An inhibitor of CSF1R (IC50 = 3.7 nM); selective for CSF1R over FLT3, PDGFRα, PDGFRβ, and KIT (IC50s = >3,300, 436, 2,300, and 476 nM, respectively; inhibits the proliferation of M-NFS-60 cells (IC50 = 18 nM); inhibits CSF1-induced CFS1R autophosphorylation in THP-1 cells (IC50 = 27 nM) and CSF1- and RANKL-induced osteoclast differentiation (IC50 = 9.3 nM)