20-去氧巨大戟醇酯衍生物合成及其构效关系研究

	20-去氧巨大戟醇酯衍生物合成及其构效关系研究
	张翠珊
导师	邸迎彤
关键词	20-去氧巨大戟醇酯，自噬，结构修饰，构效关系 20-Deoxyingenane esters, Autophagy, Structural modification, SAR
摘要	巨大戟醇酯是具有多元醇结构单元的二萜，与PKC内源性配体二酰甘油（DAG）结构类似，也是PKC的激动剂。本课题组前期分离得到了一系列20-去氧巨大戟醇衍生物，发现这类化合物能够激活PKCα和δ，进而促进溶酶体发生，机制上同样是模拟DAG结构与PKC的调节亚基结合。20-去氧巨大戟醇酯类化合物没有明显的细胞毒以及促炎作用，因此，在治疗AD等神经退行性疾病方面具有重要的应用前景。但是天然分离得到的20-去氧巨大戟酯类化合物较少，有关其酰基取代基及羟基的数量、种类对生物活性的影响并不清楚。为了探究该类化合物的构效关系并且获得活性更优的自噬诱导剂，本论文以20-去氧巨大戟醇（20-deoxyingenol）及其衍生物HEP14（20-deoxyingenol-5β-O-angelate）和HEP15（20-deoxyingenol-3β-O-angelate）为基础，围绕20-去氧巨大戟醇关键活性位点3、4、5位进行结构修饰，设计合成了一系列衍生物，并开展了相关生物活性的研究。本文第一章对巨大戟烷类化合物的药理作用、结构修饰、构效关系研究进展进行综述，对自噬相关概念和机制进行介绍。本文第二章阐述20-去氧巨大戟醇衍生物的设计、合成及活性测试结果。以前期从南欧大戟分离获得的三个主要成分20-去氧巨大戟醇、HEP14和HEP15为底物，合成了单酰基取代、双酰基取代及其他修饰的衍生物共50个，其中49个为新化合物，以探索取代基种类和数量对激活自噬的影响。对其初步的构效关系总结如下：（1）屏蔽3位和4位羟基且5位引入氨基酸酯对诱导自噬有利；（2）3位酰化或者5位酰化对活性的影响相差不大；（3）双酰化衍生物中，引入吡啶基和乙酰基对活性不利，丙酰基和特戊酰基可以促进自噬。本文第三章针对前期发现的具有较强自噬诱导活性的化合物30，开展了初步机制研究。发现该化合物能够增加自噬相关蛋白LC3-II/I比值，促进LAMP1、CTSB表达和SQSTM1降解，这表明化合物30可以通过促进溶酶体发生诱导自噬。随后的分子对接研究表明，化合物30可模拟DAG，与PKCδ的调节亚基结合，因此化合物30诱导自噬的作用可能与PKC相关信号通路有关。但是化合物30与以往的PKC激动剂结构不同，其与PKC结合的片段是5位具有氨基酸酯侧链，这表明化合物30可能是一类新型PKC激动剂。综上所述，本研究通过结构修饰发现了一个新型自噬诱导剂并初步探讨了20-去氧巨大戟醇酯的构效关系，为巨大戟烷型二萜的开发利用和自噬相关疾病先导化合物的发现提供了新思路。; Ingenol ester is a type of diterpene with an esterification of free polyol, and is activator of PKC like DAG (diacylglycerol). A series of 20-doxyingenol esters have been isolated by our group and exhibit autophagy-inducing activity via activating PKCα and δ, which like DAG. These compounds also exhibit anti Alzheimer's disease (AD) in mice. Additionally, 20-doxyingenol esters do not display cytotoxicity and pro-inflammatory effects compared to ingenol esters. Therefore, these compounds display high potential to anti neuroregenerative diseases such as AD. However, it is unclear that the relationship between the acylation degree and types of acyl groups of 20-deoxyingenol and their biological activity. For the purpose of fully development of these compounds, it is very essential to elucidate the SAR, based on that more efficient autophagy inducers could be gained. Thus, we designed and synthesized a series of 20-deoxyingenol derivatives based on 20-deoxyingenol, HEP14 (20-deoxyingenol-5β-O-angelate) and HEP15 (20-deoxyingenol-3β-O-angelate). The first chapter summarizes the three aspects of ingenane diterpenoids including biological activity, structural modification, SAR and describes the mechanism of autophagy and three types of autophagy. The second chapter describes the design, synthesis and biological evaluation of derivatives. We have used 20-deoxyingenol, HEP14 and HEP15 as substrates to synthesize 50 compounds, of which 49 are never reported before. And we study the effects of amounts and types of acyl group on autophagy-inducing activity. The biological assay results demonstrated that: (1) amino acid esters at C5 while C3-OH and C4-OH shielded are favorable for activity; (2) the acyl group at C3 or C5 has little difference in activity; (3) pyridyl and acetyl groups are harmful to autophagy and propionyl and pivaloyl are favorable among diacylated derivatives. The third chapter describes the preliminary mechanism study of compound 30 which significantly induce autophagy in activity screening. We found compound 30 could increase the protein level of LAMP1, CTSB, TFEB and LC3-II:LC3-I, and stimulate the degradation of SQSTM1 in a dose-dependent manner. All these results implicate that 30 can enhance autophagy-lysosome system by inducing lysosome biogenesis. Further, 30 could bind to the regulatory moiety of PKCδ with two hydrogen bonds which is similar to DAG. We inferred that 30 might interact with PKC to possess autophagy-inducing activity. In addition, dislike DAG, the fragment that interact with PKC is amino acid ester. Therefore, we inferred that 30 could be a new class of PKC activator. In summary, this study reported a novel autophagy inducer and discussed SAR of 20-deoxyingenol, providing evidences for the further rational design of 20-deoxyingenol and for the development of lead compound to anti-autophagy related diseases.
语种	中文
	2022-05
学位授予单位	中国科学院大学
文献类型	学位论文
条目标识符	http://ir.kib.ac.cn/handle/151853/75128
专题	昆明植物所硕博研究生毕业学位论文
推荐引用方式 GB/T 7714	张翠珊. 20-去氧巨大戟醇酯衍生物合成及其构效关系研究[D]. 中国科学院大学,2022.

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