Three new lupane-type triterpenes from Ceriops tagal

Article abstract of DOI:10.1080/10286020.2010.485566

Three new lupane-type triterpenes, 3α-O-trans-feruloylbetulinic acid (1), 3α-O-trans-coumaroylbetulinic acid (2) and 3β-O-cis- feruloylbetulin (3), together with 10 known triterpenes (4-13), were isolated from the aerial parts of the mangrove plant Ceriop

Full text of DOI:10.1080/10286020.2010.485566

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Three new lupane-type triterpenes
from Ceriops tagal
a b
a
a
Xia-Chang Wang
, Xiao-Wei Ouyang & Li-Hong Hu
a
Shanghai Institute of Materia Medica, Chinese Academy
of Sciences, Shanghai Research Center for Modernization of
Traditional Chinese Medicine , Shanghai, 201203, China
b
Hainan Provincial Key Laboratory of Drug Quality Research ,
Hainan Provincial Institute For Drug Control , Haikou, 570216,
China
Published online: 13 Jul 2010.
To cite this article: Xia-Chang Wang , Xiao-Wei Ouyang & Li-Hong Hu (2010) Three new lupane-type
triterpenes from Ceriops tagal , Journal of Asian Natural Products Research, 12:7, 576-581, DOI:
10.1080/10286020.2010.485566
To link to this article: http://dx.doi.org/10.1080/10286020.2010.485566
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Journal of Asian Natural Products Research
Vol. 12, No. 7, July 2010, 576–581
ORIGINAL ARTICLE
Three new lupane-type triterpenes from Ceriops tagal
ab†
Xia-Chang Wang , Xiao-Wei Ouyang and Li-Hong Hu *
a†
a
a
Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai Research Center for
b
Modernization of Traditional Chinese Medicine, Shanghai 201203, China; Hainan Provincial Key
Laboratory of Drug Quality Research, Hainan Provincial Institute For Drug Control,
Haikou 570216, China
(
Received 25 January 2010; final version received 11 April 2010)
Three new lupane-type triterpenes, 3a-O-trans-feruloylbetulinic acid (1), 3a-O-trans-
coumaroylbetulinic acid (2) and 3b-O-cis-feruloylbetulin (3), together with 10 known
triterpenes (4–13), were isolated from the aerial parts of the mangrove plant Ceriops
tagal. The structures of the three new compounds were established by means of
spectroscopic data analyses and chemical methods.
Keywords: Ceriops tagal; triterpene; 3a-O-trans-feruloylbetulinic acid; 3a-O-trans-
coumaroylbetulinic acid; 3b-O-cis-feruloylbetulin
1
.
Introduction
trans-coumaroylbetulin (5) [7,8], 3b-O-
trans-feruloylbetulin (6) [9], 3b-O-trans-
coumaroylbetulinic acid (7) [10], 3b-O-
cis-coumaroylbetulinic acid (8) [10],
lupeol (9) [11,12], 3-epi-betulinic acid
Ceriops tagal (Perr.) C. B. Rob (Rhizo-
phoraceae) is an important mangrove plant
both in ecology and economy. In China, it
is distributed mainly on the southern
coastal zone [1]. Previous chemical studies
on C. tagal have resulted in the isolation of
several types of triterpenes, diterpenes,
and tetraterpenes [2–6]. In our studies on
the chemical constituents of C. tagal, three
new lupane-type triterpenes, 3a-O-trans-
feruloylbetulinic acid (1), 3a-O-trans-
coumaroylbetulinic acid (2), and 3b-O-
cis-feruloylbetulin (3) were isolated
together with 10 known triterpenes (4–
(
10) [12–15], betulin (11) [12,15,16], 3-
epi-betulin (12) [17,18], 28-hydroxylup-
0(29)-en-3-one (13) [16,19] by compar-
2
ing their spectroscopic data with those
reported in the literatures.
