(-)-Zuonin A (D-Epigalbacin), a naturally occurring lignin, is a potent, selective JNKs inhibitor, with IC 50 s of 1.7 μM, 2.9 μM and 1.74 μM for JNK1 , JNK2 and JNK3 , respectively In Vitro (−)-zuonin A binds the D-recruitment site (DRS) of JNK, a recruitment site utilized by substrates and other substrates to dock onto and recognize MAPKs. (−)-zuonin A inhibits the activation and phosphorylation of JNK by MKK4 and MKK7. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Form:Solid IC50& Target:JNK1 1.7 μM (IC 50 ) JNK2 2.9 μM (IC 50 ) JNK3 1.74 μM (IC 50 )