RESUMEN

We recently reported 1a (skepinone-L) as a type I p38α MAP kinase inhibitor with high potency and excellent selectivity in vitro and in vivo. However, as a type I inhibitor, it is entirely ATP-competitive and shows just a moderate residence time. Thus, the scope was to develop a new class of advanced compounds maintaining the structural binding features of skepinone-L scaffold like inducing a glycine flip at the hinge region and occupying both hydrophobic regions I and II. Extending this scaffold with suitable residues resulted in an interference with the kinase's R-Spine. By synthesizing 69 compounds, we could significantly prolong the target residence time with one example to 3663 s, along with an excellent selectivity score of 0.006 and an outstanding potency of 1.0 nM. This new binding mode was validated by cocrystallization, showing all binding interactions typifying type I1/2 binding. Moreover, microsomal studies showed convenient metabolic stability of the most potent, herein reported representatives.

Asunto(s)

Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Proteína Quinasa 14 Activada por Mitógenos/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Diseño de Fármacos , Humanos , Cinética , Modelos Moleculares , Unión Proteica , Relación Estructura-Actividad , Especificidad por Sustrato

RESUMEN

Skepinone-L was recently reported to be a p38α MAP kinase inhibitor with high potency and excellent selectivity in vitro and in vivo. However, this class of compounds still act as fully ATP-competitive Type I binders which, furthermore, suffer from short residence times at the enzyme. We herein describe a further development with the first Type I1/2 binders for p38α MAP kinase. Type I1/2 inhibitors interfere with the R-spine, inducing a glycine flip and occupying both hydrophobic regions I and II. This design approach leads to prolonged target residence time, binding to both the active and inactive states of the kinase, excellent selectivity, excellent potency on the enzyme level, and low nanomolar activity in a human whole blood assay. This promising binding mode is proven by X-ray crystallography.

Asunto(s)

Dibenzocicloheptenos/farmacología , Proteína Quinasa 14 Activada por Mitógenos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Sitios de Unión/efectos de los fármacos , Cristalografía por Rayos X , Dibenzocicloheptenos/síntesis química , Dibenzocicloheptenos/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Factores de Tiempo