Imidazoquinoxaline Src-Family Kinase p56^Lck Inhibitors:  SAR, QSAR, and the Discovery of (<i>S</i>)-<i>N</i>-(2-Chloro-6-methylphenyl)-2-(3-methyl-1-piperazinyl)imidazo- [1,5-<i>a</i>]pyrido[3,2-<i>e</i>]pyrazin-6-amine (BMS-279700) as a Potent and Orally Active Inhibitor with Excellent in Vivo Antiinflammatory Activity

Abstract

A series of novel anilino 5-azaimidazoquinoxaline analogues possessing potent in vitro activity against p56Lck and T cell proliferation have been discovered. Subsequent SAR studies led to the identification of compound 4 (BMS-279700) as an orally active lead candidate that blocks the production of proinflammatory cytokines (IL-2 and TNFalpha) in vivo. In addition, an expanded set of imidazoquinoxalines provided several descriptive QSAR models highlighting the influence of significant steric and electronic features. The H-bonding (Met319) contribution to observed binding affinities within a tightly congeneric series was found to be significant.