Discovery of a Novel Class of Non-ATP Site DFG-out State P38 Inhibitors Utilizing Computationally Assisted Virtual Fragment-based Drug Design (vFBDD)

Discovery of a new class of DFG-out p38α kinase inhibitors with no hinge interaction is described. A computationally assisted, virtual fragment-based drug design (vFBDD) platform was utilized to identify novel non-aromatic fragments which make productive hydrogen bond interactions with Arg 70 on the αC-helix. Molecules incorporating these fragments were found to be potent inhibitors of p38 kinase. X-ray co-crystal structures confirmed the predicted binding modes. A lead compound was identified as a potent (p38α IC(50)=22 nM) and highly selective (≥ 150-fold against 150 kinase panel) DFG-out p38 kinase inhibitor.