HSN431, HSN459, and compound 24 among others, exhibited similar or better anti-leukemic activity against drug-resistant AML cells including MOLM-14 cells harboring double FLT3-ITD-D835Y and FLT3-ITD-F691 L mutations compared to midostaurin, crenolanib, quizartinib and ponatinib. This evidence concerns the gene FLT3 and acute myeloid leukemia.