2. Results and discussion
Compound 1 was obtained as white
powder and deduced to be a triterpene
due to a positive Liebermann–Burchard
test. Its molecular formula was determined
as C H O by HR-ESI-MS at m/z
1
3) (Figure 1). The structures of the new
compounds were established by means of
spectroscopic data analyses, including 1D,
4
0
56
6
þ
655.3971 [M þ Na] . The IR spectrum
2
D NMR, and HR-ESI-MS spectra. The
showed characteristic absorptions of OH
2
1
21
known compounds were identified as 3b-
O-cis-coumaroylbetulin (4) [7,8], 3b-O-
(3426 cm ), C ¼ O (1708, 1685 cm ),
2
1
1
13
and C ¼ C (1635 cm ). The H and
C
*
Corresponding author. Email: simmhulh@mail.shcnc.ac.cn
†
The authors contributed equally to this work.
ISSN 1028-6020 print/ISSN 1477-2213 online
q 2010 Taylor & Francis
DOI: 10.1080/10286020.2010.485566
http://www.informaworld.com

Journal of Asian Natural Products Research
577
1
2
3
4
5
6
7
8
9
R = α-O-trans-feruloyl,
R2 = COOH
R2 = COOH
1
2
9
R = α-O-trans-coumaroyl,
3
0
1
R = CH OH
2 2
2
0
R1 = β-O-cis-feruloyl,
1
9
21
22
R = β-O-cis-coumaroyl,
R = CH OH
2 2
1
12
H
1
8
R = β-O-trans-coumaroyl,
R = CH OH
2 2
11
1
28
25
26
R = CH OH
2 2
1
3
R = β-O-trans-feruloyl,
1
H
17
R2
1
9
14
7
R = β-O-trans-coumaroyl,
R = COOH
2
2
3
1
1
6
10
8
15
R = β-O-cis-coumaroyl,
R = COOH
1
2
H
5
2
4
R = β-OH,
R = CH
2 3
7
1
R1
6
H
10
R = α-OH,
1
R = COOH
2
24
23
11 R = β-OH,
R = CH OH
2 2
1
1
2
3
R = α-OH,
R = CH OH
2 2
1
1
R = ketone,
R = CH OH
2 2
1
5'
6'
5' 6'
4'
1' 7'
4'
1' 7'
HO
O
HO
trans-feruloyl =
cis-feruloyl =
2
'
8'
9'
3'
2'
8' 9'
3'
CH O
CH O
O
3
3
5'
6'
5' 6'
4'
1' 7'
8' 9'
4'
1' 7'
HO
O
HO
trans-coumaroyl =
cis-coumaroyl =
8'
2'
3'
2'
3'
O
9'
Figure 1. Structures of compounds 1–13.
1
Table 1. H NMR spectral data for compounds 1–3 (300 MHz, CDCl
3
, d in ppm).
Position
1
2
3
H-3
H-19
4.74 (m)
3.01 (m)
0.88 (s)
0.90 (s)
0.88 (s)
0.96 (s)
1.06 (s)
4.75 (m)
3.03 (m)
0.88 (s)
0.91 (s)
0.88 (s)
0.97 (s)
1.07 (s)
4.53 (dd, J ¼ 11.1, 6.0 Hz)
2.37 (m)
0.89 (s)
0.87 (s)
0.85 (s)
0.98 (s)
1.05 (s)
3.33 (d, J ¼ 10.5 Hz)
3.79 (d, J ¼ 10.5 Hz)
4.68 (s)
Me-23
Me-24
Me-25
Me-26
Me-27
H-28a
H-28b
H-29a
H-29b
Me-30
–
–
–
–
4.74 (br s)
4.60 (br s)
1.70 (s)
7.03 (d, J ¼ 1.6 Hz)
4.75 (br s)
4.60 (br s)
1.70 (s)
7.42 (d, J ¼ 8.1 Hz)
6.85 (d, J ¼ 8.1 Hz)
6.85 (d, J ¼ 8.1 Hz)
7.42 (d, J ¼ 8.1 Hz)
7.62 (d, J ¼ 16.2 Hz)
6.35 (d, J ¼ 16.2 Hz)
–
4.58 (s)
1.68 (s)
0
H-2
7.62 (d, J ¼ 1.5 Hz)
0
H-3
–
–
0
H-5
6.92 (d, J ¼ 8.1 Hz)
7.10 (dd, J ¼ 1.6, 8.1 Hz)
7.61 (d, J ¼ 15.6 Hz)
6.33 (d, J ¼ 15.6 Hz)
3.94 (s)
6.87 (d, J ¼ 8.1 Hz)
7.10 (dd, J ¼ 1.5, 8.1 Hz)
6.77 (d, J ¼ 12.3 Hz)
5.81 (d, J ¼ 12.3 Hz)
3.81 (s)
0
H-6
0
H-7
0
MeO-3
H-8
0

5
78
X.-C. Wang et al.
