全 文 ：　　　　 　　天然产物研究与开发　 　　　　　
　　　　　　　　　　 NATURAL PRODUCT RESEARCH AND DEVELOPMENT 2005　Vol.17　No.4
　
　
　
　
　　Received May 27 , 2005;Accepted June 20 , 2005
　＊Corresponding author　E-mai l:hping1208@hotmai l.com
Triterpene Acids from Toddalia asiatica
HUANG Ping1＊ ,KARAGIANIS Gloria2 ,WEI Shan-xin1 ,WATERMAN Peter G2
(1.Guangxi Institute of Traditional Medical and Pharmaceutical Sciences , Nanning 530022 , China;
2.Centre for Phytochemistry , Southern Cross University , Lismore 2480 , Australia)
Abstract:Four new triterpene acids , 2α, 3α, 19α-trihydroxy-11-oxo-urs-12-en-28-oic acid(1), 2α, 3α, 11α, 19α-tetrahydroxy-urs-
12-en-28-oic acid(2), 2α, 3α-dihydroxy-19-oxo-18 , 19-seco-urs-11 , 13(18)-dien-28-oic acid(3)and 2α, 3β , 19α-trihydroxy-
olean-11 , 13(18)-dien-28-olic acid(4)were isolated from the stem of Toddalia asiatica , along with the known compounds eu-
scaphic acid (5), arjunic acid(6), toddaculin , toddalolactone and β-sitosterol.Their structures were elucidated on the basis of
spectral evidence.
Key words:Toddalia asiatica ;Rutaceae;triterpene acid
飞龙掌血中三萜酸成分研究
黄　平1＊ ,Karagianis Gloria2 ,韦善新1 ,Waterman Peter G2
(1.广西中医药研究所 , 南宁 530022;2.澳大利亚南十字星大学植物化学研究中心 , Lisomre 2480)
摘　要:从芸香科植物飞龙掌血中提取分离出 4 个新三萜酸 , 经波谱数据分析 ,分别鉴定为 2α, 3α, 19α-trihydroxy-
11-oxo-urs-12-en-28-oic acid(1), 2α, 3α, 11α, 19α-tetrahydroxy-urs-12-en-28-oic acid(2), 2α, 3α-dihydroxy-19-oxo-18 , 19-sec-
o-urs-11 , 13(18)-diene-28-oic acid(3)和 2α, 3β , 19α-trihydroxy-olean-11 , 13(18)-dien-28-oic acid(4)。还分离鉴定出已
知成分野鸭春酸(5)、arjunic acid(6)、飞龙掌血素 、勒钩内脂和 β-谷甾醇。
关键词:飞龙掌血;芸香科;三萜酸
中图分类号:R284.1;R284.2
Introduction
Toddalia asiatica(L.)Lam.(Rutaceae)is mainly dis-
tributed in Asia and Africa.Its roots and root bark are
used in folk medicine to relieve pain and stasis as well as
for haemostatic.The chemical constituents of this plant
have been extensively studied and nearly 40 compounds
have been isolated , including coumarins , alkaloids , a cy-
clohexylamine and a triterpenoid[ 1-5] .We now report the
isolation and structure elucidation of four new 2 , 3-dihy-
droxy triterpene acids and two known 2 ,3-dihydroxy triter-
pene acids , which were found in the Toddalia genus for
the first time.
Result and Discussion
After isolation and purification on semi-preparative HPLC ,
six triterpenes were obtained from the EtOAc soluble frac-
tion of the EtOH extract of T.asiatica.Thirty signals were
Fig.1　Compounds isolated from Toddalia astiatica
observed in each of the 13C NMR spectrum , including one
carbonyl signal at δC 178.3 ～ 181.1.In addition , com-
pounds 1 ～ 3 and 5 exhibited an intensive peak in IR
spectrum at about 1700 cm
-1
for carbonyl group and seven
404
methyl signals in 1H NMR spectrum , of which one methyl
group gave a doublet signal.These initial spectral data
suggested that 1 ～ 3 and 5 possess ursolic acid-type skele-
ton.Compounds 4 and 6 may be oleanolic acid-type triter-
penes in view of their seven tertiary methyl groups in
1
H
NMR spectrum.The assignments of 1H and 13C NMR data
of 1 ～ 6 were based on 1H-1H COSY , NOESY , HSQC
and HMBC experiments.
Compound 1 was obtained as white amorphous powder.
