Communication
ChemComm
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of the hedgehog signaling pathway by chromones and their
derivatives has not been observed before.
In conclusion, we have developed a new highly efficient,
environmentally benign, oxidative direct coupling between non-
prefunctionalized chromones/isoflavones and the N1 center of
azoles. The desired products were formed by functionalization of
C–H bonds of chromones under transition metal free conditions
with exclusive regioselectivity. A novel dual role of 1,2,4-triazole
was explored to understand the interesting feasible mechanism.
Furthermore, the investigation of a chromone-azole based com-
pound collection in an assay that monitored signaling through
the hedgehog pathway revealed a novel class of inhibitors.
We gratefully acknowledge Prof. Dr Herbert Waldmann for
his generous support.
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