High affinity and selective Aurora kinase inhibitor (Ki values are 0.6, 5 and 18 nM for Aurora A, Aurora C and Aurora B, respectively). Also exhibits affinity for FLT-3 and Abl. Exhibits selectivity for Aurora kinase over 190 other protein kinases. Inhibits proliferation and induces apoptosis in a number of cancer cell lines in vitro. Reduces tumor size in leukemia and colon cancer cell xenografts in mice. Purity 98%. MW (observed): 464.59