NMS-1286937 is a potent, selective and orally available PLK1 inhibitor, with IC50 of 2 nM. NMS-1286937 also shows inhibitory activities against FLT3, MELK, and CK2, with IC50s of 510, 744, and 826 nM, respectively. NMS-P937 possesses a pure ATP competitive mechanism with a reversible dissociation and no time dependency. NMS-P937 (10 μM) is selective with a marginal activity of 48% and 40% inhibition on PLK2 and PLK3, respectively. NMS-P937 shows antiproliferative activity against a panel of 137 cell lines, with IC50 values of below 100 nM for 60 of 137 cell lines and higher than 1 μM for only 9 of 137 cell lines. NMS-P937 shows cytotoxic activity against AmL-NS8 cells with IC50 of 36 nM.