节点文献
若干皂甙和黄酮甙的合成研究
Synthesis of Some Saponins and Flavonoid Glycosides
【作者】 彭文杰;
【作者基本信息】 中国科学院研究生院(大连化学物理研究所) , 有机化学, 2006, 博士
【摘要】 皂甙和黄酮甙广泛存在于天然产物中,它们是许多中草药的活性成分。利用化学合成方法建立活性天然产物类似物分子库,是筛选低毒、高效新型药物的有效手段之一。本论文完成了若干皂甙和黄酮甙的合成研究,着重于建立有效合成葡萄糖醛酸苷齐墩果烷型双糖链三萜皂甙(GOTCAB)和黄酮甙类化合物的新方法,以及解决OWS-1(缺A、B环)类似物关键步骤的合成,为筛选药物先导化合物奠定基础。本论文以齐墩果酸为原料,采用先选择性在28位羧基糖苷化反应,然后3位羟基糖苷化反应,最后氧化伯羟基为羧基的策略,分别以线性操作七步以28%总收率和线性操作九步以26%总收率合成了人参皂甙Ro和皂甙Ⅱ。利用PhSH/imidazole/NMP体系选择性地脱除了槲皮素衍生物4’-OH上的乙酰基,成功的制备了7-O-苄基柽柳黄素;经碱性条件下的相转移糖苷化技术首次合成了柽柳黄素3-O-新橙皮甙和异鼠李素3-O-新橙皮甙,同时发现文献报道的天然产物柽柳黄素3-O-新橙皮甙实际上为异鼠李素3-O-新橙皮甙。利用NaOH (aq.)代替K2CO3 (aq.)碱性体系,溴苷可以继续与受体槲皮素3位氧甙的3’-OH反应,建立了有效合成3,3’双糖链柽柳黄素和槲皮素氧甙的方法,为娑罗子黄酮甙A的全合成提供了技术支持。采用活性较高的Pd(OAc)2-SPhos-K3PO4催化体系,利用Suzuki-Miyaura偶联反应,成功的在槲皮素的4’或3位接上了带有不同基团的芳香环,丰富了黄酮类化合物分子库。成功地构建了反式环和顺式环的OSW-1(缺A、B环)类似物,为这两个目标分子的全合成提供了关键技术。
【Abstract】 Saponins and flavonoid glycosides have been found widely in natural products. They are the major biologically active ingredients in many chinese traditional herbs. Chemical synthesis of active analogous compounds is one of the useful strategies to screen out new low toxic and high effective medicine. In this thesis some saponins and flavonoid glycosides were synthesized with emphasis on establishing the effective synthetic routes of glucuronide oleanane-type triterpene carboxylic acid 3,28-bisdesmosides (GOTCAB) and flavnoid glycosides, and resolving the key synthetic steps of OSW-1 analogues (A-nor and B-nor). This serves as a basis for screening out lead medical compounds.In this thesis Ginsenoid Ro and saponin II were synthesized in linear seven steps (28% overall yield) and nine steps (26% overall yield) started from oleanolic acid. The key features of the synthesis are: attachment of the 28-glucosyl ester before assembly of the 3-O-sugar chain; elaboration of the glucoronide residue at a later stage via the TEMPO-mediated selective oxidation.7-O-Benzyl tamarixetin was produced successfully with PhSH/imidazole/NMP selective removal of the acetyl group on the 4’hydroxy of quercetin derivation. Tamarixetin and isorhamnetin 3-O-neohesperidoside were firstly synthesized under basic phase transfer catalysis (PTC) condition. The natural flavonol glycoside assigned as tamarixetin 3-O-neohesperidoside in the literature should be revised into isorhamnetin 3-O-neohesperidoside.
- 【网络出版投稿人】 中国科学院研究生院(大连化学物理研究所) 【网络出版年期】2007年 04期
- 【分类号】R284
- 【被引频次】3
- 【下载频次】616
- 攻读期成果