Design,synthesis And Biological Evaluation Of Anti-melanoma Agents Based On Pyrazole Moiety

Malignant melanoma is one of the most aggressive cancer type.Almost 50% of metastatic melanoma patients harbor BRAF mutation which induce the hyper-activation of mitogen-activated protein kinase(MAPK)signaling pathway.Since 2011,BRAF inhibitors exhibited strikingly clinical benefit in patients with BRAF-mutant melanoma.Unfortunately,the therapeutic effects are often temporary,most patients who initially respond are acquire resistance within 1 year.The resistance mechanisms are varied and can be classified as MAPK signaling pathway reactivation-dependent and-independent mechanisms.The elucidation of resistant mechanisms provides new insights into strategies for overcoming resistance.The purpose of this study was to select the BRAFV600 E inhibitors with a new structure and the BRAF/PI3 K dual target inhibitors with a new mechanism to overcome resistance,designing and synthesizing pyrazole derivatives(26 compounds)and dihydropyrazole derivatives(24 compounds)by using CADD strategy.The raw materials were easy to obtain,the synthetic routes were simple and the yields of target compounds were high by the synthetic route selection and process optimization.The structures and configurations of the target compounds were characterized by 1H NMR,13 C NMR and MS.Finally,the biological evaluation is tested,mainly including in vitro BRAFV600 E inhibitory activities,antiproliferative activities of A375 human melanoma cells and the specificity for mutant BRAF were assayed.First,it was found that the1H-pyrazole-4-urea derivatives FN1-FN13 inhibited BRAFV600 E more potently than corresponding amine derivatives FA1-FA13 and compound FN10 displayed the most potent BRAFV600 Einhibitory activity(IC50=0.066μM).Then,antiproliferative activities of title compounds were determined using a MTT assay with A375 human melanoma cells,It was observed that compounds,which have potent BRAFV600 E kinase inhibitory activities,displayed the strongest cytotoxic activities against mutant BRAF-dependent A375 cells.Comparing the IC50 data of FN12 and FN13 between the inhibition of WM1361 and A375 cells,indicating a specificity of the compounds for mutant BRAF-driven cell proliferation.