We further found that representative compounds 2j, 2t, 2v, 2w and 3g, which displayed potent tumor-selective cytotoxic, have intracellular KDM inhibition activities in an orthogonal assay which measures heterochromatin gene repression velocity following HP1 recruitment to the CiA:Oct4 locus. This evidence concerns the gene POU5F1 and neoplasm.