Design and synthesis of benzoazepin-2-one analogs as allosteric binders targeting the PIF pocket of PDK1

A novel series of benzoazepin-2-ones were designed and synthesized targeting the PIF pocket of AGC protein kinases, among which a series of thioether-linked benzoazepin-2-ones were discovered to bind to the PIF pocket of 3-phosphoinositide-dependent kinase-1 (PDK1), and to displace the PIF peptide with an EC50 values in the lower micromolar range. The structure–activity relationships (SARs) of the linker region, tail region, and distal region were explored to further optimize these novel binders which target the PIF pocket of PDK1. When tested in an in vitro PDK1 enzymatic assay using a peptide substrate, the benzodiazepin-2-ones increased the activity of the enzyme in a concentration-dependent fashion, indicating these compounds act as PDK1 allosteric activators. These new compounds may be further developed as therapeutic agents for the treatment of diseases where the PDK1-mediated AGC protein kinases are dysregulated.

Graphical abstractDesign, synthesis and SARs of novel series of 2-thio-benzoazepin-2-one analogs as allosteric activators of PDK1 targeting the PIF pocket are reported.Figure optionsDownload full-size imageDownload as PowerPoint slide