1
3
Table 2.
Position
C NMR spectral data for compounds 1–3, 10, and 11 (100 MHz, CDCl3).
1
2
3
10
11
1
2
3
4
5
6
7
8
9
34.1
22.9
78.3
37.2
49.2
18.1
33.9
40.8
50.4
36.9
20.7
25.5
38.3
42.5
29.7
32.2
56.3
46.9
50.4
150.4
30.5
37.1
27.9
21.7
16.1
16.1
14.9
180.9
109.6
19.4
127.1
109.5
146.7
147.8
114.7
122.9
144.4
116.3
166.9
56.1
34.2
23.2
78.7
37.1
49.5
18.3
34.4
41.1
50.7
37.5
20.9
25.7
38.6
42.7
30.8
32.4
56.6
47.1
50.6
150.6
30.0
37.3
28.2
22.0
16.2
16.3
15.1
182.4
110.0
19.6
127.4
130.2
116.1
158.1
116.1
130.2
144.5
116.4
167.6
–
38.6
23.9
80.9
38.1
55.6
18.4
34.3
41.1
50.5
37.3
21.1
25.4
37.5
42.9
27.2
29.4
47.9
48.9
48.1
150.7
29.9
34.2
28.2
16.7
16.4
16.2
14.9
60.7
109.9
19.3
127.5
113.1
144.6
147.2
114.1
125.8
143.8
117.7
166.6
56.2
33.1
25.1
75.8
37.1
48.8
18.1
34.1
40.7
50.1
37.3
20.6
25.4
38.2
42.3
30.4
32.1
56.1
46.9
49.1
150.6
29.5
37.0
28.0
21.9
15.7
15.7
14.4
179.1
109.2
19.0
–
38.9
27.5
79.2
39.0
55.5
18.5
34.4
41.1
50.6
37.3
21.0
25.4
37.5
42.9
27.2
29.3
48.0
48.9
48.0
150.6
29.9
34.1
28.1
15.5
16.3
16.1
14.9
60.7
109.8
19.3
–
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
0
0
0
0
0
0
0
0
0
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
0
MeO-3
–
–
NMR spectral data (Tables 1 and 2)
showed typical NMR signals of lupane-
type triterpene: five methyl singlets at dH
carbons at d 150.4 (C-20) and 109.6 (C-
C
29) for the double bond. By comparison of
the NMR spectral data with those of 3-epi-
betulinic acid (10) [12–15], which was
also isolated from this plant, compound 1
was assigned as a 3-epi-betulinic acid
derivative with an extra ester moiety. The
substituted ester moiety was recognized as
0
0
.88 (Me-23), 0.90 (Me-24), 0.88 (Me-25),
.96 (Me-26), 1.06 (Me-27), one H -19
b
proton signal at dH 3.01 (m), and one
isopropenyl group with the protons at dH
4
.74, 4.60 (both br s) assigned to vinylic
1
methylene (H -29), the proton at d 1.70
2
trans-feruloyl through the H NMR signals
0
H
0
(s) for the attached methyl (Me-30), the
at d 7.03 (H-2 , d, J ¼ 1.6 Hz), 6.92 (H-5 ,
H

Journal of Asian Natural Products Research
579
0
d, J ¼ 8.1 Hz), and 7.10 (H-6 , dd, J ¼ 1.6,
structure of 2 was assigned as 3a-O-trans-
coumaroylbetulinic acid.
