Trk-IN-10 (Compound 14j) is a potent inhibitor of TRK ( IC 50 = 0.86, 6.92 nM, against TrkA , TrkA G595R , respectively). As a receptor tyrosine kinase (RTK), tropomyosin receptor kinase ( Trk ) is a key agent target in solid tumors. Trk-IN-10 ( IC 50 = 350 nM against ALK) has a higher selectivity of Trk inhibition, which may be of great significance for reducing toxicity.