Structural and biological evaluation of halogen derivatives of 1,9-pyrazoloanthrones towards the design of a specific potent inhibitor of c-Jun-N-terminal kinase (JNK)

c-Jun N-terminal kinase (JNK), a member of the MAPK family, is associated with a variety of diseases and immune responses. To dissect the mechanistic role of JNKs in such processes, a specific inhibitor for JNKs holds great value. SP600125 is a widely used inhibitor of JNKs despite its non-specific activity. In an effort to obtain better specific inhibitors, three anthrapyrazolone halogenated derivatives have been synthesized and characterized. Among the three derivatives, 5-chloro-2-(2-chloroethyl)dibenzo[cd,g] indazol-6(2H)-one is clearly established as a specific inhibitor of JNK with augmented expression of chemokines in LPS-activated macrophages based on modelling studies followed by in vitro and ex vivo evaluation.