The HR-EIMS showed a peak at m/z 502.3280 , suggest-
ing a molecular formula of C30H46O6.The UV and IR
spectra of 1 indicated the presence ofα,β-unsaturated ke-
tone.This conclusion was further confirmed by 1H NMR
signal at δH 6.16(H-12 , s)and 13C NMR signals at δC
133.5(C-12), 165.9 (C-13)and 200.7(C-11).Two
vicinal oxygenated methines were concluded in view of the
1H NMR signals at δH 4.45(C-2)and δH 3.80(C-3).
The NOE correlations between H-2 and H-3 and H-25
(δH 1.38)in NOESY experiments suggested 2β , 3β-H.
Moreover ,H-18 of 1 displayed a singlet proton at δH 3.13
in the
1
H NMR spectrum , indicating the presence of 19-
OH.The NOESY correlations of H-18(δH 3.13)with H-
20(δH 1.42)and H-29(δH 1.35)suggested 19α-OH and
20α-CH3.Consequently , the structure of 1 was established
as 2α, 3α,19α-trihydroxy-11-oxo-urs-12-en-28-oic acid.
Fig.2　Significant HMBC correlations for compounds 1 , 3 and 4
Fig.3　Significant NOESY correlations for compounds 1 , 3 and 4
The MS spectrum of compound 2 showed significant ion
peaks at m/ z 505 [ M+H] + , 487 [M +H -H2O ] + ,
469 [M+H-2H2O] + , 451[M +H-3H2O] + and 442
[M +H -COOH -H2O ] + , indicating that 2 possesses
one more hydroxyl group than euscaphic acid (5).The
similar
13
C NMR data of 2 and 7a
[ 6]
suggested 2 could be
an isomer of 11-hydroxyltomentic acid(7).The difference
were showed on coupling constant in which H-3(δH
3.75)of 2 exhibited small coupling(J =3.9Hz)but H-
3 of 7a displayed large coupling (J =9.3 Hz)in 1H
NMR spectrum.The NOESY correlations between H-2
(δH 4.31)/H-3(δH 3.75)and H-25 (δH 1.16)sug-
gested 2β , 3β-H.Thus , compound 2 was identified as 2α,
3α,11α,19α-tetrahydroxy-urs-12-en-28-oic acid.
The molecular formula of 3 was assigned as C30H46O5 by
the molecular ion peak at m/z 486.3359 in HR-EIMS.
A characteristic UV absorption band at λmax 242(log ε:
4.26)suggested the presence of a conjugated diene.The
similar 13C NMR data of 3 and those of methyl swihoeate
(8a)[ 7] indicated that 3 could be an isomer of swihoeic
acid(8).Theα-orientation of 2-OH and 3-OH was deter-
mined from the
1
H NMR signal for H-3(δH 3.80 ,d , J =
2.4 Hz) as well as NOESY correlations of H-2 (δH
4.38)and H-3 with H-25 (δH 0.99).Therefore ,3 was
determined as 2α, 3α-dihydroxy-19-oxo-18 , 19-seco-urs-
11 ,13(18)-dien-28-oic acid.The compounds with 18 ,
19-seco-ursane structure are rarely found in nature since
some 3β-hydroxyl-19-oxo-18 , 19-seco-urs-11 , 13(18)-di-
ene-28-oic acid derivatives were isolated from Ilex crena-
ta [ 8 ,9] .
The molecular formula of compound 4 was established as
C30H46O5 by the APCI-MS and HSQC data.The ion peaks
inMS spectrum at m/z 469 [M+H-H2O] + , 451[M
+H-2H2O] + and 433[ M +H -3H2O ] + , 423[M -
HCOOH-H2O] + indicated the presence of three hydrox-
yl groups and one carbonyl in the molecule.Strong UV
4052005　Vol.17　No.4 黄　平等:飞龙掌血中三萜酸成分研究 　
absorptions at λmax 245(sh), 253(logε:4.06)and 261
(sh)nm were characteristics of a conjugated diene[ 10] ,
suggesting that 4 possessed a similar skeleton to that of
2β , 3β-dihydroxy-dean-11 , 13(18)-dien-28-oic acid
(camaldulenic acid , 9)[ 10] .Comparison of the 13C NMR
data with those of 9 , the other hydroxy group could be lo-
cated at C-19(δC 85.3)in 4.This was further confirmed
by HMBC correlation of H-19(δH 4.93)with C-17(δC
44.6), C-21(33.3), C-28(178.2)and C-30(23.5).
The NOESY correlation of H-19 (δH 4.93)with H-30(δH 0.90)suggested 19α-OH.As a result , compound 4
was determined to be 2α,3β ,19α-trihydroxy-olean-11 , 13
(18)-dien-28-oic acid.
