Design,Synthesis And Anticancer Activity Studies Of Quinazolines Egfr Inhibitors

Cancer is the"first killer"that harms human health.In recent decades,researchers have been working to develop highly effective,low-toxic therapeutic drugs for various cancers.Studies have shown that EGFR is overexpressed in a variety of cancers,such as lung cancer,cervical cancer,breast cancer.Epidermal Growth Factor Receptor?EGFR?signaling pathway is one of the hotspot signaling pathways involved in the study,which regulates important biological processes in the development of many tumors,including promoting cell proliferation,differentiation,protein synthesis,and metastasis.In this paper,through reviewing and analyzing the EGFR inhibitors that have been listed or are in clinical research in the past decade and their EGFR-associated kinases complex crystal structures,the structure-activity relationship of these inhibitors was summarized.At the same time,combined with the excellent clinical manifestation of the first-generation and second-generation EGFR inhibitors containing quinazoline structure and the extensive use of quinazoline structure in antimalarial,anti-inflammatory,anticonvulsant drugs,etc.,the quinazoline structure was choosed to be a mother nucleus.A total of 83 target compounds containing quinazoline structures were designed and synthesized.The in vitro antitumor activity of all target compounds for the tumor cells?H1975,A549,MCF-7,Hela?overexpressing EGFR was assayed by MTT.First,combined with the research progress of covalent inhibitors and our previous research on small molecule inhibitors containing aryl carbamide,we proposed to use aryl carbamide unit as a targeting group.46 Compounds containing aryl carbamide structure were designed and synthesized.Most of the target compounds exhibited moderate to excellent in vitro antiproliferative activity against selected cancer cell lines.Among them,16 compounds showed significant antiproliferative activity against H1975,a cell with high expression of EGFR^L858R/T790M858R/T790M mutiation.These compounds were subjected to kinase inhibitory activity studies against EGFR^wt and EGFR ^L858R/T790M.The results showed that the compounds exhibited less than 10 nM IC₅₀0 for EGFR^wtt kinase inhibitory activity,and the inhibitory activities of eight compounds against EGFR ^L858R/T790M kinase were below 0.5?M.Among them,compounds WCL-6 and WCL-36 had the most significant inhibitory activities,with an IC₅₀ of 0.4 and 6.3 nM for EGFR ^wt and 107.4and 8.4 nM for EGFR ^L858R/T790M,respectively.In addition,the compound WCL-36reached the same level as the positive control drug Afatinib.In order to reduce the toxic effects of Afatinib due to the Michael receptor,further exploration about the effects of different targeting groups on toxicity/activity was carried out.In this paper,37 target compounds were designed and synthesized from three different directions.First,we investigated the quinazoline C-6 position as a targeting group by introducing a thiourea group instead of the Michael acceptor.At the same time,according to the biopharmaceutical drug design principle,the structure of urea was introduced to explore the effect on anti-proliferative activity in vitro.Secondly,after molecular docking and crystal structure analysis,we moved the Michael acceptor from C-6 position to the quinazoline 6 position while retaining the urea unit at the 7-position of quinazoline,and targeted it to the Cys797residue using Linker.Finally,a new five-membered heterocyclic ring was used in place of the aniline group at the 4-position of the quinazoline.Combined with the researchers'transformation of the Michael receptor,it was replaced differently to achieve the desired results.Most of these compounds show good inhibitory effects on selected cells.14 compounds exhibited excellent inhibitory effects on H1975 cells with an IC₅₀ between 1.59±0.35 and 15.37±5.34?M.All compounds were found to have an inhibitory activity against EGFR^wt kinase of less than 4 nM,and the inhibitory activity of the four compounds against EGFR^L858R/T790M kinase was below100 nM.Among them,the compound WCL-56 had the most significant kinase inhibitory activity against EGFR ^wt(IC₅₀=0.8 nM)and EGFR^L858R/T790M(IC₅₀=2.7nM).This inhibitory activity reached an equivalent level of Afatinib(IC₅₀=0.6 nM,IC₅₀=3.5 nM).In addition,according to the cytotoxicity and enzyme activity results of the compounds,the above-mentioned highly active compounds were further studied,including apoptotic cycle experiments of flow cytometry,AO staining experiments and molecular docking studies.All the results of its structure-activity relationship provide the basis for the discovery of novel EGFR tyrosine kinase inhibitors.It points the way for future compound optimization.