Cell-permeable. A selective, ATP-competitive inhibitor of Aurora B kinase in vitro (IC50 values are 50 nM, 250 nM and 1 μM for Aurora B, C and A kinases respectively). Selective over a range of other kinases including cdk1 and PLK1 (IC50 > 10 μM). MW: 513.59. Purity ≥98% by HPLC