Chemical constituents of Euonymus fortunei

Article abstract of DOI:10.1080/10286020.2015.1030401

A new flavonol glycoside, kaempferol-3-O-β-d-(2-O-E-p-coumaroyl)-glucopyranosyl-7-O-α-l-rhamnopyranoside (1), along with eleven known compounds including five flavonol glycosides (2-6), one phenolic glycoside (7), two megastigmane glycosides (8 and 9), two triterpenoids (10 and 11) and one alditol (12), was isolated from the aerial parts of Euonymus fortunei. Their structures were determined on the basis of spectroscopic analysis and chemical evidence. Compounds 2-4, 7, 8, and 10-12 were evaluated their antimicrobial activities against Ureaplasma urealyticumin vitro, but all tested compounds have no useful activities against Ureaplasma urealyticum.

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Chemical constituents of Euonymus
fortunei
Li-Hua Yanab, Xiao-Qian Liuab, Hui Zhuab, Qing-Rui Xuc, Wei-Ming
Wangc, Shu-Ming Zhangc, Qi-Wei Zhangab, Shan-Shan Zhangab
Zhi-Min Wangab
&
a Institute of Chinese Materia Medica, China Academy of Chinese
Medical Sciences, Beijing 100700, China
b National Engineering Laboratory for Quality Control Technology
of Chinese Herbal Medicines, Beijing 100700, China
c Heilongjiang Academy of Chinese Medical Sciences, Harbin
150036, China
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Published online: 29 Apr 2015.
To cite this article: Li-Hua Yan, Xiao-Qian Liu, Hui Zhu, Qing-Rui Xu, Wei-Ming Wang, Shu-Ming
Zhang, Qi-Wei Zhang, Shan-Shan Zhang & Zhi-Min Wang (2015): Chemical constituents of Euonymus
fortunei, Journal of Asian Natural Products Research, DOI: 10.1080/10286020.2015.1030401
To link to this article: http://dx.doi.org/10.1080/10286020.2015.1030401
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Journal of Asian Natural Products Research, 2015
http://dx.doi.org/10.1080/10286020.2015.1030401
Chemical constituents of Euonymus fortunei
Li-Hua Yanab, Xiao-Qian Liuab, Hui Zhuab, Qing-Rui Xuc, Wei-Ming Wangc,
Shu-Ming Zhangc, Qi-Wei Zhangab, Shan-Shan Zhangab and Zhi-Min Wangab*
aInstitute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700,
China; National Engineering Laboratory for Quality Control Technology of Chinese Herbal
b
c
Medicines, Beijing 100700, China; Heilongjiang Academy of Chinese Medical Sciences, Harbin
150036, China
(Received 11 December 2014; final version received 13 March 2015)
A new flavonol glycoside, kaempferol-3-O-b-D-(2-O-E-p-coumaroyl)-glucopyrano-
syl-7-O-a-L-rhamnopyranoside (1), along with eleven known compounds including
five flavonol glycosides (2–6), one phenolic glycoside (7), two megastigmane
glycosides (8 and 9), two triterpenoids (10 and 11) and one alditol (12), was isolated
from the aerial parts of Euonymus fortunei. Their structures were determined on the
basis of spectroscopic analysis and chemical evidence. Compounds 2–4, 7, 8, and 10–
12 were evaluated their antimicrobial activities against Ureaplasma urealyticum
in vitro, but all tested compounds have no useful activities against Ureaplasma
urealyticum.
Keywords: Celastraceae; Euonymus fortunei; flavonol glycosides; megastigmane
glycosides; Ureaplasma urealyticum
1. Introduction
Ureaplasma urealyticum has been impli-
cated in both genital disease and infertility
in man. Drug tolerance may occur with
continuing use of existing antibiotics, so an
effective antibiotic treatment is still
urgently required [7].
Euonymus fortunei (Turcz.) Hand.-Mazz
(Celastraceae), known as “Fu-Fang-Teng”
in Chinese, is an evergreen shrub with
decumbent stems widely distributed in
China. It has been used in Traditional
Chinese Medicine for the treatment of
rheumatism, metrorrhagia, traumatic
injury, and so on [1]. Known constituents
of E. fortunei include triterpenes, flavo-
noids, lignans, and sesquiterpene pyridine
alkaloids [2–5]. Dihydro-b-agarofuran
sesquiterpenoids are characteristic con-
stituents of the family Celastraceae, and
they have attracted a great deal of interest
because of their cytotoxic, insect antifee-
dant, insecticidal, and anti-HIV activities.
