The human kinome has tremendous medical potential. In the past decade, mixed-lineage protein kinase 3 (MLK3) has emerged as an interesting and druggable target in oncogenic signaling. The important role of MLK3 has been demonstrated in several types of cancer. In a target hopping example we started with the focal adhesion kinase (FAK) inhibitor PF-431396 (), which shows off-target activity toward MLK3. We were able to develop highly active compounds in the single digit nanomolar range for MLK3. Furthermore, we achieved a dramatic shift in selectivity from FAK to MLK3. Here we present a new chemical class of MLK3 inhibitors, including our lead compound with an outstanding IC value of <1 nM in a biochemical MLK3 assay while simultaneously exhibiting kinome-wide selectivity.