Design and synthesis of novel substituted naphthyridines as potential c-Met kinase inhibitors based on MK-2461.

Two series of novel 1,5-naphthyridine and 1,6-naphthyridine derivatives were designed and synthesized based on the c-Met kinase inhibitor MK-2461 under the guidance of scaffold hopping strategy. All were tested on c-Met kinase and in vitro anti-tumor activities against Hela and A549 cell lines. The results indicated that 1,6-naphthyridine was a more promising c-Met inhibitory structure core compared with 1,5-naphthyridine. Among them, 26b and 26c showed the best enzymic and cytotoxic activities. The western blot experiments implied that the cytotoxic activity of 26c might be partially through suppressing the phosphorylation of c-Met kinase.