The molecular formula of compound 5 was assigned as C30
H48O5 by the molecular ion peak at m/z 488.3508.
Comparison with the reported data of NMR[ 11 ,12] , com-
pound 5 was determined as euscaphic acid.To our best
knowledge , this is the first report of the euscaphic acid
(5)isolated from the Toddalia genus.
Comparison with the reported data[ 13 , 14] , compound 6 was
determined as arjunic acid.This also is the first report of
arjunic acid (6)isolated from the Toddalia genus.
Experimental
General
Column chromatography was carried out on silica gel(200
～ 300 mesh , Qingdao Haiyang Chemical Inc., China).
Semi-preparative HPLC was performed on a Hewlett
Packard 1100 series HPLC using a Zorbax 250 mm×10
mm ,5 μm C-18 semi-preparative column.Purity was de-
termined using an Agilent 125 mm×4 mm ,5μm analyti-
cal column.IR spectra were obtained on a Bruker Vector
33 FT-IR spectrophotometer(KBr disks).UV spectra were
recorded on a Hewlett Packard 8453 UV-visible spec-
trophotometer.NMR data were obtained on a Bruker A-
vance DRX-500 spectrometer(1H:500 MHz;13 C:125
MHz).Mass spectra were obtained using a Hewlett
Packard Agilent 1100 series LC/MSD in APCI mode and
on a Finnigan MAT 95 spectrometer in EI mode.
Plant material
The stem of Toddalia asiatica were collected from Long-
an County ,Guangxi ,China , in July 1990 and identified by
Professor Luo Jinyu.A voucher specimen(No.7324)is de-
posited in the Herbarium of Guangxi Institute of Tradition-
al and Pharmaceutical Sciences.
Extraction and isolation
The dried stems(15 kg)of T .asiatica were extracted with
95%EtOH(3×45 L , reflux).After removal of the solvent
by evaporation in vacuo , the residue(500 g)was mixed
with silica gel and dried in air , then extracted in a Soxhlet
apparatus by EtOAc.The EtOAc extract(48 g)was sub-
jected to column chromatography on a silica gel column
and gradient eluted with petroleum ether(60°～ 90°)and
EtOAc respectively.Toddaculin(21 mg), toddalolactone
(25 mg), β-sitosterol (22 mg)and a mixture of trite-
penoids(86 mg)were obtained.The mixture was further
separated on RP-18 semi-preparative HPLC using 50%～
95%MeOH-H2O solvent system to give compound 1(2
mg), 2(3 mg), 3(2 mg), 4(2 mg), 5(9 mg)and 6(3
mg).
2α, 3α, 19α-Trihydroxy-11-oxo-urs-12-en-28-oic acid
(1)
White amorphous powder:UV(MeOH)λmax(log ε)nm:255
(2.84);IR(KBr)υmax cm-1:3435(br),2933 ,2874 ,1694 ,
1649 , 1458 , 1387 , 1042;HR-EIMS m/ z:502.3280
([M] + , calcd for C30H46O6 , 502.3282).APCI-MS , m/ z
(rel.int.):503([ M +H] + , 100), 485([ M +H -
H2O] + ,36),457([ M+H -COOH] + , 6)and 439([ M
+H-COOH-H2O] + ,9).1H and 13C NMR data:Table
1 and 2.
2α, 3α, 11α, 19α-Tetrahydroxy-urs-12-en-28-oic acid
(2)
White amorphous powder:UV(MeOH)λmax(log ε)nm:204
(3.61),251(2.45);IR(KBr)υmax cm-1:3422(br),2938 ,
2874 , 1692 , 1646 , 1458 , 1388 , 1042;APCI-MS , m/ z
(rel.int.):505([M+H] + ,9),503([M-H] + ,100),
487([M+H -H2O ] + , 33), 469([ M +H-2H2O] + ,
61),451([ M+H-3H2O ] + , 14), 441([ M-COOH-
H2O] + ,79),423(39), 405(28),205(28);1H and 13C
NMR data:Table 1 and 2.
2α, 3α-Dihydroxy-19-oxo-18 , 19-seco-urs-11 , 13(18)-
dien-28-oic acid(3)
White amorphous powder:UV(MeOH)λmax(log ε)nm:242
(4.26);IR(KBr)υmax cm-1:3426(br),2938 ,2871 ,1704 ,
1662 , 1456 , 1386 , 1042;HR-EIMS m/z 486.3359
([M] + , calcd for C30H46O5 , 486.3333).APCI-MS , m/ z
(rel.int.):487 ([ M +H] + , 27), 469 ([ M +H -
H2O] + ,32), 451 ([M +H -2H2O] + , 24), 441 ([M-
COOH] + ,100),423(37), 405(11), 283(10), 205(4);
1H and 13C NMR:Table 1 and 2.
