全 文 ：波 谱 学 杂 志第 23卷第 4期
2006年 12月　 Chinese Journal of M agnetic Resonance
Vo l. 23 No. 4
　Dec. 2006
Article:1000-4556(2006)04-0451-06
Structure Elucidation of Taraxerone Isolated from
Mangrove Excoecaria Agallocha
L I X iang1 , 2* , LI Min-y i 3 , Z HENGY i-nan1 , LIN Wen-han2
(1. Pharmaceutical Col lege , Ji lin Agricul tu ral Universi ty , Changchun 130118 , China;
2. Nation al Research Lab oratory of Natural and Biomimetic Drugs , Peking University , Bei jing 100083 , Chin a;
3. Guangdong Key Laboratory of Marine Drugs , Guan gzhou 510000 , China)
Abstract:Chemica l screening method was used to isolate tarax erone from mang ro ve E xcoecaria
agal locha. The st ruc ture o f tara xerone iso la ted was determined by NM R and EI-MS methods.
The bio-activities of the compound w ere also evaluated and repor ted.
Key word:ta raxe rone , mang rove , E xcoecaria agallocha , structure elucidation
CLC number:O641　　Document code:A
Introduction
Due to the special living environment o f mang rove , we focus on the chemist ry of
substances f rom Excoecaria agal locha (family:Euphorbiaceae). Excoecaria agal locha
i s well-know n as the plant w hich can pro vide diterpenoids w ith anti-tumor bio activiy
(Erickson et al. 1995)[ 2] and anit-HIV pho rbo l este r (Karalai et al. )[ 3] . A t ri terpenoid-
ta rax erone has been obtained from the hexane ex tract o f the roo t. We now repo rt the
st ructure elucidation and stereo chemist ry resolved by NOESY experiment.
Received date:Mar. 02 , 2006;Revised date:Ju n. 15 , 2006
Foundation i tem:Supp orted by the Nat ional High-Tech Project “ 863” (2001AA624030 , 2002AA217081)and th e Na-
ti onal Natu ral S cien ce Foundation of China (30171106 , 40176038).
Biography:Xiang Li(1976-), Male , Birth Place:Jilin Non gan , Deg ree:PHD , Associate Professor , M ajor:C hemist ry
of Natural Produ ct Research. 　*C orresp onding author:Tel:0+86-13159686878 , E-mail:lixiang@bjm u.
edu. cn.
Fig. 1　St ructu re of compound I
1　Experimental
1. 1　Plant Material
The stem of Excoecaria agal locha has been collected f rom Hai’ Nan Province , Chi-
na , in 2003 , and identi fied by Professo r L in Peng(Xia M en University). The specimen
w as kept in Nat ional Research Laboratory of Natural and Biomimetic Drug s , Peking U-
niversity , Beijing .
1. 2　Isolation
The air-dried material(1 580 g) was ex t racted by 95 % ethenol fo r 3 times. T he
concentrated ext ract w as then dispersed in H 2O and parti tio ned successively w ith Hex-
ane , E tOAc and n-BuOH . The Hexane part w as divided into 6 f ractions chromo tag raph-
ied by sephadex LH-20. Fraction 1(1 869 mg)was repeat ly chromotagraphy by silica gel
(elutiion solvent:Cyclohexane:EtOAc=10∶1) and sephadex LH-20(MeOH) in the
low polarity f raction w e obtained compound I (38 mg).
1. 3　Sample preparation and Apparatus
26. 3 mg compound I was dissolved in 0. 5 mL CDCl3 w ith TMS as an internal refer-
ence , t ransfer red to a 5 mm NMR tube for NMR experiments. All the experiments w ere
performed on a Bruker Avance DRX500 NMR spect rometer equipped wi th a TBI probe ,
a temperature control sy stem and the NMR sof tw are of Xw innmr 3. 5.
1. 4　NMR Experiments
All the experiments w ere performed at room tempe rature , the main paramete rs are
listed in Table 1. NOESY experiment w as done at 293 k w ith a mix ing time of 0. 7 s ,
which w as opt imized wi th the t1 inversion recovery experiment .
1. 5　Bioactivity Experiments
Bioactivity experiments show ed that compound I have no effect on Xanthin-Ox idase
(XOD), 3α-Hydroxy steroid dehydrogenase (3α-HSD) and Horse-radish-perox idase
(HRP) a t a concentration o f 250 μmo l/L .
