Synthesis of imidazopyridines <i>via</i> NaIO ₄ /TBHP-promoted (3 + 2) cycloaddition and biological evaluation as anticancer agents

A novel and simple NaIO₄/TBHP-promoted (3 + 2) cycloaddition reaction of propargyl alcohols and 2-aminopyridines was discovered for the synthesis of imidazo[1,2-<i>a</i>]pyridines. This protocol exhibits a broad substrate scope for both propargyl alcohols and 2-aminopyridines, with high functional group tolerance, leading to the formation of various C3-carbonylated imidazopyridines in moderate yields. More importantly, these synthesized compounds were evaluated for their antiproliferation activity against MOLM-13 and MV4-11 cells, indicating that 3n, 5a and 5d possessed good bioactivity. Molecular docking analysis showed the strong interaction between 5a, 5d and FLT3 kinase, which have practical values in the development of kinase inhibitors.