Synthesis and biological evaluation of 2,4-disubstituted phthalazinones as Aurora kinase inhibitors

A series of 2,4-disubstituted phthalazinones were synthesized and their biological activities, including antiproliferation, inhibition against Aurora kinases and cell cycle effects were evaluated. Among them, N-cyclohexyl-4-((4-(1-methyl-1H-pyrazol-4-yl)-1-oxophthalazin-2(1H)-yl) methyl) benzamide (12c) exhibited the most potent antiproliferation against five carcinoma cell lines (HeLa, A549, HepG2, LoVo and HCT116 cells) with IC50 values in range of 2.2-4.6 lM, while the IC50 value of reference compound VX-680 was 8.5-15.3 lM. Moreover, Aurora kinase assays exhibited that compound 12c was potent inhibitor of AurA and AurB kinase with the IC50 values were 118 +/- 8.1 and 80 +/- 4.2 nM, respectively. Molecular docking studies indicated that compound 12c forms better interaction with both AurA and AurB. Furthermore, compound 12c induced G2/M cell cycle arrest in HeLa cells by regulating protein levels of cyclinB1 and cdc2. These results suggested that 12c is a promising pan-Aurora kinase inhibitor for the potential treatment of cancer. (C) 2018 Elsevier Ltd. All rights reserved.