Design,Synthesis And Antitumor Activity Studies Of Novel Benzo[b]azepine-Chalcone Hybrids

In recent years,the number of deaths caused by cancer is increasing year by year,and it has ranked the second among all human diseases.Although today’s anticancer drugs have made great strides in improving patients’survival time and quality of life.However,there are still high mortality rates of cancer patients,obvious side effects and drug resistance of anti-cancer drugs,which limit their clinical use.Therefore,it is very urgent to find more ideal anti-tumor drugs.Natural chalcone has certain antitumor activity,and it has the advantages of simple structure and easy synthesis.However,low potency and poor cell selectivity limit its druggability.Benzazepine structure is often used as significant constituent part of the tumor-related kinases（PLKI,VEGF-R2,CDKs,and Cyclins）inhibitors to participate in the design of antitumor drugs.Thus,we introduced this structure into the natural chalcone is considered in order to obtain novel antitumor lead compounds with high antitumor activity and high cell selectivity.Based on the combination principle of drug design,30 new benzo[b]azapine-chalconone hybrids were designed and synthesized by hybridize benzo[b]azapine and chalconone,two active pharmacophores.The target products were characterized by melting point,¹H NMR,¹³C NMR and HR-MS（ESI）.The antiproliferative activity of the target compounds against four cancer cells（HGC-27,Hep G2,Pan02 and A549）and one normal cell（GES-1）was evaluated by MTT assay.Most synthetic compounds exhibited potent antiproliferative activity against HGC-27cells(IC₅₀=0.78-20μM).However,they exhibited moderate antiproliferative activities against Hep G2,Pan02 and A549 cell lines(IC₅₀=8.39-35μM).Among them,compound 8b(IC₅₀=0.80μM)and 8d(IC₅₀=0.78μM)gave better antiproliferative activity than cisplatin(IC₅₀=7.38μM)and colchicine(IC₅₀=3.86μM)against HGC-27 cells.Meanwhile compound 8d(IC₅₀=22.77μM,SI=29.19)showed weak cytotoxicity against GES-1 cells compared with compound 8b(IC₅₀=7.40μM,SI=9.25)and cisplatin(IC₅₀=9.51μM,SI=1.29).Furthermore,the effects of compound 8d on HGC-27 cell apoptosis,cell cycle and apoptosis-related proteins were evaluated.The results showed that compound 8d could significantly induce the morphological changes and the number reduction of HGC-27 cells,arrest the cell cycle in the G2/M phase,and induce the apoptosis of HGC-27 cells by increasing the expression of pro-apoptotic protein Bax and decreasing the expression of anti-apoptotic protein Bcl-2.Furthermore,molecular docking assay and EBI competitive assay indirectly demonstrated that compound 8d is a novel tubulin inhibitor binding to colchicine sites.In this paper,the synthesis route of the compound 8d was screened from the factors such as the price of raw materials,the reaction conditions and whether it caused pollution to the environment,and the reaction conditions of the key steps of the synthesis route were optimized.The optimum reaction conditions（catalyst and dosage:Al Cl₃,4eq,solvent:dichloromethane,time:2h）for the key step 5 in the synthesis route 1 were obtained,and the yield reached 45-55%.Finally,a highly efficient,economical,safe and environmentally friendly synthetic route was obtained.