polo-like kinase 4 (PLK4), exhibiting dissociation constant (Kd) values of >10000 nM for PLK1, 653 nM for PLK2, >10000 nM for PLK3, and 5.2 nM for PLK4, respectively. It demonstrates antiproliferative effects, induces apoptosis, and causes cell cycle arrest at the G2/M phase, highlighting its anticancer activity.