Three new phenolic glycosides from the Tibetan medicinal plant Aconitum tanguticum

Article abstract of DOI:10.1080/10286020.2013.799145

Three new phenolic glycosides, such as (Z)-sinapic acid-4-O-β-d- allopyranoside (1), 3,4-dihydroxyphenethoxy-8-O-β-d-[6-O-(4-O-β-d- glucopyranosyl)-feruloyl]-glucopyranoside (2), and 4-dihydroxyphenethoxy-8-O- β-d-[6-O-(4-O-β-d-glucopyranosyl)-feruloyl]-g

Full text of DOI:10.1080/10286020.2013.799145

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Three new phenolic glycosides from
the Tibetan medicinal plant Aconitum
tanguticum
Lu Xu a b c , Ming Luo a , Li-Me Lin d , Xiao Zhang e , Chun Li a b
Zhi-Min Wang a b & Yong-Ming Luo c
,
a Institute of Chinese Materia Medica, China Academy of Chinese
Medicine Sciences , Beijing , 100700 , China
b National Engineering Laboratory for Quality Control Technology
of Chinese Herbal Medicines , Beijing , 100700 , China
c School of Pharmaceutical Science, Jiangxi University of
Traditional Chinese Medicine , Nanchang , 712046 , China
d School of Pharmaceutical Science, Hunan University of
Traditional Chinese Medicine , Changsha , 410208 , China
e School of Pharmaceutical Science, Zhengzhou University ,
Zhengzhou , 450000 , China
Published online: 14 Jun 2013.
To cite this article: Lu Xu , Ming Luo , Li-Me Lin , Xiao Zhang , Chun Li , Zhi-Min Wang & Yong-Ming
Luo (2013): Three new phenolic glycosides from the Tibetan medicinal plant Aconitum tanguticum ,
Journal of Asian Natural Products Research, DOI:10.1080/10286020.2013.799145
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Journal of Asian Natural Products Research, 2013
http://dx.doi.org/10.1080/10286020.2013.799145
Three new phenolic glycosides from the Tibetan medicinal plant
Aconitum tanguticum
Lu Xuabc, Ming Luoa, Li-Me Lind, Xiao Zhange, Chun Liab*, Zhi-Min Wangab
and Yong-Ming Luoc
aInstitute of Chinese Materia Medica, China Academy of Chinese Medicine Sciences, Beijing
100700, China; National Engineering Laboratory for Quality Control Technology of Chinese
b
c
Herbal Medicines, Beijing 100700, China; School of Pharmaceutical Science, Jiangxi
d
University of Traditional Chinese Medicine, Nanchang 712046, China; School of
Pharmaceutical Science, Hunan University of Traditional Chinese Medicine, Changsha
410208, China; School of Pharmaceutical Science, Zhengzhou University, Zhengzhou
450000, China
e
(Received 18 January 2013; final version received 22 April 2013)
Three new phenolic glycosides, such as (Z)-sinapic acid-4-O-b-D-allopyranoside (1),
3,4-dihydroxyphenethoxy-8-O-b-D-[6-O-(4-O-b-D-glucopyranosyl)-feruloyl]-gluco-
pyranoside (2), and 4-dihydroxyphenethoxy-8-O-b-D-[6-O-(4-O-b-D-glucopyrano-
syl)-feruloyl]-glucopyranoside (3) were isolated from the EtOH extract of whole plant
of Aconitum tanguticum (Maxim.) Stapf. The structures of the new compounds were
1
elucidated by spectroscopic methods, and the total H NMR and 13C NMR chemical
shifts were assigned.
Keywords: Aconitum tanguticum; phenolic glycosides; Ranunculaceae
1. Introduction
2. Results and discussion
Aconitum tanguticum (Maxim.) Stapf.
(Ranunculaceae) is widely used in tra-
ditional Tibet folk medicine for the
treatment of hepatitis, cholecystitis, pneu-
monia, gastroenteritis and cold fever [1].
Previous chemical investigations of A.
tanguticum mainly focused on the iso-
lation and structure elucidation of diterpe-
noid [2–5]. However, in our continuous
study on the chemical constituents of A.
tanguticum [6], three new phenolic glyco-
sides were isolated from the ethanol
extract of the whole plant. The structures
of the new compounds were established on
The 30% EtOH fraction was subjected to
column chromatography (CC) on silica
gel, Sephadex LH-20 (TOSOH Corpor-
ation, Tokyo, Japan), and octadecylsilane
(ODS; YMC Co., Ltd, Kyoto, Japan) to
afford three new phenolic glycosides, such
as 1, 2, and 3, respectively (Figure 1).
Their structures were characterized by
means of spectroscopic methods and
compared with the reported data.
Compound 1 was isolated as a white
amorphous powder. Its molecular formula
was deduced to be C30H38O15 by a positive
HR-ESI-MS at m/z 409.1118 [M þ Na]þ.
The IR spectrum exhibited the absorption
of hydroxyl (3153 cm21) and aromatic
rings (1732 and 1613 cm21). The UV
spectrum showed the absorption maximum
1
the basis of HR-ESI-MS, H NMR, 13C
NMR, and two-dimensional (2D) NMR
spectroscopic methods.
*Corresponding author. Email: wenyeli@yahoo.com.cn
q 2013 Taylor & Francis

