本論文主要研究台灣產軟珊瑚Xenia umbellata Lamarck與柳珊瑚Junceella juncea Pallas、Junceella fragilis Ridley雙萜類成分，分離得到十二個雙萜類化合物，另外得到一個倍半萜類化物。
由軟珊瑚X. umbellata Lamarck中分離出五個天然物，包含了兩個新的xenicane 類天然物，將其命名為xenibelatols A-B (1-2)與三個已知化合物7,8-oxido-isoxeniolide (3)、9-hydroxyxeniolide-F (4)、xenitorin A (5)。由柳珊瑚J.juncea Pallas分離出一個新的briarane類天然物，命名為juncenolide H (6)。由柳珊瑚J. fragilis Ridley中分離出七個天然物，包含了四個新的briarane類天然物，將其命名為flajunolides A-D (7-10)與三個已知化合物junceellolide E (11)、umbraculolide A (12)、11α,20α-epoxy-4-deacetoxyjunceellolide D (13)。
新化合物1,2與6-10分別具有xenicane與briarane的骨架。有關這些新化合物的結構解析是利用一維與二維核磁共振光譜與各種物理性質(包括旋光、紫外光譜、紅外光譜、質譜)配合比對相關文獻來決定。
化合物1-4分別是幾何學上的異構物，僅差異在側鏈上，側鏈的幾何學直接影響到H-12、H-13、H-14跟C-3(carbonyl group)空間上的距離，於是會產生anisotropic effects而造成1H-NMR化學位移的改變。
化合物6-10在C-2、C-9、C-12、C-14都含有乙醯基的取代，在特定位置的NMR化學位移會因為briarane骨架上的差異而有相當程度的變化。
細胞毒殺活性方面，化合物5對人類口腔癌細胞(KB)與人類結腸癌細胞(WiDr)，具有中等細胞毒殺活性，ED50分別為5.9與9.9 μg/ml。

This research focuses on diterpenoids from Taiwanese soft corals Xenia umbellata Lamarck, Junceella juncea Pallas and Junceella fragilis Ridley. Twelve diterpenoids in addition to one sesequiterpenoid were isolated.
Our investigation of the soft coral X. umbellata Lamarck afforded five natural products, including two new xenicane diterpenes, xenibelatols A-B (1-2), together with two known xenicane diterpenes, 7,8-oxido- isoxeniolide (3), 9-hydroxyxeniolide-F (4), and a cadinene sesequiterpene, xenitorin A (5). Chemical investigation of the gorgonian J. juncea Pallas, has resulted in isolation of a new briarane diterpene, juncenolide H (6). Continuing our investigation of the gorgonian J. fragilis Ridley, we isolated seven briarane diterpenes, including four new briaranes, flajunolides A-D (7-10), along with three known briaranes, junceellolide E (11), umbraculolide A (12), 11This research focuses on diterpenoids from Taiwanese soft corals Xenia umbellata Lamarck, Junceella juncea Pallas and Junceella fragilis Ridley. Twelve diterpenoids in addition to one sesequiterpenoid were isolated.
Our investigation of the soft coral X. umbellata Lamarck afforded five natural products, including two new xenicane diterpenes, xenibelatols A-B (1-2), together with two known xenicane diterpenes, 7,8-oxido- isoxeniolide (3), 9-hydroxyxeniolide-F (4), and a cadinene sesequiterpene, xenitorin A (5). Chemical investigation of the gorgonian J. juncea Pallas, has resulted in isolation of a new briarane diterpene, juncenolide H (6). Continuing our investigation of the gorgonian J. fragilis Ridley, we isolated seven briarane diterpenes, including four new briaranes, flajunolides A-D (7-10), along with three known briaranes, junceellolide E (11), umbraculolide A (12),11α, 20α-epoxy-4-deacetoxy junceellolide D (13).
The new compounds 1,2 and 6-10 possess xenicane-type and briarane-type skeletons respectively. The structures of new compounds were determined by 1D-, 2D-NMR spectroscopic analysis and physical methods such as optical rotation, UV, IR, mass spectrum, as well as comparison with the spectroscopic data reported for related compounds.
Compounds 1 and 2 are geometric isomers of compounds 3 and 4. The only difference between them resides in the side chain. The geometry of the side chain influenced the relative spatial proximity of H-12, H-13, H-14 to the carbonyl at C-3, and consequently the extent to which these
protons are subjected to the anisotropic effects of the carbonyl.
Compounds 6-10 have acetyl groups at C-2, C-9, C-12, C-14 positions. Because of structural difference appears in briarane skeleton, they showed different chemical shifts in specific positions.
Biological activity test，revealed that compound 5 exhibited moderate cytotoxic activity against KB and WiDr cancer cell lines with ED50 values at 5.9 and 9.9 μg/ml respectively.

壹、緒論
一.前言1
二.軟珊瑚Xenia屬文獻回顧3
三.柳珊瑚Junceella屬文獻回顧31
四.研究目的44

貳、材料與方法
一.實驗流程45
二. Xenia umbellata Lamarck樣品採集、分類地位46
三. Xenia umbellata Lamarck萃取與分離流程47
四. Junceella juncea Pallas樣品採集、分類地位50
五. Junceella juncea Pallas萃取與分離流程51
六. Junceella fragilis Ridley樣品採集、分類地位53
七. Junceella fragilis Ridley萃取與分離流程54
八.結構鑑定57

參、實驗結果
一.軟珊瑚Xenia umbellata Lamarck所含化合物結構59
二.Xenibelatol A (1)結構解析60
三.Xenibelatol B (2)結構解析70
四.7,8-Oxido-isoxeniolide (3)結構解析80
五.9-Hydroxyxeniolide-F (4)結構解析83
六.Xenitorin A (5)結構解析86
七.柳珊瑚Junceella juncea Pallas所含化合物結構89
八. Juncenolide H (6)結構解析90
九.柳珊瑚Junceella fragilis Ridley所含化合物結構101
十.Flajunolide A (7)結構解析102
十一.Flajunolide B (8)結構解析112
十二.Flajunolide C (9)結構解析122
十三.Flajunolide D (10)結構解析132
十四.Junceellolide E (11)結構解析142
十五.Umbraculolide A (12)結構解析145
十六.11α,20α-Epoxy-4-deacetoxyjunceellolide D (13) 結構解析148

肆、討論151

伍、參考文獻154

陸、附錄162

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