【作者】 周燕；

【导师】 李庶心；

【作者基本信息】 广西医科大学 ， 药物化学， 2012， 硕士

【摘要】 癌症是导致人类死亡的一个主要原因，仅次于心脑血管疾病。传统的化疗药物因为缺乏对药物作用靶标的选择性，在杀死癌细胞的同时也会杀死很多正常的细胞并引起正常组织的损伤，而且通常会产生比较严重的不良反应，对恶性肿瘤的治疗仍未达到满意的效果。在临床的治疗中，肿瘤细胞的多耐药性也成为化疗失败的一个主要原因。基因有序的转录调控是机体细胞维持正常功能的前提,如果基因转录调控功能紊乱，细胞就可能发生癌变。而组蛋白的乙酰化状态对于基因转录具有重要调控作用，因此与肿瘤的产生、增殖以及致癌基因和肿瘤抑制基因的表达水平有着密切的关系。而组蛋白的乙酰化状态由两类酶决定：组蛋白乙酰转移酶（HAT）和组蛋白去乙酰化酶（HDAC）。在正常生理状态下，这两类酶对组蛋白乙酰化作用的调控处于平衡状态，而细胞在发生转化的状态下，HDAC的活性明显增强，使得原有基因表达平衡状态被打破，导致一些影响细胞增殖和调控细胞周期的分子表达失衡，进而导致细胞恶变。组蛋白去乙酰化酶抑制剂能够有效抑制肿瘤细胞生长并促进分化、诱导细胞调亡，并能够避免肿瘤产生耐药性，具有选择性高、特异性强、高效低毒的优点，为肿瘤治疗提供了新方向。组蛋白去乙酰化酶抑制剂主要有两类：异羟肟酸类和苯甲酰胺类。与异羟肟酸类HDAC抑制剂相比，苯甲酰胺类具有选择性高、毒性低、耐受性好的优点。目前进入临床研究的苯甲酰胺类药物有CI994、MS-275、CS055、MGCD0103。其中MGCD0103是另一个具有口服生物利用度的HDAC抑制剂，具有较高的抗癌活性和选择性，但其水溶性较低，大鼠的物利用度为47%，狗的生物利用度为1%-90%，变异系数也比较大。我们选择MGCD0103作为先导化合物，利用非经典的电子等排原理对其进行结构改造，结合本实验室以往的研究经验，用吡嗪、取代苯基，苯并噻吩等替代吡啶环，其水溶性还是比较差，生物活性改变不大，药代动力学试验结果也不理想。介于很多药物的头部都含有稠杂环基团，它们可作为应力活化蛋白激酶、白介素-1受体相关激酶、细胞周期蛋白依赖性激酶、磷酸肌醇3-激酶等抑制剂及苯并二氮杂卓受体配体，而且是很好的疏水性基团，具有较好的、潜在的药用价值，因此我们用稠杂环基团或取代的稠杂环基团替代MGCD 0103中的吡啶基团，改善酶结合区的疏水性，增强它与靶标的结合，保持连接区平面结构或者增加连接区的长度，在酶抑制区保留其活性部位N-(2-氨基苯基)苯甲酰胺结构，或在2′-氨基对位或间位引入氟原子，增强氨基与羧酸之间的缩合，提高氨基的稳定性，并考察其对活性的影响，设计合成了12个新颖的化合物，并通过1H-NMR验证其结构。我们采用人乳腺癌细胞系MCF-7对目标化合物进行体外活性评价。评价结果显示，进行测试的8个化合物都体现出了一定的对人乳腺癌细胞系MCF-7的生长抑制作用，其中化合物其中7个化合物的活性比阳性对照物MGCD0103的活性高，尤其是化合物2、3的活性最好，其活性几乎是MGCD0103六倍。更多还原

【Abstract】 Following cardiovascular disease, cancer is currently the second majorcause of death in the world. Because of lacking of the selectivity to the drugtarget,traditional chemotherapeutic drugs can kill many normal cells anddamage to normal tissue, even to some serious adverse reactions when they killthe cancer cells,so it has not yet reached satisfactory results. In the clinicaltreatment , resistance of multidrug in tumors has also become the main reasonof chemotherapy failure.Transcriptional regulation of gene is the premise which maintains normalfunction of the heathy cells. When the transcriptional regulation is dysfunctional,the cell may become cancerous. The acetylation status of histone play animportant regulatory role in gene transcription, so it has a close relationshipwith the generation and proliferation of the tumor and expression levels ofoncogene and tumor suppressor gene. Histone acetylation status is decided bythe two types of enzymes: histone acetyltransferase activity (HAT) and histone deacetylase (HDAC). Under normal physiological conditions, the regulation oftwo types of enzymes for histone acetylation is in a state of equilibrium. Whenthe transformation occurred, HDAC activities servously increased which makesHDAC and HAT out of balance and impact cell proliferation and cell cycleregulation molecule expression imbalance and cell deterioration.Histone deacetylase inhibitors because they can effectively inhibit tumorcells proliferation and promote differentiation, induce apoptosis, avoid tumorresistance and have the advantages of high selectivity, specificity, efficiency andlow toxicity, is a new direction for cancer treatment. Histone deacetylaseinhibitors contain two categories: hydroxamic acid and benzamide. Benzamidehave the advantage of high selectivity, low toxicity and good tolerabilityadvantages compared with the hydroxamic acids . Some benzamide drugs haveentered into clinical phase, such as CI994, MS-275,CS055 and MGCD0103.MGCD0103 is another Histone deacetylase inhibitor with oral bioavailabilityand has high anti-cancer activities and selectivity, but its bioavailability for thedog and rat are 1-90% and 47%,Coefficient of variation is big.Based on MGCD0103 as the leading compound, we have used theprinciple of non-classical electronic emission to transformat the structure ofMGCD0103. According to the previous studies in our work, we replacepyrazine, substituted phenyl, benzothiophene or their derivative to pyridinering.,but their water-solubility and biological activities is bad, pharmacokineticresults are not satisfactory too.The heterocyclic groups can be used asstress-activated protein kinase, interleukin-1 receptor-associated kinase,cyclin-dependent kinase, phosphatidylinositol 3 - kinase inhibitors ,benzodiazepine receptors and benzodiazepine ligands, so they are contained in the head of some drugs, they are also good hydrophobic groups and have goodpotential medicinal value. So we took heterocyclic groups or substitutedheterocyclic groups instead of pyridyl group of MGCD0103;improved thehydrophobicity of the enzyme binding sit, increased the combination with thetargets, and maintained the structure of the connection area of the planarstructure or increased the length of the connection area and kept its active siteN-(2 - aminophenyl) benzamide in the enzyme inhibition; pulled fluorine atomsin meta position or ortho position of 2’-Amino; enhance the condensationbetween the amino and carboxylic acid, to improve the stability of the aminoand to examine its impact on the activity. We designed and synthesized 12 newcompounds, and their structures had been verified by 1H-NMR.We used MCF-7 to evalute the activities of target compounds in vitro . Theresults showed that eight of them have some inhibition activity. There are seventarget compounds showed better anti-activity in vitro than MGCD0103, especia-lly compound 2,3 showed the best activity, and their activities are almost theMGCD0103 six times.更多还原