[EN] PROCESS FOR PREPARING MEDICAMENTS [FR] PROCÉDÉ DE PRÉPARATION DE MÉDICAMENTS
摘要:
The present application affords an improved preparation of 3-(5-chloro-2-(difluoromethoxy)phenyl)-1H-pyrazol-4-amine hydrochloride qhich was a useful intermediate in the synthesis of JAK inhibitors.
The development of an improved kilogram-scale synthesis of the JAK1 inhibitor GDC-4379 for the treatment of asthma is described. The new process is highlighted by a step-economical construction of a 3-substituted-4-aminopyrazole employing a telescoped oximation and hydrazine condensation of a 1,3-dielectrophile to generate nitrosopyrazole and a novel copper-catalyzed NaBH4 reduction of the nitroso