Identification of 2-acylaminothiophene-3-carboxamides as potent inhibitors of FLT3

A series of 2-acylaminothiophene-3-carboxamides has been identified which exhibit potent inhibitory activity against the FLT3 tyrosine kinase. Compound 44 inhibits the isolated enzyme (IC50 = 0.027 μM) and blocks the proliferation of MV4-11 cells (IC50 = 0.41 μM). Structure–activity relationship studies within this series are described in the context of a proposed binding model within the ATP binding site of the enzyme.