薄葉嘉賜木 (Casearia membranacea Hance) 為大風子科 (Flacourtiaceae) 嘉賜木屬 (Casearia) 之常綠喬木，採集於台灣北部山區。以生物活性為導向對其甲醇層進行分離純化，共得到六個新的雙萜類化合物，Caseambrins A-F (1-6) 以及一個已知的化合物rel-(2S,5R,6R,8S,9S,10R,18S,19R)-diacetoxy-18,19-epoxy-6-hydroxy-2-
(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (7)。化合物1-6的結構鑑定是利用物理資料 (紅外線光譜、質譜、旋光度) 以及一維、二維核磁共振光譜分析，再加上相關文獻資料比對所建立的。
從薄葉嘉賜木分離得到的化合物其基本骨架為clerodane diterpenes，而化合物1-6 亦具有其相同骨架；主要結構皆為兩個六圓環，在第9位上接了具有六個碳的共軛雙鍵側鏈，以及在C-2位置和C-18上接有兩個酯基官能基。
化合物1在C-18位上接有酯基烷類側鏈，且在C-6、19位上分別有烃基及乙醯基取代，其化學結構為rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18-butanoyloxy-19-acetoxy-18,19-
epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (Caseamembrin A)。化合物2在C-18位上接有OMe 之取代基，化學結構為rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18-methoxy-19-acetoxy-18,19
-epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (Caseamembrin B)。化合物3在C-19位上有乙醯基之取代基，以及在C-6、7位上為OH，鑑定為rel-(2S,5R,6R,7R,8S,9S,10R,18S,19R)
-18-butanoyloxy-19-acetoxy-18,19-epoxy-6,7-dihydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14- triene (Caseamembrin C)。化合物4 其6位上接了OH，而C-7、19位上分別為乙醯基取代，化學結構為rel-(2S,5R,6S,7R,8S,9S,10R,18S,19R)-18-butanoyloxy-19-acetoxy-18,19
-epoxy-6-hydroxy-7-acetoxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14- triene (Caseamembrin D)。化合物5在18、19位上皆為乙醯基取代，6位上則為OH，鑑定為rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18,19-
diacetoxy-18,19-epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (Caseamembrin E)。化合物6 在C-6 位上接了OH，在C-18、19位上則開環取代的是兩個醛基，化學結構為rel-(2S,5R,6R,7R
,8S,9S,10R,18S,19R)-6-hydroxy-2-(2-methylbutanoyloy)cleroda-3,13(16),14-triene-18,19-dicarboxyaldehyde (Caseamembrin F)。
化合物1-6為首次發現新的天然物結構，在細胞毒殺活性方面，對於人類胃癌細胞及人類鼻咽癌細胞，化合物1-6在濃度20mg/ml毒殺活性達到0~1﹪。

Casearia membranacea Hance (Flacourtiaceae) is a tree found in the northern region of Taiwan. Bioassay-directed fractionation of the MeOH-layer has resulted in the isolation of six new clerodane diterpenes, Caseamembrins A-F (1-6) along with a known compound, rel-(2S,5R,6R,
8S,9S,10R,18S,19R)-diacetoxy-18,19-epoxy-6-hydroxy-2-(2-methylbut-
anoyloxy)cleroda-3,13(16),14-triene (7).

The structures of compounds 1-6 were determined by the physical methods such as IR、mass、optical rotation, 1D、2D NMR spectral analysis, and the published reports about the data of related compounds .

The spectral data of 1-6 are in conformity with the basic skeleton of clerodane diterpenes previously isolated from Casearia membranacea Hance.. The basic structures of 1-6 contain two 6-membred ring linked with six carbon diene side chain at C-9 and two ester carbonyl functional groups at C-2 and C-18 respetirely.

Compound 1 had an ester carbonyl at C-2 position, with an acetoxyl and a hydroxyl group at C-19/6 position, the structure of 1 was assigned as rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18-butanoyloxy-19-acetoxy-18,19
-epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (Caseamembrin A). Compound 2 had a methoxyl group at C-18 position, that 2 has the structure of rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18-methoxy
-19-acetoxy-18,19-epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (Caseambrin B). Compound 3 had an acetoxyl at C-19 position, and two hydroxyl group at C-6/7. Compound 3 was assigned the structure of rel-(2S,5R,6R,7R,8S,9S,10R,18S,19R)-18-butanoyloxy-19-
acetoxy-18,19-epoxy-6,7-dihydroxy-2-(2-methylbutanoyloxy)cleroda-3,
13(16),14- triene (Caseamembrin C). Compound 4 had two acetoxyl at C-7/19 and hydroxyl group at C-6, the assignment of its structure as rel-(2S,5R,6S,7R,8S,9S,10R,18S,19R)-18-butanoyloxy-19-acetoxy
-18,19-epoxy-6-hydroxy-7-acetoxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14- triene (Caseamembrin D). Compound 5 had two acetoxyl at C-18/19 position, and a hydroxyl group at C-6 position. 5 was established as rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18,19-diacetoxy-18,19-epoxy-6-
hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (Caseamembrin E). Compound 6 had a hydroxyl group at C-6 position and it was deduced that the C-18/19 acetal ring was opened thus forming the two aldehydic units. The structure of 6 was established as rel-(2S,5R,6R,7R,8S,9S,10R,18S,19R)-6-hydroxy-2-(2-methylbutanoyloy)
cleroda-3,13(16),14-triene-18,19-dicarboxyaldehyde (Caseamembrin F).

