C17-氮杂环修饰的黄体酮衍生物的合成、抗癌活性及其机制研究

Steroidal compounds exhibit numerous forms of biological activity. To obtain higher active lead drugs, structural modification of steroids is now still one of the main ways in the drug discovery and development process.Progesterone is one of the most important hormones of the steroidal pregnane series. We found that C-17 pyrazolinyl derivatives 4a-e of progesterone had shown moderate anticancer activities against NCI H460, HeLa and HepG2 cells. This subject will be done with progesterone as starting material. After A-ring modification whereby dehydrogenation of C-1-C-2, introduced a chlorine atom at C-4 position, stereoselective reduction of C-3- carbonyl to -β-hydroxy of progesterone, the synthesized 21E-benzylidene derivatives formed the C-17 N-heterocyclic derivatives through ring-closure reaction. In addition, the structure of all derivatives will be elucidated by spectral analysis, and their anticancer activities will be investigated through cytotoxic activity screening, and their structure-activity relationships (SAR) will be analyzed, so as to find new lead compounds with high activity. Moreover, the primary anticancer mechanisms will be also discussed using molecular biology techniques including apoptosis and cell cycle assays as well as in vivo animal model. These data will provide experimental evidences of chemistry and pharmacology for the research of new anticancer drugs.

甾体化合物具有多样的生物活性，对甾体结构作进一步的结构修饰或改造，使其成为活性更高的先导药物，是当今新药创制的主要途径之一。黄体酮是一种重要的甾体孕激素。前期细胞毒活性结果表明，C17-吡唑啉环修饰的黄体酮类衍生物4a-e对三株人癌细胞（NCI H460、HeLa和HepG2）增殖具有中等抑制活性。本项目拟以黄体酮为底物，分别先对A-环从1,2-位引入双键，4-位引入氯原子和3-位选择性还原为-β-羟基等方面进行修饰，在合成21E-苯亚甲基黄体酮衍生物后再向苯环的4′-位分别引入酰胺基、磺酰胺基和脲基等药效团，接着通过关环反应得到C17-氮杂环修饰的黄体酮类衍生物。运用波谱技术对衍生物结构进行鉴定，借助细胞毒活性筛选实验分析其构效关系，以期发现高活性衍生物，进而采用细胞周期、细胞凋亡及动物体内模型等实验探讨高活性化合物的抗癌作用机制，为新型抗癌药物研究提供化学数据和药理学理论依据。

本项目以甾体孕激素——黄体酮为起始化合物，通过对A-环从1,2-位引入双键，4-位引入氯原子等方面进行修饰，接着通过关环反应得到多个系列的C17-氮杂环修饰的黄体酮类衍生物，扩充了黄体酮类衍生物库，共合成出95个新化合物。体外抗癌构效关系实验结果表明：1) 4-位氯原子的引入可降低其活性；2）向C17-氮杂环上引入取代苯基对提高细胞毒活性未有显著影响。进一步的抗癌机制研究发现，高活性衍生物可诱导细胞凋亡，细胞凋亡率与处理时间呈正相关。通过检测Caspase活性及相关凋亡蛋白的变化确定，其是通过诱导线粒体通路发生凋亡。这些结果为新型基于甾体药物分子的发展提供了基础数据和理论依据。在该项目的资助下，已发表SCI论文6篇；协助培养博士研究生1名，硕士生2人。