An inhibitor of the MDM2 protein and XIAP mRNA interaction; binds to the RING domain of MDM2 (Kd - 2.34 μM); decreases the levels of MDM2 and XIAP; induces autoubiquitination and degradation of MDM2 and increases the half-life of p53 in EU-1 cells; cytotoxic to a variety of ALL and neuroblastoma cancer cell lines but not to NBMM cells; increases survival in an EU-1 mouse model of leukemia at 100 mg/kg