AMG232类似物设计、合成和抗肿瘤活性研究及吡咯酮并吡唑类化合物手性拆分工艺研究

发布时间：2018-03-23 21:29

本文选题：p53-MDM2　切入点：AMG232　出处：《宁夏医科大学》2017年硕士论文

【摘要】：抑癌基因p53是一种在肿瘤发生中起着重要作用的调节因子,被广泛认为是“基因组的守护者”,参与受损细胞的修复和凋亡。MDM2蛋白是p53最重要的负反馈调节因子。MDM2过量表达会导致细胞增殖失控,继而导致肿瘤生长。AMG系列化合物是安进公司报道的哌啶酮类小分子抑制剂,可以通过与MDM2特定位点结合,阻断p53-MDM2相互作用,对肿瘤细胞增殖具有很高的抑制活性。AMG232是其中活性最好的小分子抑制剂之一,分子和细胞水平抑制率都达到了低nM级,目前已进入临床II期试验,有望开发成新的抗肿瘤药物。但是其羧基侧链在体内容易通过葡萄糖醛酸结合途径代谢失活,导致其半衰期较短,成药后可能会给患者造成频繁给药的负担。本课题组拟通过将AMG232羧基侧链改造为酯类,降低其在体内与葡萄糖醛酸结合而代谢失活的能力,延长其半衰期,改善药代动力学性质。设计合成得到15个全新结构的AMG232酯类衍生物。其中化合物7的蛋白结合活性与对HCT116癌细胞系的抑制活性最好,与阳性药相当。另外,我们对AMG232关键中间体的合成路线进行了初步探索,设计打通了一条收率高、反应条件温和的AMG232关键中间体的合成路线。研究发现,NF-κB基因突变激活与决定许多肿瘤进展的慢性炎症息息相关,而且还会诱导肿瘤细胞对多种抗肿瘤药物产生耐药性。我们课题组前期通过虚拟筛选得到一类同时激活p53信号通路和抑制NF-κB信号通路全新结构类型的高活性吡咯酮类化合物,并基于吡咯酮骨架先导物进行了合理药物设计发现了活性更强的吡咯酮并吡唑化合物。机制研究表明,R-异构体能激活p53,并呈剂量依赖关系,同时抑制MDM2的表达。而S-异构体则对p53通路没有明显的作用。对NF-κB信号通路,这对异构体的作用则与p53通路完全相反,S-异构体可以激活磷酸化的IKKα、β、γ而抑制NF-κB的激活,而R-异构体则对NF-κB通路没有影响。为进一步研究光学异构体对活性的影响,我们对吡咯酮类化合物进行不对称合成研究,获得了4对高ee值的R、S-光学异构体。在此基础上,通过体外抗肿瘤活性研究,获得了两种光学异构体的最佳配比,为后续的p53-MDM2与NF-κB信号通路交互协同作用研究打下坚实的基础。
[Abstract]:The tumor suppressor gene p53 is a regulatory factor that plays an important role in tumorigenesis. It is widely regarded as a "guardian of the genome", which is involved in the repair and apoptosis of damaged cells. MDM2 protein is the most important negative feedback regulator of p53. MDM2 overexpression can lead to uncontrolled cell proliferation. The resulting tumor growth. AMG series of compounds are small molecular inhibitors of piperidone reported by Amgen, which can block p53-MDM2 interactions by binding to specific sites of MDM2. AMG232 is one of the best small molecular inhibitors of tumor cell proliferation. The inhibition rate of both molecular and cell level has reached low NM level, and has entered the phase II clinical trial. It is expected to be a new antitumor drug, but its carboxyl side chain is easily metabolized by glucuronic acid binding pathway in vivo, resulting in a shorter half-life. The study group intends to transform the carboxyl side chain of AMG232 into esters so as to reduce its ability of metabolism inactivation by binding with glucuronic acid in vivo and prolong its half-life. To improve the pharmacokinetic properties, 15 novel AMG232 ester derivatives were designed and synthesized. The protein-binding activity of compound 7 was the best and the inhibitory activity was similar to that of the positive drug. The synthetic route of the key intermediate of AMG232 was preliminarily explored and a high yield was designed. Synthesis of key Intermediates of AMG232 with mild reaction conditions. It has been found that the activation of NF- 魏 B gene mutation is closely related to the chronic inflammation that determines the progression of many tumors. Moreover, it can induce tumor cells to develop drug resistance to various antitumor drugs. Our team obtained a class of highly active pyrrolidone compounds that simultaneously activate p53 signaling pathway and inhibit new structural types of NF- 魏 B signaling pathway through virtual screening. The more active pyrrolidone benzopyrazole compounds were found based on the pyrrolidone skeleton lead. The mechanism showed that the pyrrolidone isomer could activate p53 in a dose-dependent manner. At the same time, the expression of MDM2 was inhibited. The S- isomer had no obvious effect on p53 pathway, but on NF- 魏 B signaling pathway, the effect of the isomer was opposite to that of p53 pathway. S- isomer could activate phosphorylated IKK 伪, 尾, 纬 and inhibit the activation of NF- 魏 B. However, R- isomer has no effect on NF- 魏 B pathway. In order to further study the effect of optical isomers on activity, we have studied the asymmetric synthesis of pyrrolidone compounds and obtained 4 pairs of high ee RGS-optical isomers. The optimal ratio of two optical isomers was obtained through in vitro antitumor activity study, which laid a solid foundation for the further study of the interaction between p53-MDM2 and NF- 魏 B signaling pathway.
【学位授予单位】：宁夏医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R914

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