Furthermore, a more pronounced effect on the growth of the MLL leukemia cells was observed for AS-99, with the GI50 values ranging from 1.8 μM to 3.6 μM (Fig. 5a), likely due to the improved cell permeability over AS-85 resulting from the methyl substitution of the basic nitrogen in the azetidine ring (Fig. 4a), which led to higher cLogP and decreased tPSA (Supplementary Table 2). Here, KMT2A is linked to leukemia.