Design,Synthesis And Biological Evaluation Of B-RAF^V600E Inhibitor

The RAS/RAF/MEK/ERK cell signal transduction pathway plays an important role in human physiological,pathological conditions and participates in the process of cell proliferation,differentiation and apoptosis.RAF kinase is involved in the RAS/RAF/MEK/ERK cell signal transduction pathway,and its abnormal activation is an important factor in the development of cancer.The RAF kinase family has three members:A-RAF,B-RAF,C-RAF.The mutagenesis of B-RAF kinase is the cause of various tumor formation and development,among of the mutagenesis,B-RAF^V600E,which a valine?V?was replaced with glutamic?E?,is the most common type.To discover new and effective anti-tumor drugs,B-RAF^V600E inhibitor has been a hot and a variety of B-RAF^V600E600E inhibitors have shown tremendous breakthrough efficacy in clinical practice during years of study.Most patients have good suppression of tumor growth in the initial stage of treatment,however,some patients may suffer drug resistance after long-term administration.In the previous studies,some drug resistance mechanisms have been confirmed by preclinical and partial clinical data.As the mechanism of resistance to B-RAF^V600E inhibitors is constantly being discovered and elucidated,we can believe that this will accelerate the development of new therapeutic strategies such as combination therapy,intermittent dosing and individualized treatment more quickly and better.It also provides new ideas for the development of multi-target anti-tumor drugs.To discover new anti-tumor drugs and find the interaction mechanisms of new ligands and the target,Sorafenib is selected as a lead compound,and 17 new compounds were synthesized designed by using computer-aided drug design approach and structurally-based drug design approach.The kinase inhibition assay results showed that compounds 4f,4g and 4i had significant inhibitory activity against B-RAF^V600E with IC₅₀ values of 4.965?M,2.505?M and 6.473?M,respectively.Beside B-RAF^V600E kinase inhibition assay,some other typical kinases in the process of cancer development were also tested to evaluate the specificity of these three compounds,and the results showed that compounds 4f,4g and 4i had no inhibition activity against these typical kinases.Our data preliminary demonstrated the selectivity of compounds 4f,4g and 4i for inhibition of B-RAF^V600E kinase.In addition,we also evaluated these three compounds on the proliferation of colon cancer cell colo205,and all compounds showd inhibitory effect on the assays.Combined with the data of kinase inhibition experiments,it can be hypothesized that these three compounds inhibit the proliferation of colo205 by inhibiting B-RAF^V600E600E kinase.Above all,the data in this thesis provides experimental basis for utilization and the further development of new B-RAF^V600E600E kinase inhibitors.