It is worthy to mention that this is the first report of the isolation of 1-6 from a natural source. In a preliminary pharmacological aporach (cytotoxicity), compounds 1-6 exhibited moderate cytotoxicity against (NUGC-3) and (HONE-1) cancer cells with IC50 0~1﹪values at 20mg/ml.

目 錄
頁次
壹 緒論
第一章 前言…………………………………………………………1
第二章 過去成分研究相關文獻回顧………………………………3
第三章 研究動機與目的……………………………………………12

貳 材料與方法
第一章 樣品的採集…………………………………………………13
第二章 分離與純化…………………………………………………14
第三章 結構之鑑定…………………………………………………19
第一節 儀器部分
第二節 矽膠與溶劑部分
第四章 衍生物之製備………………………………………………21
第一節 乙醯基化反應 (Acetylation)
第二節 酯化反應 (Esterification)
第五章 生物活性之篩選……………………………………………23

參 結果與討論…………………………………………..…………25
肆 結論…………………………………………………..…………75
伍 參考文獻……………………………………………..…………81

伍 參考文獻
1. http://www.nsfc.gov.cn:8000/nsfc/cen/00/kxb/dq/yxzz/dqhj/3_2.htm
2. http://www.takungpao.com/news/2003-2-24/_IN-107421.htm
3. Oberlies, N. H.; Burgess, J. P.; Navarro, H. A.; Pinos, R. E.; Fairchild, C. R.; Peterson, R. W.; Soejarto, D. D.; Farnsworth, N. R.; Kinghorn, A. D.; Wani, M. C.; Wall, M. E. Structure and Stereochemistry of New Cytotoxic Clerodane Diterpenoids from the Bark of Casearia lucida from the Madagascar Rainforest J. Nat. Prod. 2002, 65(2), 95-99.
4. Prakash, C. V. S.; Hoch, J. M.; Kingston, D. G. I. Novel Bioactive Clerodane Diterpenoids from the Leaves and Twigs of Casearia sylvestris J. Nat. Prod. 2002, 65(2), 100-107.
5. Itokawa, H., Totsuka, N., Morita, H., Takeya, K., Iitaka, Y., Schenkel, E. P., Motidome, M. New Antitumor Principles, Casearins A-F, for Casearia sylvestris Sw. (Flacourtiaceae) Chem. Pharm. Bull. 1990, 38, 3384-3388.
6. Morita, H., Nakayama, M., Kojima, H., Takeya, K., Itokawa, H., Schenkel, E. P., Motidome, M. Structures and Cytotoxic Activity Relationship of Casearins, New Clerodane Diterpenes from Casearia sylvestris Sw. Chem. Pharm. Bull. 1991, 39, 693-697.
7. Carvalho, P. R. F., Furlan M., Young, M. C. M., Kingston, D.G. I., Bolzani, V. S. Acetylated DNA-Damaging Clerodane Diterpenes from Casearia Sylvestris Phytochemistry 1998, 49, 1659-1662.
8. Itokawa, H., Totsuka, N., Takeya, K., Watanabe, K., Obata, E. Antiyumor Principles from Casearia Sylvestris Sw. (Flacourtiaceae), Structure Elucidation of New Clerodane Diterpenes By 2-D NMR Spectroscopy Chem. Pharm. Bull. 1988, 36, 1585-1588.
9. Hunter, M. S., Corley, D. G., Carron, C. P., Rowold, E., Kilpatrick, B. F., Durley, R. C. Four New Clerodane Diterpenes from the Leaves of Casearia guianensus Which Inhibit the Interaction of Leukocyte Function Antigen 1 with Intercellular Adhesion Molecule 1 J. Nat. Prod. 1997, 60, 894-899.
10. Gibbons, S., Gray, A. I., Waterman, P. G., Clerodane Diterpenes from The Bark of Casearia Tremula Phytochemistry 1996, 41, 565-570.
11. Guittet, E., Stoven, V., Lallemand, J. Y. Pitumbin, a Novel Kolavene Acylal from Casearia pitumba Pleumer Tetrahedron 1988, 44, 2901-2893.
12. Beutler, J. A., McCall, K. L. Herbert, K., Herald, D. L., Pettit, G. R., Johnson, T., Shoemaker, R. H., Boyd, M. R. Novel Cytotoxic Diterpenes from Casearia arborea J. Nat. Prod. 2000, 63, 657-661.
13. Khan, M. R., Gray, A. I., Sadler, I. H. Waterman, P. G. Phytochemistry 1990, 29, 3591-3595.
14. Chen, T. B., Wiemer, D. F. J. Nat. Prod. 1991, 54, 1612-1618.
15. Gunasekera, S. P., Sultanbawa, M. U. S. Balasubramaniam, S. Phytochemistry 1977, 16, 788-789.
16.Talapatra, S. K., Ganguly, N. C., Goswami, S., Talapatra, B. J. Nat. Prod. 1983, 46, 401-408.
17.Shaari, K., Waterman, P. G. J. Nat. Prod. 1994, 57, 720-724.
18.Khan, M. R., Gray, A. I. and Waterman, P. G. Rev. Latinoam. Quim. 1989, 20, 75.
19.Gonzalez, A. G., Fraga, B. M., Hernandez, M. G. and Luis, J. G. Phytochemistry. 1973, 12, 1113.
20.Tanaka, R. and Matsunaga, S. Phytochemistry. 1988, 27, 2273.
21. Cross, B. E., Gatt, R. H. B., Hanson, J. R., Curtis, P. J., Grove, J. E. and Morrison, A. J. Chem. Soc. 1963, 1459.