Discovery of 5-Amino-N-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamide Inhibitors of IRAK4.
Lim, J., Altman, M.D., Baker, J., Brubaker, J.D., Chen, H., Chen, Y., Fischmann, T., Gibeau, C., Kleinschek, M.A., Leccese, E., Lesburg, C., Maclean, J.K., Moy, L.Y., Mulrooney, E.F., Presland, J., Rakhilina, L., Smith, G.F., Steinhuebel, D., Yang, R.(2015) ACS Med Chem Lett 6: 683-688
- PubMed: 26101574 
- DOI: https://doi.org/10.1021/acsmedchemlett.5b00107
- Primary Citation of Related Structures:  
4Y73 - PubMed Abstract: 
Interleukin-1 receptor associated kinase 4 (IRAK4) is an essential signal transducer downstream of the IL-1R and TLR superfamily, and selective inhibition of the kinase activity of the protein represents an attractive target for the treatment of inflammatory diseases. A series of 5-amino-N-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamides was developed via sequential modifications to the 5-position of the pyrazolopyrimidine ring and the 3-position of the pyrazole ring. Replacement of substituents responsible for poor permeability and improvement of physical properties guided by cLogD led to the identification of IRAK4 inhibitors with excellent potency, kinase selectivity, and pharmacokinetic properties suitable for oral dosing.
Organizational Affiliation: 
Departments of Chemistry, Immunology, Chemistry Modeling and Informatics, Drug Metabolism and Pharmacokinetics, In Vitro Pharmacology, In Vivo Pharmacology, and Structural Chemistry, Merck & Co., Inc. , 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.