Solanoeclepin A 之合成研究

Synthetic Studies Towards Solanoeclepin A

莊翔宇(Hsiang-Yu Chuang)

指導教授 ： 汪炳鈞 ； 磯部稔

國立清華大學/理學院/化學系所/博士(2017年)

摘要

本論文描述天然物solanoeclepin A之合成研究，包括設計並合成solanoeclepin A右邊D, E, F三個環之架構。本論文敘述數個關鍵之碳碳鍵合成反應以合成天然物solanoeclepin A中的四圓環架構中間體 其中關鍵反應包括(1) [2,3]-Wittig 重排反應 (2) 1,4-加成反應 (3) 三氟乙酸汞參與之水合/環化反應 (4) 以二錪化釤的進行含環丁烷架構之合成的研究

關鍵字

天然物合成 ； 環化反應 ； 二錪化釤 ； 環丁烷

並列摘要

Solanoelcepin A, a triterpenoid hatching stimulant for potato cyst nematode (PCN; Globodera rostochiensis and G. pallida), was first isolated from potato root by Mulder in 1986, and its structure was later determined by Schenk in 1999. As natural hatching stimulus for potato cyst nematode, solaoneclepin A have emerged to be a potential solution for yield loss of potato production over the world. The important
biological activity and its complexity of structure have intrigued the interest of synthetic chemists to challenge the total synthesis.

This thesis describes the synthesis of an cyclobutane intermediate, which was prepared from ent-Hajos-Parris ketone . The synthesis consists of four key C-C bond formation reactions, including (i)a [2,3]-Wittig
rearrangement, (ii) a Michael addition, (iii) a Hg(OTFA)2-mediated oxymercuration/aldol reaction, (iii) the synthesis of cyclobutane intermediate was achieved through a SmI2-mediated radical cyclization, and was carried out in 20 linear synthetic steps with 2.2% yield.

並列關鍵字

cyclobutane ； samarium diiodide ； cyclization ； natural product ； total synthesis

參考文獻

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