α-Amino-4-(trifluoromethoxy)benzeneacetonitrile Hydrochloride is used in the preparation of 2-oxo-2,3-dihydropyrido[2,3-b]pyrazine-4(1H)-carboxamide derivatives as PDE2A inhibitors, as well as for substituted triazole and imidazole compounds as LMP7 inhibitors.