8
1
.1 Hz), which was characteristic for a
,3,4-trisubstituted benzene ring, coupled
Compound 3 was obtained as white
powder and the molecular formula was
0
with signals at dH 7.61 (H-7 , d,
0
J ¼ 15.6 Hz) and 6.33 (H-8 , d,
determined as C40
H
58
O
5
from the HR-ESI-
þ
J ¼ 15.6 Hz) for the double bond. The
MS at m/z 641.4186 [M þ Na] . A
0
comparison of the NMR spectral data
(Tables 1 and 2) of 3 with those of 1 and 2
attachment of the methoxyl group to C-3
was evident by the HMBC correlation
0
0
revealed the presence of a lupane-type
triterpene and an aromatic ester moiety.
The triterpene moiety of 3 was identified
as betulin through the resembled NMR
spectral data (Table 2) with those of
betulin and an alkaline hydrolysis of 3
between MeO-3 at d 3.94 and C-3 at d
H
C
0
1
46.7. A strong HMBC correlation of C-9
dC 166.9) with H-3 (dH 4.74, m)
(
determined the feruloyl residue to be
located at C-3. Based on 2D NMR spectral
data, compound 1 was characterized as 3a-
O-trans-feruloylbetulinic acid. The 3a-
configuration was deduced from the
chemical shift of H-3 at dH 4.74 (m),
almost identical to that of 3-epi-betulinic
acid (10) [12–15] except for the esterified
effect (Table 2). As an additional confirm-
ing evidence, compound 1 was subjected
to alkaline hydrolysis to yield 3-epi-
betulinic acid (10), according to the same
physical and spectroscopic properties as
that of the authentic sample.
1
yielding betulin (11) [11,14,15]. The H
NMR spectrum showed two hydroxy-
methyl protons at d 3.79, 3.33 (each 1H,
H
d, J ¼ 10.5 Hz, H -28). A cis-feruloyl
2
moiety was established from the presence
of the cis-oriented double bond: dH 6.77
0
(
1H, d, J ¼ 12.3 Hz, H-7 ), 5.81 (1H, d,
0
J ¼ 12.3 Hz, H-8 ), and the 1,3,4-trisub-
0
stituted benzene ring: d 7.62 (H-2 , d,
H
0
J ¼ 1.5 Hz), 6.87 (H-5 , d, J ¼ 8.1 Hz),
0
and 7.10 (H-6 , dd, J ¼ 1.5, 8.1 Hz). From
the above evidence, the structure of 3 was
elucidated as 3b-O-cis-feruloylbetulin.
By comparison of their spectral data
with those reported in the literature, 10
known compounds were identified as 3b-
O-cis-coumaroylbetulin (4), 3b-O-trans-
coumaroylbetulin (5), 3b-O-trans-feru-
loylbetulin (6), 3b-O-trans-coumaroyl-
Compound 2 was obtained as white
powder and has a molecular formula of
C H O according to HR-ESI-MS. The
3
9 54 5
NMR spectral data of 2 closely resembled
those of 1, composed of a lupane-type
triterpene, 3-epi-betulinic acid, and an
aromatic ester moiety (Tables 1 and 2).
The ester moiety of 2 was established to be
betulinic
coumaroylbetulinic acid (8), lupeol (9),
-epi-betulinic acid (10), betulin (11), 3-
epi-betulin (12), and 28-hydroxylup-
acid
(7),
3b-O-cis-
1
trans-coumaroyl according to the H NMR
signals at d 7.42 (2H, d, J ¼ 8.1 Hz) and
H
3
6
a p-substituted benzene ring, together
.85 (2H, d, J ¼ 8.1 Hz), characteristic for
20(29)-en-3-one (13).
