5. Kunsa Janu (JAK) inhibitors and pharmaceutical ingredients containing such substances. 1. Claim 1: a formula compound (1),or a pharmaceutically acceptable salt thereof, wherein R¹ is hydrogen or C₁₋₄ alkyl,wherein the alkyl is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxy, methoxy, amino, CF₃ and C₃₋₆ cycloalkyl；R2 and R3 are independent of each other；C₁₋₆ straight or branched chain perfluoroalkyl, C₁₋₆ straight or branched chain alkoxy, C₁₋₆ straight or branched chain perfluoroalkoxy, halogen, cyano, hydroxyl, amino, carboxy, aminocarbonyl, aryl, heteroaryl, (aryl) alkyl C₁₋₆ straight or branched chain, (heteroaryl) straight or branched C₁₋₆ alkyl, (heterocyclic) straight or branched C₁₋₆ alkyl, (straight or branched C₁₋₆ alkyl) aryl, (alkyl C₁₋₆ straight or branched chain) heteroaryl, (straight or branched chain C alquilo alkyl) heterocyclic, (straight or branched chain C alco alkoxy) carbonyl,(C₁₋₆ straight or branched chain alkyl) aminocarbonylamino or (straight or branched C₁₋₆ alkyl) aminocarbonyl； R⁴ is selected from hydrogen, deuterium, straight or branched chain C₁₋₆ alkyl, C₁₋₆ straight or branched chain perfluoroalkyl, aryl and alkylaryl； X is selected from --NH-- and --CRᵃRᵇ--,wherein (a) Rᵃ and Rᵇ are independently hydrogen, deuterium, straight or branched chain C₁₋₆ alkyl, C₃₋₆ cycloalkyl,arilo (aril) alquilo C de cadena lineal o ramificada heteroarilo (alquilo C de cadena lineal o ramificada) heteroarilo (heteroaril) alquilo C de cadena lineal o ramificada (heteroc clico) alquilo C de cadena lineal o ramificada o (b) R y R wherein Rᶜ and Rᵈ are independently hydrogen, deuterium, straight or branched chain C₁₋₆ alkyl, aryl, (straight or branched chain C₁₋₆ alkyl) aryl, heteroaryl, (straight or branched chain C₁₋₆ alkyl) heteroaryl halo, CN, CF₃,Hydroxy, conh832220 or so8322； ch832323；This is - a-r83099,Where a is a link, - (ch8322). - 83242； - O - (cd83242). -and R⁵ is straight or branched c
