Synthesis And Bioactive Evaluation Of 2-substituted Styryl-4-aminoquinazoline Derivatives

Quinazoline is very important nitrogen-containing heterocycle compound.It presents in a great deal of drugs,especially in antitumor reagent.Its derivatives exhibit divers bioactivity such as antitumor,antibacterial,antiinflammatory and antivirus,and so on.Their syntheses and bioactivities have been always an active research field in medicinal chemistry.This dissertation focuses on the synthesis and bioactive evaluation of 2-substituted styryl-4-aminoquinazoline derivatives.In chapter one,the recent research progress on the bioactivities of quinazoline derivatives was reviewed.In chapter two,the synthesis of 2-substituted styryl-4-aminoquinazoline derivatives was discussed.o-Aminobenzamide reacted with anhydride to give the2-methyl-4-hydroxyquinazoline derivatives 2.Compound 2 condensated with aromatic aldehydes under acidic conditions to provide 2-substituted styryl-4-hydroxy--quinazoline derivatives 3～5.3～5 were further treated with phosphorus oxychloride and then a primary amine to furnish forty-eight 2-substituted styryl-4-amino--quinazoline derivatives 9～11.All target compounds were characterized by NMR and HRMS.In chapter three,the in vitro anti-proliferation of the target compounds against the human bladder cancer cell line（T-24）,the gastric cancer cell line（MGC-803）,the prostate cancer cell line DU145 and PC-3,the lung cancer cell line（A549）,as well as their cytotoxicity to human normal liver cells HL-7702 were evaluated via MTT assay.The results indicated that some of them exhibiting potent anti-proliferation activities against the tested cancer cell lines.Among them,compound 10ah showed the most potency with an IC₅₀ value ranged from 1.73 to 5.48μmol/L against the tested cancer cell lines.Its IC₅₀ value against the gastric cancer cell line MGC-803 as low as 1.73μmol/L.In chapter four,10ah was selected to further investigate the anti-tumor mechanism against MGC-803 cells.The results of spectroscopic and agarose gel electrophoresis assay indicated that 10ah could intercalate into DNA.The cell cycle arrest effects,the apoptosis induction,the effects on mitochondrial membrane potential,intracellular reactive oxygen species（ROS）and calcium concentration,the induction of Caspase-9 and Caspase-3 activation of 10ah on MGC-803 cells were studied via flow cytometry.The results suggested that 10ah could arrest the cell cycle in G2/M phase,induce significant cell apoptosis,break down the mitochondrial membrane potential,increase the level of intracellular calcium concentration and reactive oxygen species（ROS）and activate Caspase-9 and Caspase-3.Western Blot assay was used to detect the expression level of apoptosis-related proteins in 10ah treated MGC-803 cells.The results demonstrated the 10ah could obviously down-regulate the anti-apoptosis proteins Bcl-2 and Bcl-xL,while up-regulating the pro-apoptosis proteins Bax,Bak and Bim.The p53,P-p53（Ser15）,p21,CDK4 andγH2AX were also up-regulated in MGC-803 cells after 10ah treatment.The results of antitumor evaluation in vivo via MGC-803 xenograft tumor model demonstrated that 10ah could significantly inhibit the tumor with tumor growth inhibition（TGI）up to 61.8%and displaying no obvious toxicity.