0
with the signals at dH 7.62 (H-7 , d,
0
J ¼ 16.2 Hz) and 6.35 (H-8 , d,
3.
Experimental
J ¼ 16.2 Hz) for the conjugated C ¼ C
double bond. The trans-coumaroyl moiety
placed at C-3 resulted from the similar
downfield shifts observed for H-3 and C-3
3.1 General experimental procedures
Optical rotations were measured on a
Perkin-Elmer 341 polarimeter. IR spectra
were measured on a Nicolet FTIR 750
1
with those of compound 1 in the H and
1
C NMR spectra (Tables 1 and 2). On
3
1
13
spectrophotometer. H NMR, C NMR,
DEPT, HSQC, and HMBC spectra were
recorded with Bruker AMX-300/400
instruments. HR-ESI-MS was carried out
alkaline hydrolysis, compound 2 also
afforded 3-epi-betulinic acid (10). There-
fore, based on the above evidence, the

5
80
X.-C. Wang et al.
using Micromass Q-Tof Global mass
spectrometers. ESI-MS was recorded on
a Bruker Esquire 3000 plus spectrometer.
All solvents used were of chemical grade
and purchased from the Shanghai Chemi-
cal Plant (Shanghai, China). MCI Gel
CHP20P (75–150 mm) was purchased
from Mitsubishi Kasei Chemical Indus-
tries (Tokyo, Japan). Silica gel (200–
separated further on an RP-18 column
(70–80% MeCN/H O) to yield com-
2
pounds 1 (8.5 mg), 2 (15 mg), 3 (54 mg),
4 (103 mg), 5 (201 mg), 6 (42 mg), 7
(23 mg), and 8 (56 mg). Fraction II (3.6 g)
was subjected to a silica gel column eluted
with petroleum ether–EtOAc 9:1 to yield
compound 9 (602 mg). Fraction III (7.3 g)
was subjected to a silica gel column eluted
with petroleum ether–EtOAc 8:2 to yield
compound 10 (810 mg). Fraction V (5.3 g)
was subjected to a silica gel column eluted
with petroleum ether–acetone 8:2 to yield
compound 11 (81 mg). Fraction IV (6.5 g)
was subjected to an RP-18 column eluted
3
00 mesh) was purchased from Qingdao
Marine Chemical Ltd (Qingdao, China).
RP-18 (20–45 mm) was purchased from
Fuji Silysia Chemical Ltd (Aichi, Japan).
TLC Silica gel GF-254 Plates were
purchased from Yantai Huiyou Inc.
(Yantai, China).
with 85% MeCN/H O to yield compounds
2
12 (820 mg) and 13 (930 mg).
3
.2 Plant material
3
.3.1 3a-O-trans-Feruloylbetulinic acid
The aerial parts of C. tagal (Perr.) C. B.
Rob were collected in August 2008, from
Wenchang City, Hainan Province, China.
The plant was identified by Pharmacist-in-
charge Chuan-Shan Fu (Hainan Huatuo-
tianya Pharmaceutical Co. Ltd., Haikou,
Hainan, China) and a voucher specimen
(
1)
2
0
White powder, [a ]D ¼ 215 (c ¼ 0.02,
CHCl ); IR (KBr) n : 3426, 2944, 2871,
3
max
1708, 1685, 1635, 1513, 1452, 1261, 1170,
2
1
1
1029 cm ; H NMR spectral data, see
1
Table 1; C NMR spectral data, see
3
þ
(No. 20080804) has been deposited at the
Table 2; ESI-MS m/z: 655.4 [M þ Na] ,
–
631.9 [M–H] ; HR-ESI-MS (positive)
herbarium of Shanghai Research Center
for Modernization of Traditional Chinese
Medicine, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences,
Shanghai, China.