2
L. Xu et al.
7
6
H CO
3
8
5
1
'
6
COOH
HOH C
2
9
2
4
O
'
'
4
5
O
3
HO
'
OCH
'
1
3
2
'
3
OH
OH
1
O
2''
7''
H3CO
6'
9''
8''
HO
HO
OH2C
3''
4''
1''
6''
5'
O
6'''
2
4'
7
HOH2C
4'''
O
R
O
O
2'
5'''
2'''
3
1'
1
6
5''
8
HO
3'
OH
HO
1'''
3'''
4
OH
OH
5
2 R=OH; 3 R=H
Figure 1. Structures of compounds 1, 2, and 3.
at 262 nm. 1H NMR spectroscopic data
(Table 1) showed a singlet assignable to a
symmetrical 1,3,4,5-tetrasubstituted aro-
matic ring at dH 7.13 (2H, s, H-2, 6), a pair
of cis-olefinic protons at dH 6.83 (1H, d,
J ¼ 12.6 Hz, H-7) and 5.94 (1H, d,
J ¼ 12.6 Hz, H-8), an anomeric proton at
dH 5.26 (1H, d, J ¼ 7.8 Hz, H-10), and the
aromatic methoxy singlet at dH 3.86 (6H, s,
3, 5-OCH3), which suggested that com-
Table 1. 1H NMR (600 MHz) and 13C (150 MHz) NMR spectroscopic data of compound 1
(CD3OD).
1
Position
dH
dC
1
2
3
4
5
6
7
8
131.3
108.0
152.3
135.9
152.3
108.0
140.7
119.6
168.9
102.2
70.9
71.7
67.3
75.0
61.6
55.6
55.6
7.13 (1H, s)
7.13 (1H, s)
6.83 (1H, d, J ¼ 12.6 6 Hz)
5.94 (1H, d, J ¼ 12.6 6 Hz)
9
10
5.26 (1H, d, J ¼ 7.8 8 Hz)
3.62 (1H, m)
4.15 (1H, m)
3.62 (1H, m)
3.68 (1H, m)
3.68 (1H, m), 3.78 (1H, m)
3.86 (3H, s)
3.86 (3H, s)
20
30
40
50
60
OCH3 (3)
OCH3 (5)

