Discovery of TRD‐93 as a novel DRAK2 inhibitor.

Death‐associated protein kinase‐related apoptosis‐inducing protein kinase 2 (DRAK2) has become a promising target for drug development. In search of novel and selective DRAK2 inhibitor motif, in vitro screen kinase assay was established performed using in‐house chemical libraries. After through hit triage procedure, N2‐(3,5‐dichlorophenyl)‐5‐fluoro‐N4‐methylpyrimidine‐2,4‐diamine (1) was selected as initial hit with structural novelty and drug‐likeness. During hit validation, structure–activity relationship of 1 was thoroughly disclosed and TRD‐93 was finally validated as hit for DRAK2 inhibition. TRD‐93 is small (mw = 290) but selectively potent to DRAK2 (IC50 = 0.16 μM) over other kinases including DAPK family kinases. Molecular binding model study of TRD‐93 to DRAK2 is also discussed. [ABSTRACT FROM AUTHOR]