Fms-like receptor tyrosine kinase 3 (FLT3) has been emerging as an attractive target for the treatment of acute myeloid leukemia (AML). By modifying the structure of FN-1501, a potent FLT3 inhibitor, 24 novel 1H-pyrazole-3-carboxamide derivatives were designed and synthesized. Compound 8t showed strong activity against FLT3 (IC50: 0.089 nM) and CDK2/4 (IC50: 0.719/0.770 nM), which is more efficient than FN-1501(FLT3, IC50: 2.33 nM; CDK2/4, IC50: 1.02/0.39 nM). Compound 8t also showed excellent inhibitory activity against a variety of FLT3 mutants (IC50 < 5 nM), and potent anti-proliferative effect within the nanomolar range on acute myeloid leukemia (MV4-11, IC50: 1.22 nM). In addition, compound 8t significantly inhibited the proliferation of most human cell lines of NCI60 (GI50 < 1 μM for most cell lines). Taken together, these results demonstrated the potential of 8t as a novel compound for further development into a kinase inhibitor applied in cancer therapeutics.
Keywords: 1H-pyrazole-3-carboxamide; AML; Cyclin-dependent kinases; anti-cancer; fms-like receptor tyrosine kinase 3; protein kinase inhibitors.