【作者】 赵玉明；

【导师】 涂永强；

【作者基本信息】 兰州大学 ， 有机化学， 2010， 博士

【摘要】 本论文针对一些复杂多环生物碱开展了一系列合成方法和全合成研究,并取得了一系列重要的研究成果,主要包括以下四部分：一、完成了百部胺类生物碱stemonamine的首次全合成研究。从烯酮1-57出发,以本小组发展的四氯化钛促进下的α-硅醚环氧叠氮化合物参与的semipinacol重排／分子内的Schmidt串联反应和Dieckmann缩合为关键步骤,经13步化学转化,最终以3.7%的总收率,实现了stemonamine的首次全合成。二、百部胺类生物碱stemonamine和三尖杉碱cephalotaxine的全合成研究。以对称2-季碳-1,3-叠氮二酮的分子内Schmidt反应为关键步骤,实现了stemonamine和cephalotaxine高级中间体2-44和2-56的合成,发展了一条合成此类生物碱的普适性的合成路线。三、从氯代烯酮和叠氮化钠出发,一锅法制备氨基烯酮以及在生物碱全合成中的应用。首次发现了反应温度对叠氮烯酮热反应产物的影响,首次获得该类反应中N,N,N-三唑中间体的X-ray单晶衍射结构,对两类底物(芳基氯代烯酮和非芳基氯代烯酮)的反应历程进行了探讨。并以该反应为关键步骤,实现了生物铖hexahydroapoerysopine和cephalotaxine的形式合成。四、生物碱norphine不对称全合成的尝试。本部分试图以本小组近年来发展的semipinacol重排反应为关键步骤实现morphine中季碳中心的构建,这一阶段的工作虽然没能得到预想的semipinacol重排前体,但使我们对复杂多环生物碱的合成有了更深的理解。更多还原

【Abstract】 The total synthesis of alkaloids is one of the important fields of organic chemistry. This thesis finished some studies towards the total synthesis of bioactive polycyclic alkaloids, and correspondingly a series of importantly progressive results were achieved. This thesis consists of the following four parts:1. A concise and efficient total synthesis of stemonamine was achieved for the first time in 13 steps from the known compound 1-57 in an overall yield of 3.7%, featuring a tandem semipinacol rearrangement/Schmidt reaction and a Dieckmann condensation.2. Simple and efficient formal total syntheses of stemonamine and cephalotaxine were achieved via a facile intramolecular Schmidt reaction of symmetric azido dione precursor. By use of this key reaction, known intermediate 2-44 and 2-56 were obtained through limited chemical transformation. This concise Schmidt reaction may be applicable in other alkaloids syntheses.3. A new one-pot procedure for the synthesis of aminoenone from chloroalkyl enone and sodium azide was designed and demonstrated. Two type’s substrates (aryl chloroalkyl enones and non-aryl chloroalkyl enones) were investigated. Meanwhile, we found that reaction temperature has a strong effect on reaction product. A presumed triazoline intermediate in this reaction process was obtained and confirmed by a single-crystal X-ray analysis for the first time. As the application of this methodology, the formal synthesis of polycyclic alkaloid hexahydroapoerysopine and cephalotaxine were also achieved through limited normal chemical transformation.4. Synthetic studies on the asymmetric total synthesis of morphine. By use of semipinacol rearrangement, we have made an attempt to constract the key quaternary unit in morphine. Despite, we could not obtain the desired rearrangement precursor, this investigation made us have a further understand on the synthesis of this alkaloid.更多还原