Some species of the family Celastraceae
have been used for cancer, psoriasis,
contraception and as an insecticide [6].
In this study, a phytochemical investi-
gation is reported on a 70% ethanol extract
from the aerial parts of E. fortunei and
focuses on the isolation of higher polarity
compounds. A new flavonol glycoside,
kaempferol-3-O-b-D-(2-O-E-p-coumar-
oyl)-glucopyranosyl-7-O-a-L-rhamnopyra-
noside (1), along with 11 known compounds
(2–12) were isolated and identified
(Figure 1). Compounds 6, 8, and 9 were
obtained from the genus Euonymus for the
first time. The in vitro activities of
compounds 2–4, 7, 8, and 10–12 against
Ureaplasma urealyticum were attemped to
evaluate.
*Corresponding author. Email: zhmw123@163.com
q 2015 Taylor & Francis

2
L.-H. Yan et al.
H
3'
6'
R1
H
OH
5'''
4'
1'''
2'
1'
6'''
HO
4'''
O
OH
O
8
HO
3''' 2'''
O
O
5'
2
7
9
HO
O
HO
OH
O
O
OH
3
6
10
4
5
O
OR2
O
OH
6''
5''
O
H
O
OH
1''
4''
2''''
6''''
3''''
2''
HO
1''''
H
2 R1 = H, R2 = β-
3 R1 = H, R2 = H
4 R1 = H, R2 = α-
D
-Glc
HO
3''
4''''
O
HO
7''''
9''''
L-Rha
5''''
8''''
4
O
5 R1 = H, R2 = CH3COO-α-
L
-Rha
1
6 R1 = OH, R2 = H
HOH2C
OCH3
O
OR2
6
1
9
R1
OCH3
OH
O
3
HO
HO
O
OH
HO
8 R1 = CH2OH, R2 = β-D-Glc; 6S, 9S
9 R1 =CH3, R2 = β-D-Glc; 6S, 9R
7
CH2OH
HO
HO
OH
OH
CH2OH
HO
HO
12
10
11
Figure 1. Structures of compounds 1–12.
2. Results and discussion
doublets at dH 6.70 and 6.88, J ¼ 1.8 Hz)
and a 40-hydroxylated pattern for ring B
(AA0BB0 system signals at dH 8.46 and
7.30, each d, J ¼ 8.4 Hz), which indicated
the presence of kaempferol as aglycone.
The 1H NMR spectrum also exhibited two
doublets at dH 8.02 and 6.68 with large
coupling constants (15.6 Hz), which ident-
ified trans olefinic double bond protons,
and p-hydroxyl phenyl ring showing
another AA0BB0 pattern (dH 7.47 and
7.09, each d, J ¼ 8.4 Hz), which suggested
the presence of the p-coumaroyl moiety.
Compound 1 was isolated as pale yellow
amorphous powder. Its molecular formula
was determined as C36H36O17 by HR-ESI-
MS (m/z 763.1866 [M þ Na]þ). The UV
absorption maxima (269, 317 nm) indi-
cated the flavonoid skeleton. The IR
spectrum showed absorption bands for
hydroxyl groups (3364 cm21), chelated
carbonyl (1655 cm21), and ester carbonyl
groups (1702 cm-1). The 1H NMR spectrum
of 1 (Table 1) showed a 5, 7-di-hydroxyl-
ated pattern for ring A (two meta-coupled

Journal of Asian Natural Products Research
3
Table 1. 1H (600 MHz) and 13C NMR (150 MHz) spectral data of compound 1 in C5D5N.
