Anti-proliferative activity of second-generation compounds. The IC50 values against MV4–11 (black), MOLM-14 (red), MOLM-14 (ITD, D835Y) (blue) and MOLM-14 (ITD, F691 L) (green) cells were plotted for each compound. Compounds with 15 nM or less IC50 against all 4 cell lines are marked with *. Each bar represents the average of triplicates plotted using GraphPad Prism software (GraphPad, La Jolla, CA). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)