2α, 3β , 19α-Trihydroxy-olean-11 , 13(18)-dien-28-oic
acid(4)
White amorphous powder:UV(MeOH)υmax(logε)nm:245
(sh), 253(4.06), 261(sh);IR(KBr)υmax cm-1:3442(br),2936 ,2867 ,1778 ,1458 ,1388 , 1049;APCI-MS , m/
z(rel.int.):469([M+H-H2O] + , 100), 451([M+H
-2H2O] + ,49), 433([M+H-3H2O] + , 23), 423([M
-HCOOH-H2O] + , 22), 405(27);1H and 13C NMR
data:Table 1 and 2.
406 天然产物研究与开发　　　　　　　　　　　　　 　　　2005　Vol.17　No.4
Table 1　13CNMR data of compounds 1 ～ 7a[ 6](pyridine-d5), 8a[ 7](CDCl3)and 9[ 10](CD3OD)
Position 1 2 3 4 5 6 7a 8a 9
1 43.7 44.3 43.0 48.0 43.3 47.9 48.9 46.0 47.7
2 66.2 66.8 66.3 68.9 66.5 69.0 68.9 68.9 69.5
3 79.4 79.7 79.8 84.2 79.7 84.3 83.7 83.9 84.5
4 39.3 39.1 39.3 40.3 39.2 40.3 40.0 39.3 38.9
5 48.7 49.1 48.7 55.7 49.1 56.5 56.0 55.0 56.7
6 18.0 19.1 18.6 19.0 19.0 19.4 19.2 18.1 18.6
7 34.1 34.3 32.9 33.7 33.9 33.7 33.8 32.0 34.7
8 46.8 44.7 41.6 41.3 41.0 40.5 41.4 40.5 40.5
9 66.3 51.5 55.0 53.6 48.0 48.8 47.4 54.1 55.7
10 39.1 40.0 38.8 38.5 39.1 39.1 39.5 38.0 37.2
11 200.7 81.5 128.0 130.4 24.5 24.7 80.9 127.0 127.0
12 133.5 129.8 130.9 123.8 128.4 123.6 129.7 130.0 126.3
13 165.9 145.1 142.9 135.7 140.3 145.4 144.3 142.8 136.5
14 44.8 42.9 41.9 41.6 42.6 42.6 44.0 41.1 41.8
15 29.6 30.0 26.9 26.3 29.6 29.6 26.0 26.0 26.3
16 26.4 26.7 27.8 25.1 26.8 28.8 25.7 27.0 -
17 48.3 48.4 47.9 44.6 49.7 46.5 48.3 47.1 41.5
18 55 , 5 54.6 129.2 133.7 55.0 45.3 54.0 126.6 135.6
19 73.2 73.2 211.8 85.3 73.7 81.7 72.8 21.2 38.3
20 42.6 42.8 47.8 36.3 42.7 36.1 42.4 47.3 43.2
21 27.0 27.3 28.6 33.3 27.3 29.6 29.1 27.5 31.6
22 38.1 39.0 39.4 35.2 38.9 34.1 38.3 38.2 30.7
23 30.0 30.0 9.7 29.4 29.8 29.7 29.5 16.2 28.9
24 22.7 22.7 22.1 17.6 22.5 18.0 18.9 28.3 17.4
25 18.2 18.6 19.6 20.0 17.0 17.2 18.1 19.1 10.7
26 19.3 19.5 17.2 17.5 17.7 18.0 19.0 16.2 16.8
27 22.1 23.9 20.4 19.6 25.0 25.3 23.6 19.8 24.6
28 180.2 181.1 178.3 178.2 181.0 181.4 178.6 176.0 177.6
29 27.1 27.6 28.4 28.1 27.5 29.2 23.7 28.1 23.7
30 16.9 17.1 16.7 23.5 17.2 25.3 16.8 16.2 32.8
Table 2　1H NMR data of compounds 1～ 6(pyridine-d5)
Position 1 2 3 4 5 6
1
1.98 t(11.8)
3.55 dd ,(12.2 , 3.6)
2.31 t(12.3)
2.70 dd(13.5 ,4.0)
1.86 m
2.21 dd(12.2, 3.6)
1.36 m
2.57 dd(7.4, 4.5)
1.77 dd(11.9)
1.91 t(12.0, 4.3)
1.31 m
2.27 dd(12.5 , 3.4)
2 4.45 dt(11.6) 4.31 dt(11.6) 4.38 dt(10.9) 4.21 ddd(9.4 , 6.7 , 4.3)4.32 dt(10.7 , 3.1) 4.13 ddd(7.0 , 4.3 , 2.3)