Positions
dH (J in Hz)
dC
HMBC(H-C)
2
3
4
5
6
7
8
157.1
134.3
178.3
156.5
100.1
162.4
94.4
6.70(1H, d, 1.8)
6.88(1H, d, 1.8)
C-8, 10, 4, 7
C-6, 10, 5, 7,
9
10
10
20, 60
300, 50
400
100
2
300
400
500
600
162.1
106.6
121.5
131.7
116.1
161.7
100.0
75.5
76.0
71.5
79.2
62.1
8.46(2H, d, 8.4)
7.30(2H, d, 8.4)
C-2, 40
C-10, 40
6.69(1H, d, 7.8)
C-3, 300, 500
C-90000, 100, 300
C-200, 400
6.04(1H, dd, 7.8, 9.6)
4.52(1H, t, 9.6)
4.28(1H, t, 9.6)
C-300, 500, 600
C-400, 600
4.12(1H, m)
4.42(1H, dd, 12.0, 2.4)
4.24(1H, dd, 12.0, 5.4)
6.18(1H, d, 1.2)
4.67(1H, dd, 3.0, 1.2)
4.61(1H, dd, 9.0, 3.0)
4.35(1H, t, 9.0)
C-400
C-500
1000
99.7
71.4
72.1
73.3
71.2
18.4
125.9
130.4
116.5
161.1
145.3
115.2
166.9
C-7, 5000
2000
C-4000, 3000, 1000
C-4000, 2000
C-3000, 5000
C-4000, 6000
C-4000, 5000
3000
4000
5000
4.25(1H, dd, 9.0, 6.6)
1.62(1H, d, 6.6)
6000
10000
20000, 60000
30000, 50000
40000
7.47(2H, d, 8.4)
7.09(2H, d, 8.4)
C-40000, 70000
C-10000, 40000
70000
80000
90000
5-OH
8.02(1H, d, 15.6)
6.68(1H, d, 15.6)
C-90000, 20000, 60000, 80000
C-10000, 70000, 90000
13.25(1H, br s)
The 1H NMR spectrum also supported the
presence of one glucose and one rhamnose
with the glucose anomeric proton at dH 6.69
(d, J ¼ 7.8 Hz) and the rhamnose H-1 at dH
6.18 (d, J ¼ 1.2 Hz). The 13C NMR
spectrum displayed the corresponding
signals attributable to kaempferol, p-
coumaroyl, and two sugar units. The sugars
obtained by acid hydrolysis of 1 were
identified as D-glucose and L-rhamnose by
GC analysis of their trimethylsilyl-L-
cysteine derivatives of the hydrolysate of
1 and the authentic sugars. The J values of
the anomeric proton signals indicated that
the glycosidic linkage of glucose was b
configuration, and those of rhamnose was a
configuration. The p-coumaroyl subunit
was confirmed by the HMBC correlations
(Figure 2) from H-80000 (dH 6.68) to C-10000
(dC 125.9) and from H-70000 (dH 8.02) to C-
90000 (dC 166.9). In addition, the glycosidic
linkage positions were unambiguously
determined by HMBC correlations from
H-100 (dH 6.69, Glc) to C-3 (dC 134.3) and
from H-1000 (dH 6.18, Rha) to C-7 (dC
162.4), which confirmed that the b-
glucopyranose and a-rhamnopyranose
units were attached to C-3 and C-7 of
kaempferol, respectively. These spectral
data suggested that the structure of 1 was

4
L.-H. Yan et al.
H
OH
1'''
O
HO
1'
O
O
O
HO
OH
O
OH
HO
O
1''
H
H
HO
HO
H
1''''
O
HO
9''''
H
O
Figure 2. Key HMBC correlations of compound 1.
similar to that of kaempferol-3-O-b-D-
glucopyranosyl-7-O-a-L-rhamnopyrano-
side (2) except for the presence of a p-
coumaroyl group. The p-coumaroyl group
was assigned to the C-200 hydroxyl group
via an ester bond, which was determined by
the HMBC correlation between H-200 (dH
6.04) and the ester carbonyl at dC 166.9 of
the p-coumaroyl group. Therefore, the
structure of compound 1 was characterized
as kaempferol-3-O-b-D-(2-O-E-p-coumar-
oyl)-glucopyranosyl-7-O-a-L-rhamnopyr-
anoside.
Compounds 2–4, 7, 8, and 10–12
were evaluated for their antimicrobial
activities against Ureaplasma urealyticum
in vitro, but all tested compounds have no
useful activities against Ureaplasma
urealyticum. The minimum inhibitory
concentration (MIC) range of compound
3 was 32–64 mg/ml. The MICs of other
tested compounds were more than
128 mg/ml. Erythromycin served as a
positive control, with the MIC range of
4–8 mg/ml.
