Process chemists at Genentech recently published their work on development of a kilo-scale synthesis of JAK-1 inhibitor- GDC-4379 (Figure 1).1The central heterocyclic core of the molecule consists of a 4-aminopyrazole moiety (elaborated as the pyrazolopyrimidene amide- presumably the inhibitor hinge binding fragment in the kinase active site) with an additional aryl substituent at C-3 and