452 波　　谱　　学　　杂　　志　　　　　　　　　第 23卷　
Table 1　Parameters of all NMR experiments
Experiment SW(kH z) T D S I NS
1H NM R 4. 4 32 k 32 k 8
13C NM R 30. 2 32 k 32 k 2 k
DEPT 30. 2 32 k 32 k 2 k
COSY 4. 5 /4. 5 1 024×256 512×512 4
HMQC 4. 5 /30. 2 1 024×128 512×512 8
HM BC 4. 5 /30. 2 1 024×128 512×512 8
2　Result and Discuss
Compound I was obtained as colo rless needle crystal , the molecular fo rmula w as as-
signed as C30H 48O based on ESI-MS[ M] +:m /z =425. 0163. tw enty-three pro ton sig-
nals w ere found in 1H NMR spectra including 8 methy ls:δ1. 12(s), δ1. 06(s), δ1. 05
(s), δ1. 04(s), δ0. 95(s), δ0. 91(s), δ0. 90(s), δ0. 82(s);9 me thylenes:δ2. 35 ,
2. 55(m , 2H), δ2. 04 , 1. 38(m , 2H), δ1. 90 , 1. 65(m , 2H), δ1. 88 , 1. 35(m , 2H), δ
1. 66 , 1. 48(m , 2H), δ1. 40 , 1. 00(m , 2H), δ1. 32 , 1. 27(m , 2H), 1. 32(m , 2H), δ
1. 30 , 0. 97(m , 2H);5 methines:δ5. 55(dd , 1H), δ1. 60(m , 1H), δ1. 55(m , 1H), δ
1. 48(m , 1H), δ0. 96(m , 1H). 13 C NMR and DEPT spect ra also indicated that there
were 30 carbons in the skeleton therefo re compound I was confirmed as t riterpenoid.
Since there is no oxgenated methine in 1H NMR and together w ith δ217. 5(s) in 13 C
NMR , a carbony l w as assigned in C-3. Acco rding to the 2D NMR (HMQC , COSY and
HMBC)expe riments[ 4] , we assigned all the signal to get the st ructure of compound I:
Table 2　1H-1H COSY data of compound I in CDCl3
H δH 1H-1H COSY H δH 1H-1H COSY
1 1. 88 , 1. 35(m , 2H) 2. 35 19 0. 97 , 1. 30(m , 2H) 0. 96
2 2. 35 , 2. 55(m , 2H) 1. 35 , 1. 88 21 1. 32 , 1. 27(m , 2H) 1. 40 , 1. 00
5 1. 55(m , 1H) 1. 38 , 2. 04 , 1. 32 22 1. 00 , 1. 40(m , 2H) 1. 32 , 1. 27
6 1. 38 , 2. 04(m , 2H) 1. 55 23 1. 06(s , 3H) -
8 1. 48(m , 1H) 1. 48 , 1. 66 24 1. 04(s , 3H) -
10 1. 32(m , 2H) 1. 55 25 1. 05(s , 3H) -
11 1. 48 , 1. 66(m , 2H) 1. 60 26 1. 12(s , 3H) -
12 1. 60(m , 1H) 1. 48 , 1. 66 27 0. 82(s , 3H) -
15 5. 55(dd , 1H) 1. 65 , 1. 90 28 0. 90(s , 3H)
16 1. 65 , 1. 90(m , 2H) 5. 55 29 0. 95(s , 3H) -
18 0. 96(m , 1H) 0. 97 , 1. 30 30 0. 90(s , 3H) -
453
　第 4期　　　　LI Xiang et al:Structure Elucidation o f Tara xerone lsola ted
fr om Mang rove Excoecaria A gallocha
Table 3　HMBC and HMQCdata of compound I in CDCl3
C δC Dept HMBC HMQC
1 38. 4 CH2 H 2 , H-10 , H 23→C1 1. 88 , 1. 35
2 34. 1 CH2 H 1 , H 10 , H-24→C2 2. 35 , 2. 55
3 217. 5 C H 1 , H-24 , H-25, H 10→C3 -
4 47. 5 C H 2 , H 10→C4 -
5 19. 9 CH2 H10→C5 1. 55
6 40. 7 CH2 H10→C6 1. 38 , 2. 04
