Design, synthesis and anticancer evaluation of 6,7-disubstituted-4-phenoxyquinoline derivatives bearing 1,8-naphthyridine-3-carboxamide moiety as novel multi-target TKIs

[Display omitted] •32 novel 6,7-disubstituted-4-phenoxyquinoline derivatives bearing 1,8-naphthyridine-3-carboxamide moiety were designed and synthesized.•The most active compound 33 exhibited a potent antiproliferative activity against three cancer cell lines.•Compound 33 dose dependently induced apoptosis and arrested at G1 phase of A549 cells.•33 is a multi-target TKI with the high efficiency against c-Met, MEK1, and Flt-3.•Compound 33 showed strong in vivo antitumor activity in the A549 xenograft mouse model. Giving the fact that the disorders of multiple receptor tyrosine kinases (RTKs) are characteristics of various cancers, we assumed that developing novel multi-target drugs might have an advantage in treating the complex cancers. Taking the multi-target c-Met inhibitor Foretinib as the leading compound, we discovered a novel series of 6,7-disubstituted-4-phenoxyquinoline derivatives bearing 1,8-naphthyridine-3-carboxamide moiety with the help of molecular docking. Among them, the most promising compound 33 showed a prominent activity against Hela (IC50 = 0.21 µM), A549 (IC50 = 0.39 µM), and MCF-7 (IC50 = 0.33 µM), which were 3.28–4.82 times more active than that of Foretinib. Additionally, compound 33 dose dependently induced apoptosis by arresting A549 cells at G1 phase. Enzymatic assays and docking analyses were further confirmed that compound 33 was a multi-target inhibitor with the strong potencies against c-Met (IC50 = 11.77 nM), MEK1 (IC50 = 10.71 nM), and Flt-3 (IC50 = 22.36 nM). In the A549 cells mediated xenograft mouse model, compound 33 inhibited the tumor growth (TGI = 64%) without obvious toxicity, establishing compound 33 as a promising candidate for cancer therapy.