Other 11 known compounds (2-12)
were identified as kaempferol-3-O-b-D-
glucopyranosyl-7-O-a-L-rhamnopyrano-
side (2) [3], kaempferol-7-O-a-L-rhamno-
pyranoside (3) [3], kaempferol-3, 7-O-a-
L-dirhamnopyranoside (4) [3], kaemp-
ferol-3-(4-O-acetyl)-O-a-L-rhamnopyra-
nosyl-7-O-a-L-rhamnopyranoside (5) [8],
quercitin-7-O-a-L-rhamnopyranoside (6)
[9], syringin (7) [10], (6S, 7E, 9S)-6, 9,
10-trihydroxy-4, 7-megastigmadien-3-
one-9-O-b-D-glucopyranoside (8) [11],
(6S, 9R)-roseoside (9) [12], epifriedelinol
3. Experimental
3.1 General experimental procedures
Melting points were determined using a
SGW X-4 micromelting point apparatus
(Shanghai Precision Instruments Co., Ltd,
Shanghai, China). Optical rotations were
measured on a PE Model 343 digital
polarimeter (Perkin-Elmer, Waltham, MA,
USA). IR spectra were obtained on a
Nicolet 5700 FT-IR microscope instru-
ment (Thermo Electron Corp., Madison,
WI, USA). UV spectra were determined by
(10) [13], isoarborinol (11) [14], and
dulcitol (12) [15], respectively, by com-
parison of their physical and spectroscopic
data with those values reported in the
literature.
a
JASCO V-650 spectrophotometer
(JASCO, Tokyo, Japan). HR-ESI-MS
data were obtained on an Agilent 6520
Accurate-Mass LC/MS Q-TOF instrument
(Agilent, Santa Clara, CA, USA). NMR

Journal of Asian Natural Products Research
5
spectra were measured on a Bruker
Avance 600 spectrometer (Bruker Biospin,
Fallanden, Switzerland), using TMS as
internal standard. GC data were recorded
on an Agilent 7890A instrument (Agilent).
Precoated silica gel GF254 plates (Qingdao
Marine Chemical Factory, Qingdao,
China) were employed for TLC. For
column chromatography (CC), silica gel
(200–300 mesh, Qingdao Marine Chemi-
cal Factory, Qingdao, China), reversed-
phase C18 silica gel (50 mm, YMC Co. Ltd,
Kyoto, Japan), HPD-100 macroporous
absorbent resin (Hebei Bonherb Technol-
ogy Corp., Cangzhou, China), and Sepha-
dex LH-20 (GE healthcare, Uppsala,
Sweden) were used. The preparative
HPLC were performed on a Varian Pro
Star HPLC system (Varian, Palo Alto, CA,
USA), and a semi-preparative column
(YMC-Pack ODS-A, 20 mm £ 250 mm,
5 mm) was used for separations.
ether (60–908C)-acetone (1:1) from the
Fr. A3 and Fr. A4, respectively. The EtOAc
extract (35 g) was fractioned by Sephadex
LH-20 CC and eluted with MeOH to obtain
three fractions (Fr. B1–Fr. B3). Fr. B1 was
further separated by reversed-phase C18
silica gel CC using a gradient of MeOH–
H2O (2:8–9:1) to yield 8 subfractions (Fr.
B1-1–Fr. B1-8). After further purification
bypreparativeHPLC(MeOH–H2O,45:55),
compound 2 (35 mg, tR ¼ 17.49 min)
was obtained from Fr. B1-5. Separation of
Fr. B1-6 with Sephadex LH-20 CC
(MeOH) gave compound 4 (210 mg).
Compounds 1 (13 mg, tR ¼ 25.63 min), 5
(22 mg, tR ¼ 28.66 min), and 6 (6 mg,
tR ¼ 22.73 min) were obtained from Fr.
B1-8 by preparative HPLC (MeOH–H2O,
1:1). Fr. B2 was applied to Sephadex LH-20
CC, with MeOH as eluent, to achieve
compound 3 (150mg). The aqueous phase
was evaporated in vacuum to give a
supernatant solution (1.8 L) and a precipi-
tation. The precipitation was repeatedly
recrystallizedinMeOH–H2O(1:1)toobtain
compound 12 (11 g). The solution was
subjected to HPD-100 macroporous absor-
bent resin CC using an EtOH/ H2O gradient
(0, 10, 30, 50, and 95% EtOH) to yield five
fractions. The fraction (28 g) eluted by 30%
EtOHwasseparatedonareversed-phaseC18
silica gel column eluting with MeOH–H2O
(1:9–1:0), followed by preparative
HPLC (MeOH–H2O, 15: 85) to afford
compounds 7 (37 mg, tR ¼ 24.18 min), 8
(56 mg, tR ¼ 16.09 min), and 9 (8 mg,
tR ¼ 8.92min).
