Cyclin-dependent kinases (CDKs) play a key role in regulating cell division by phosphorylating distinct substrates in different phases of the cell cycle. Cell cycle deregulation in many cancers often results from altered CDK activity. Thus, CDKs are potential pharmacological targets for anticancer agents. NU 6027 inhibits both CDK1 and CDK2 with IC50 values of 2.9 and 2.2 μM, respectively. It has been shown to inhibit cellular ataxia telangiectasia mutated and Rad3-realted kinase activity (IC50 = 6.7 μM) and impair G2/M arrest in various human cancer cells, potentiating the cytotoxic effects of DNA-damaging, anticancer agents such as cisplatin.