Design, synthesis, and biological activity of 4-(imidazo[1,2-b]pyridazin-3-yl)-1H-pyrazol-1-yl-phenylbenzamide derivatives as BCR-ABL kinase inhibitors

A series of 4-((pyrazolo[1,5-a]pyrimidin-6-yl)-1H-pyrazol-1-yl)phenyl-3-benzamide derivatives and 4-((imidazo[1,2-b]pyridazin-3-yl)-1H-pyrazol-1-yl-)phenyl-3-benzamide derivatives were designed, synthesized as new Bcr-Abl tyrosine kinase inhibitors by using combinational strategies of scaffold hopping and conformational constraint. These new compounds were screened for BCR-ABL1 kinase inhibitory activity, and most of them appeared good inhibitory activity against BCR-ABL1 kinase. One of the most potent compounds 16a strongly suppressed BCR-ABL1 kinase with IC₅₀ value of 8.5nM. The tested compounds 16a and 16i showed strong inhibitory activities against K562 with IC₅₀ value of less than 2nM. Molecular docking studies indicated that these compounds fitted well with the active site of BCR-ABL1 protein. The results showed these inhibitors may serve as lead compounds for further developing new drugs targeted Bcr-Abl kinase.

BCR–ABL inhibitors; Bioactivity; Chronic myeloid leukemia; Molecular docking.