Compound 1 exhibited potent activity against proliferation of MLL1-r leukemia cells Molm-13 and MV4;11 with EC50 values of 320 and 570 nM (Fig. 6a and Additional file 1: Figure S4), while the parent inhibitor SGC-iMLLT and thalidomide were inactive (EC50 > 50 μM) except that SGC-iMLLT had weak activity against Molm-13 cells. This evidence concerns the gene KMT2A and leukemia.