þ
m/z: 655.3971 [M þ Na] (calcd for
C H O Na, 655.3975).
40 56 6
3.3.2 3a-O-trans-Coumaroylbetulinic
acid (2)
3
.3 Extraction and isolation
20
White powder, [a ]D ¼ 212 (c ¼ 0.045,
The aerial parts of C. tagal (10 kg) were
powdered and extracted with 95% ethanol
at room temperature three times. Evapor-
ation of ethanol left a crude extract
CHCl ); IR (KBr) n : 3411, 2946, 2871,
max
3
1710, 1685, 1604, 1513, 1272, 1166, 979,
2
1
1
831 cm
Table 1; C NMR spectral data, see
;
H NMR spectral data, see
1
3
þ
(1.2 kg), which was suspended in H O,
2
Table 2; ESI-MS m/z: 625.5 [M þ Na] ,
–
601.6 [M–H] ; HR-ESI-MS (positive)
then extracted with EtOAc to afford the
EtOAc soluble fraction (272 g). The
EtOAc extract was firstly subjected to a
column of MCI gel eluted with 30%, 70%,
þ
m/z: 625.3863 [M þ Na] (calcd for
C H O Na, 625.3869).
9 54 5
3
and 100% MeOH/H O. Then, 123 g of the
2
3
.3.3 3b-O-cis-Feruloylbetulin (3)
2
MeOH fraction was chromatographed over
a silica gel column (petroleum ether–
acetone, 25:1–1:10), to yield seven frac-
tions I–VII. Fraction VII (5.3 g) was
0
White powder, [a ]D ¼ þ28 (c ¼ 0.065,
CHCl ); IR (KBr) n : 3440, 2942, 2871,
max
3
1702, 1631, 1594, 1515, 1454, 1270, 1172,

Journal of Asian Natural Products Research
581
2
033, 981, 756 cm ; H NMR spectral
1
1
1
data, see Table 1; C NMR spectral data,
see Table 2; ESI-MS m/z: 641.4
[3] Y. Zhang, Y. Lu, L. Mao, P. Proksch, and
W.H. Lin, Org. Lett. 7, 3037 (2005).
1
3
[
4] C. Pakhathirathien, C. Karalai, C. Pongli-
manont, S. Subhadhirasakul, and K.
Chantrapromma, J. Nat. Prod. 68, 1787
þ
–
[
(
(
M þ Na] , 617.7 [M–H] ; HR-ESI-MS
þ
positive) m/z: 641.4186 [M þ Na]
(2005).
[5] J.D. Chen, Y. Qiu, Z.W. Yang, P. Lin, and
Y.M. Lin, Helv. Chim. Acta 91, 2292
calcd for C H O Na, 641.4182).
4
0
58
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.4 Alkaline hydrolysis of 1–3
[
A sample of 1 (2 mg) was added in 5%
KOH–MeOH (5 ml) and the mixture was
heated at 658C for 10 h, the solvent was
evaporated under vacuum, then 10 ml
water was added and mixed. The mixture
was extracted with EtOAc (10 ml £3) and
the EtOAc extract was purified to yield 3-
epi-betulinic acid (10), which was con-
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1
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1
[
firmed by H NMR spectrum and TLC
comparison with an authentic sample.
Compounds 2 and 3 were treated
individually in the same way as described
for 1 to yield 3-epi-betulinic acid (10) and
betulin (11), respectively.
[
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Acknowledgements
This work was financially supported by the
Chinese National Science & Technology Major
Project ‘Key New Drug Creation and Manu-
facturing Program’ (Grants 2009ZX09301-001,
[
[
[
2009ZX09102-022), the Chinese National High-
(
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2006).
Tech R&D Program (Grants 2007AA02Z147),
the National Natural Science Foundation of
China (Grants 90713046, 30772638, 30925040),
and CAS Foundation (Grants KSCX2-YW-
R-179).
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