KAT2B and acute promyelocytic leukemia: Compounds 4a–n have been evaluated in p300, PCAF, SIRT1/2, EZH2 and CARM1 enzyme assays, and in NB4 human acute promyelocytic leukemia (APL), U937 AML, MCF-7 breast cancer and SH-SY5Y neuroblastoma cells, to determine their effects in cell cycle phases and apoptosis (sub-G1 peaks) induction.