Pyrazolone based TGFbetaR1 kinase inhibitors.

Interruption of TGFβ signaling through inhibition of the TGFβR1 kinase domain may prove to have beneficial effect in both fibrotic and oncological diseases. Herein we describe the SAR of a novel series of TGFβR1 kinase inhibitors containing a pyrazolone core. Most TGFβR1 kinase inhibitors described to date contain a core five-membered ring bearing N as H-bond acceptor. Described herein is a novel strategy to replace the core structure with pyrazolone ring, in which the carbonyl group is designed as an H-bond acceptor to interact with catalytic Lys 232.