Screening And Biological Evaluation Of Novel Anti-Vemurafenib-resistant Tumor Agents Based On Dihydropyrazole Skeleton

As an effective target for treating mutant tumors,BRAF inhibitors has successively developed as a variety of anticancer agents.Although those inhibitors have achieved significant clinical effects,new challenge have arisen due to the rapid development of drug resistance in patients after administration of BRAF selective inhibitors.Therefore,it is necessary to develop new anticancer agents that overcome drug resistance.As an important nitrogen-containing five-membered heterocyclic compound,dihydropyrazole has strong biological activities,such as anticancer,antibacterial,antiviral,etc.,and has become a hot spot in recent years.This topic is based on potential drug resistance mechanisms,especially overexpression of the PI3K/AKT/m TOR signaling pathway.Using the"combined pharmacophore"design strategy,the PI3K pharmacophore that plays an important role in the binding model was introduced at the N-1 position of 2-pyrazoline to establish a compound library containing 2-pyrazoline structure.According to literature reports,anti-Vemurafenib-resistant tumor cell lines A375^R10and Colo205^R17 were established.The CCK-8 method was used to screen highly effective anti-resistant tumor cell lead compound library synthesized earlier by the research group.After further structural modification,24 dihydropyrazole sulfonamide derivatives were synthesized.The synthesized compounds were confirmed by ¹H NMR,¹³C NMR and HRMS,and the configuration of a compound was determined by XRD.Compound E14(A375^R10 IC₅₀=20.93?M and Colo205^R17 IC₅₀=3.25?M)was screened for anti-proliferative activity in vitro and evaluated for biological activity.Kinase activity results indicate that potential inhibitors of PI3K?.The results of cell cycle and apoptosis experiments showed that compound E14 induced Colo205R¹⁷ cell arrest in a dose-dependent manner to induce early apoptosis of cells in G1 phase.The mechanism of apoptosis was studied by Western blotting,and it was found that compound E14 increased the cleavage levels of caspase-3,caspase-9 and PARP in cells in a dose-dependent manner.