A potent inhibitor of Cdc7 (IC50 = 3.4 nM); >60, >10, and >300-fold selective for Cdc7 over CK2, PIM1, and a panel of over 100 protein kinases, respectively; inhibits the growth of MDA-MB-231T and COLO 205 cells (IC50s = 118 and 140 nM, respectively); inhibits Cdc7-specific phosphorylation of MCM2 and induces cell cycle accumulation in the S and G2 phases in MDA-MB-231T and COLO 205 cells; inhibits MCM2 phosphorylation (ED50 = <3 mg/kg) and reduces tumor growth in a COLO 205 mouse xenograft model at 10, 30, and 100 mg/kg