阿里山五味子果實新穎三萜類成分之研究

Abstract

本論文主要研究台灣產阿里山五味子 (Schisandra arisanensis Hayata) 果實之丙酮萃取物，並分析鑑定所含的降三萜類成分，共分離得到十個降三萜類化合物。其中包括了六個新化合物，分別命名為arisanlactones A-F (1-6)，以及四個已知化合物，分別是schindilactone D (7)、schindilactone E (8)、pre-schisanartanin A (9)和pre-schisanartanin B (10)。 新化合物1-6為降三萜類，其中化合物1為一新骨架具有5/5/7/9/5-fused pentacyclic環系統，化合物2為wuweiziartane-type骨架，包含一新的合環結構；而化合物3-5為pre-schisanartane-type 骨架，化合物6和7為schisanartane-type骨架。以上所有化合物結構鑑定主要是利用一維及二維核磁共振圖譜 (包括1H-NMR、13C-NMR、DEPT90與DEPT135、1H-1H COSY、HMQC、HMBC、NOESY等實驗)，再加上質譜與各種光譜數據，包括紅外光、紫外光、旋光儀，並且比對過去文獻相關化合物的數據而得。在立體結構解析方面，則是利用NOESY圖譜、分子模型以及X-ray單晶繞射來建立。同時，對化合物1-10的生合成路徑做了推測與討論。

This research focuses on nortriterpenoids isolated from the fruits of Taiwanese medicinal plant Schisandra arisanensis Hayata. Fractionatin of acetone extract by extensive chromatographic analysis afforded six new nortriterpenoids, arisanlactones A-F (1-6), together with four known compounds, schindilactone D (7), schindilactone E (8), pre-schisanartanin A (9) and pre-schisanartanin B (10). Compound 1 belongs to an unprecedented skeleton possessing a 5/5/7/9/5-fused pentacyclic ring system. Compound 2, a wuweiziartane-type skeleton, also contains a new class of fused ring system. Compounds 3-5 are categorized as a pre-schisanartane-type, and compound 6 is a schisanartane-type nortriterpenoid. All the structures of the above compounds were elucidated by 1D, 2D-NMR and Mass, in addition to several physical methods including IR, UV, and single crystal X-ray diffraction analysis, and comparing the spectroscopic data with those in the published papers. The relative configuration of compounds 1-6 was established by NOESY spectra and single crystal X-ray diffraction analysis. Plausible biosynthesis pathway of compounds 1-10 were also discussed.