SW155246 is an inhibitor of DNA methyltransferase 1 (DNMT1; IC50 = 1.2 μM). It is selective for human DNMT1 over murine DNMT3 (IC50 = 38 μM). SW155246 inhibits HeLa and A549 tumor cell growth in a redox-independent manner (IC50s = 8-20 μM). It also inhibits genomic methylation in HeLa cells when used at concentrations ranging from 10 to 18.6 μM.