3.2 Plant material
The aerial parts of Euonymus fortunei
were purchased from Nanning, Guangxi
Zhuang Autonomous Region, China, in
May 2011, and identified by Prof. Xue-
Feng Feng, Institute of Chinese Materia
Medica, China Academy of Chinese
Medical Sciences, where a voucher speci-
men (No. 90820110504) was deposited.
3.3 Extraction and isolation
Dried and powdered aerial parts of
E. fortunei (20 kg) were extracted with
70% EtOH under reflux, and the EtOH
extract was concentrated to dryness. The
residue was suspended in H2O and then
extracted successively with petroleum
ether (60–908C) and EtOAc. The petroleum
ether (60–908C) extract (140g) was sub-
jected to silica gel CC and eluted with
petroleum ether (60–908C)-EtOAc (98:2–
2:8) to yield 17 fractions (Fr. A1–Fr. A17).
Compound 10 (1.65 g) and compound 11
(1.88 g) were recrystallized in petroleum
3.3.1 Compound 1
Pale yellow amorphous powder; mp 211–
20
2128C; ½aꢀD 2 168.0 (c 0.103, MeOH).
UV (MeOH) lmax nm (log 1): 203 (4.69),
269 (4.37), 317 (4.49). IR vmax: 3364,
1702, 1655, 1600, 1513, 1492, 1451, 1172,
832, and 595 cm21 1H and 13C NMR
.
spectral data were listed in Table 1; HR-
ESI-MS m/z: 763.1866 [M þ Na]þ (calcd
for C36H36O17Na, 763.1850).

6
L.-H. Yan et al.
3.4 Acid hydrolysis of compound 1
first row of the micro-titer plate. Serial
dilutions were performed, starting from
0.25 mg/ml to 128 mg/ml. Culture med-
iums (100 ml) were added to all wells of
the micro-titer plate. Negative controls
were included to ensure that the relevant
broth was not contaminated. Erythromycin
served as a positive control. The final MIC
was determined to be the lowest concen-
tration of compound inhibiting color
change after incubation at 378C for 48 h.
According to the reported method [16],
compound 1 (2 mg) was hydrolyzed with 2
M CF3COOH–H2O (2 ml) at 1108C for
3 h. After removal of CF3COOH by
evaporation and extraction with CHCl3,
the H2O extract was evaporated and dried
in vacuo to give the monosaccharide
residue. The residue was dissolved in
pyridine (100 ml), and then 0.06 M L-
cysteine methyl ester hydrochloride-pyr-
idine (100 ml) was added. The mixture was
kept at 608C for 1 h. Next, 150 ml
trimethylsilylation reagent HMDS–
TMCS (hexamethyldisilazane-trimethyl-
chlorosilane, 1:1) was added, and the
resultant reaction mixture was maintained
at 608C for 30 min. After centrifugation,
the supernatant was analyzed by GC under
the following conditions: capillary col-
umn, HP-5 (30 m £ 0.32 mm £ 0.25 mm);
detector, FID (Flame Ionization Detector);
detector temperature, 2808C; injection
temperature, 2508C; initial temperature,
1008C for 2 min and subsequent increase to
2808C at a rate of 108C/min; final
temperature, 2808C for 5 min; carrier, N2
gas. The absolute configurations of the
sugars isolated from the hydrolysate of 1
were determined by comparing the reten-
tion times of their trimethylsilyl-L-
cysteine derivatives with those of auth-
entic sugars prepared by a similar pro-
cedure. The retention times of the
trimethylsilyl-L-cysteine derivatives of
the sugars were as follows: D-glucose,
19.79 min; L-rhamnose, 18.63 min.
Disclosure statement
No potential conflict of interest was reported
by the authors.
Funding
This work was financially supported by the
National Science and Technology Project of
China [No. 2012ZX09304005002], Foundation
of the Chinese Pharmacopeia Commission [No.
2015-Z8] and the Fundamental Research Funds
for the Central Public Welfare Research
Institutes [No. 2011xycz-11].
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