3 3.80 s 3.75 d(3.9) 3.80 d(2.4) 3.44 d(9.3) 3.78 d(2.6) 3.41 d(9.3)
4
5 1.68 d(11.8) 1.76 m 1.74 m 1.10 m 1.68 s 1.08 m
6
1.38 m
1.55 m
1.39 m
1.54 m
1.40 m
1.58 m
1.42 m
1.62 m
1.37 m
1.53 m
1.47 m
1.61 m
7
1.38 m
1.78 m
1.37 m
1.67 m 1.40 m 1.41 m
1.42 m
1.71 s
1.42 m
1.60 m
8
9 3.00 s 2.45 d(8.7) 2.30 br s 2.29 s 2.10 m 2.01 t(9.0)
10
11 5.14 m 5.82 d(10.1) 5.94 dd(10.2 , 1.6) 2.10 m
2.19 m 2.19 m
12 6.16 s 6.37 d(3.9) 6.18 dd(10.1, 2.7) 6.27 dd(10.2 , 2.9) 5.60 s 5.58 t(3.4)
13
14
15
1.38 m
2.21 m
1.31 m
2.31 m
1.24 m
2.19 m
1.19 m
1.41 m
1.29 m
2.35 dt(13.6 , 4.7)
1.30 m
2.19 m
4072005　Vol.17　No.4 黄　平等:飞龙掌血中三萜酸成分研究 　
16
2.07 m
3.13 br d(13.1)
2.10 m
3.17 m
1.60 m
2.58 br d(13.1)
1.55 m
2.48 m
2.08 m
3.12 dt(13.1 , 4.5)
2.16 m
2.86 m
17
18 3.13 s 3.21 br s 5.86 s 3.06 s 3.66 s
19 4.93 s 3.63 t(5.8, 4.2)
20 1.42 m 1.51 m 2.55 m 1.53 m
21
1.26 m
2.07 m
1.31 m
2.17 m
1.65 m
2.02 m
1.33 m
1.62 m
1.36 dt(12.5)
2.10 m 2.18 m
22
1.98 m
2.19 m
2.10 m
2.17 m
1.73 m
2.02 m
1.58 m
1.78 dd(12.0 , 4.8)
2.08 m
2.19 m
2.06 m
2.22 dd(13.2 , 3.9)
23 1.30 s 1.28 s 1.28 s 1.30 s 1.28 s 1.30 s
24 0.94 s 0.92 s 0.91 s 1.12 s 0.92 s 1.11 s
25 1.38 s 1.16 s 0.99 s 1.07 s 1.01 s 1.05 s
26 1.30 s 1.23 s 0.92 s 0.77 s 1.13 s 1.10 s
27 0.98 s 1.81 s 0.98 s 1.05 s 1.66 s 1.66 s
28
29 1.35 s 1.67 s 2.12 s 1.08 s 1.44 s 1.21 s
30 1.06 d(6.6) 1.10 d(6.6) 1.08 d(6.9) 0.90 s 1.13 d(5.0) 1.14 s
19-OH 5.59 s 5.14 s
Euscaphic acid(5)
White amorphous powder:UV(MeOH)λmax(logε)nm:209
(3.87);IR(KBr)λmax cm-1:3445(br),2936 ,2871 ,1688 ,1459 ,
1387 ,1039;HR-EIMS m/z 488.3508([M] + , calcd for C30
H48O5 , 488.3498);APCI-MS , m/z(rel.int.):489([M +
H] + ,6), 471([ M+H -H2O ] + , 69), 453([M +H -
2H2O] + ,62), 435([M +H -3H2O] + , 25), 425(49),
407(100);1H and 13C NMR data:Table 1 and 2.
Arjunic acid(6)
White amorphous powder:UV(MeOH)λmax(logε)nm:204
(3.68);IR(KBr)υmax cm-1:3427(br),2939 ,2874 , 1695 ,
1459 , 1386 , 1047;The APCI-MS , m/z(rel.int.):471
([M+H-H2O] + ,20), 453([M+H-2H2O] + , 100),
435([M+H -3H2O] + ,7), 425(7), 407(53);1H and
13C NMR data:Table 1 and 2.
Acknowlezdgments　The authors are grateful to Mr.Don
Brushett for assisting in LC-MS analysis and preparative
HPLC.
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408 天然产物研究与开发　　　　　　　　　　　　　 　　　2005　Vol.17　No.4