7 38. 9 C H 5 , H15 , H26→C7 -
8 48. 7 CH H10 , H23 , H 26→C8 1. 48
9 37. 7 C H2 , H5 , H 23→C 9 -
10 55. 8 CH H1 , H6 , H 8→C 10 1. 32
11 17. 5 CH2 H8→C11 1. 48 , 1. 66
12 33. 6 CH2 H8 , H15 , H 28→C 12 1. 60 , 1. 60
13 35. 8 C H 11 , H 15 , H18 , H19 , H 28→C13 -
14 158. 5 C H6 , H 16 , H 26 , H28→C14 -
15 117. 5 CH H 12 , H26 , H28→C15 5. 55
16 37. 7 CH2 H 15 , H22 , H27→C16 1. 65 , 1. 90
17 29. 9 C H 19 , H21 , H27→C17 -
18 48. 8 CH H 22 , H 28→C18 0. 96
19 36. 7 CH2 H 21 , H29 , H30→C19 0. 97 , 1. 30
20 28. 8 C H 18 , H22 , H30→C20 -
21 33. 1 CH2 H 19 , H 30→C21 1. 27 , 1. 32
22 35. 1 CH2 H 18 , H 27→C22 1. 00 , 1. 40
23 14. 8 CH3 H 1 , H8 , H 10→C23 1. 06
24 26. 1 CH3 H 10 , H 25→C24 1. 04
25 21. 5 CH3 H 10 , H 24→C25 1. 05
26 25. 6 CH3 H 6 , H8 , H 15→C26 1. 12
27 29. 9 CH3 H 15 , H16 , H22→C27 0. 82
28 29. 8 CH3 H12 , H 15 , H 18 , H19→C28 0. 90
29 21. 3 CH3 H 19 , H 30→C29 0. 90
30 33. 4 CH3 H 19 , H21 , H29→C30 0. 95
454 波　　谱　　学　　杂　　志　　　　　　　　　第 23卷　
Fig. 2　Main COSY and HMBC of compound I
The stereochemist ry w as so lved mainly by NOESY experiment:
Fig. 3　Key NOE of compound I
References:
[ 1] 　Grabley S , Thiericke R. Drug Discovery f rom Nature[ M] . S pringer Verlag Press:Berlin , 1999. 124.
[ 2] 　Konishi T , Konoshim a T , Maoka T , et a l. Novel di terpenes , excoecarins M and N from the resin ou s w ood of
E xcoecaria agallocha [ J] . Tet rah edron Lett , 2000 , 41:3 419 - 3 422.
[ 3] 　Anjan eyulu A S R , Rao V L. Seco diterpenoids f rom Excoecaria agal locha L[ J] . Phy toch emist ry , 2003 , 62:585
- 589.
[ 4] 　Jiang Gao-xi(蒋高喜) , Li Qin(李勤), Liu Xue-hui(刘雪辉), et al . S t ru cture Elucidat ion for Some Dru gs Using
NM R Technics(一些药物分子的核磁共振应用研究)[ J] . Chinese J Mag n Reson(波谱学杂志), 2003 , 20(4):
393 - 401.
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　第 4期　　　　LI Xiang et al:Structure Elucidation o f Tara xerone lsola ted
fr om Mang rove Excoecaria A gallocha
红树植物海漆中 Taraxerone化合物的结构解析
李　想1 , 2* , 李敏一3 , 郑毅男1 , 林文翰2
(1.吉林农业大学中药材学院 ,吉林 长春 130118;
2.北京大学 天然药物与仿生药物国家重点实验室 , 北京 100083;
3.中国科学院南海海洋研究所 ,广东 广州 510000)
摘　要:应用葡聚糖凝胶 LH-20 , 硅胶柱层析等手段 , 从红树植物海漆 Excoecaria
agal locha 的低极性部位中分离纯化了 1个三萜类化合物 , 结合多种波谱方法(ESI-MS ,
1D NMR , 2D NMR , UV), 确定它的结构为 Taraxerone. 本文将报道该化合物的分离纯
化及波谱解析.
关键词:红树植物;海漆;Taraxerone;结构解析
基金项目:国家高技术计划“ 863”资助项目(2001AA624303, 2002AA217081)和国家自然科学基金资助项目
(30171106 , 40176038).
*通讯联系人:李想 , 电话:+86-13159686878 , E-mail:lixiang@b jmu. edu . cn.
456 波　　谱　　学　　杂　　志　　　　　　　　　第 23卷