Design,synthesis And Biological Evaluation Of Novel 4-phenoxyquinoline Derivatives As C-Met Kinase Inhibitors

The HGF/c-Met signaling pathway plays an important regulatory role in physiological processes such as embryonic development,organ formation and angiogenesis,regulates cell growth and differentiation,and is widely distributed in mature tissues and organs,involved in wound healing and tissue regeneration.Based on the structure-activity relationship of 4-phenoxyquinoline c-Met kinase inhibitor,the clinical candidate drug Foretinib was used as a lead compound to retain its core structure.The principle of flattening,the principle of electronic isosteres and skeleton transitions are used,and computer-aided drug design is also combined.The original cyclopropyl-1,1-dimethylformamide moiety of Foretinib was replaced with a pyrazolo[1,5-a]pyrimidine-5-carboxamide structural fragment to give a novel core structure.A class(15)of 4-phenoxyquinoline c-Met kinase inhibitors(H series)containing pyrazolo[1,5-a]pyrimidine structure was designed and synthesized.The structure of all the target compounds was confirmed by MS and ~1H NMR.Using MTT assay,H460 and MKN-45 cells were used as test strains to detect the inhibitory activity of 15 target compounds on cancer cells.Among them,H-9 and H-15 have better inhibitory activity against H460 cells than the positive control drug Foretinib.The anti-tumor structure-activity relationship of these compounds was summarized.When the terminal benzene ring is substituted by an electron-withdrawing group(2-F,4-F),the antitumor activity of the compound can be remarkably improved.The drug sensitivity of H460 cells to H-15 and Foretinib was demonstrated by soft agar cloning experiments.AO-EB fluorescence staining showed that H-15 was concentration-dependent in the induction of apoptosis in H460 and MKN45 cells,and the apoptosis rate of H-15-administered group was higher than that of Foretinib-administered group.The results of Annexin-V-FITC and PI double labeling assay showed that the effect of H-15 on H460 cells was concentration-dependent;The results of PI staining showed that H-15 can block cell cycle in G2/M phase by flow cytometry.The results of molecular docking showed that the N atom of the quinoline ring,the NH and carbonyl O atoms of the amide bond,and the N atom on the pyrazolopyrimidine ring formed four hydrogen bonds with Met1160,Lys1110 and Asp1222,respectively.The quinoline ring forms aπ-πinteraction with Tyr1159.In addition to this,2-F of the terminal benzene ring forms a halogen hydrogen bond with Glu1127.This study laid the foundation for further study of 4-phenoxyquinoline Type II small molecule c-Met kinase inhibitors.