5-amino-pyrazoles as potent and selective p38α inhibitors.

The synthesis and structure–activity relationships (SAR) of p38α MAP kinase inhibitors based on a 5-amino-pyrazole scaffold are described. These studies led to the identification of compound 2j as a potent and selective inhibitor of p38α MAP kinase with excellent cellular potency toward the inhibition of TNFα production. Compound 2j was highly efficacious in vivo in inhibiting TNFα production in an acute murine model of TNF production. X-ray co-crystallography of a 5-amino-pyrazole analog 2f bound to unphosphorylated p38α is also disclosed.