A potent and allosteric inhibitor of PCR2 (IC50 = 23.4 nM in an enzyme assay with H3K27me0 peptide as the substrate); exhibits dose-dependent displacement of H3K27me3 binding to the EED subunit of PCR2; decreases global H3K27me3 and H3K27me2 in G401 cells and H3K27me3 in Karpas422 lymphoma cells in a dose-dependent manner; reduces proliferation of Karpas422 lymphoma cells in vitro and slows growth of Karpass422 xenografts in vivo