Journal of Asian Natural Products Research
3
pound 1 was a cis-sinapic acid glycoside.
The b-configuration for the sugar unit was
J ¼ 8.0, 1.8 Hz, H-6); an aromatic meth-
oxy singlet at dH 3.80 (3H, s, 300-OCH3);
and two anomeric protons at dH 4.99 (1H,
d, J ¼ 7.2 Hz, H-1000) and 4.23 (1H, d,
J ¼ 7.8 Hz, H-10). Acid hydrolysis of 2
afforded glucose which was confirmed by
thin-layer chromatography (TLC) with an
authentic sample of glucose, and the D-
3
0
0
deduced from its large JH-1/H-2 coupling
constant (7.8 Hz). Acid hydrolysis of 1
liberated a D-allose (tR- -allose 20.005 min)
D
which was determined by gas chromatog-
raphy (GC) analysis [7]. In the HMBC
spectrum, the H-10 proton of b-D-allose
(dH 5.26) showed a correlation with C-4
(dC 135.9). The main HMBC correlations
are shown in Figure 2. Consequently,
compound 1 was determined as (Z)-sinapic
acid-4-O-b-D-allopyranoside.
configuration (tR- -glucose 19.849 min) was
D
determined by GC analysis [7]. The b-
anomeric configurations for the two
glucoses were deduced from their large
3
00
00
JH-1/H-2 coupling constants 7.8 and
7.2 Hz. The 13C NMR spectrum showed a
group of characteristic signals due to a
feruloyl group at dC 128.4 (C-100), 111.4
(C-200), 149.6 (C-300), 149.0 (C-400), 115.3
(C-500), 123.2 (C-600), 145.2 (C-700), 116.7
(C-800), and 167.0 (C-900) [8], and a group
of characteristic signals due to a 3,4-
dihydroxyphenethyl ethanol at dC 129.6
(C-1), 116.3 (C-2), 145.4 (C-3), 144.0 (C-
4), 115.9 (C-5), 119.9 (C-6), 35.6 (C-7),
and 70.4 (C-8). A series of HMBC
correlations from the anomeric proton H-
10 (dH 4.23) to C-8 (dC 70.4); from H-2 (dH
6.60) to C-7 (dC 35.6), C-4 (dC 144.0), and
C-6 (dC 119.9); from H-5 (dH 6.60) to C-1
(dC 129.6) and C-3 (dC 145.4); and from
H-6 (dH 6.46) to C-7 (dC 35.6), C-2 (dC
116.3), and C-4 (dC 144.0) indicated the
Compound 2 was isolated as a white
amorphous powder. Its positive ion HR-
ESI-MS showed a quasimolecular ion
peak at m/z 677.2028 [M þ Na]þ, corre-
sponding to the molecular formula
C30H38O16. The IR spectrum exhibited
the absorptions of hydroxyl (3396 cm21),
carbonyl (1712 cm21), and aromatic rings
(1634 and 1511 cm21). The UV spectrum
showed the absorption maxima at 289 and
1
320 nm. The H NMR spectroscopic data
showed two groups of aromatic protons of
ABX coupling relations attributed to two
1,3,4-trisubstituted aromatic rings at dH
7.37 (1H, d, J ¼ 1.6 Hz, H-200), 7.07 (1H,
d, J ¼ 8.5 Hz, H-500), and 7.13 (1H, dd,
J ¼ 8.5, 1.6 Hz, H-600) and dH 6.60 (1H, m,
H-2), 6.60 (1H, m, H-5), and 6.46 (1H, dd,
H
H
H3CO
COOH
H
HOH2C
HO
O
O
OCH3
OH
OH
H
1
H
O
H
H
H3CO
O
C
H
O
HOH2C
HO
HO
O
R
O
HO
O
OH
HO
H
H
OH
H
OH
2
Figure 2. Key HMBC correlations (H ! C) in compounds 1 and 2.

4
L. Xu et al.
3,4-dihydroxyphenethoxy-O-b-D-gluco-
pyranoside moiety in 2. A list of HMBC
correlations from the anomeric proton H-
1000 (dH 4.99) to C-400 (dC 149.0); from H-200
(dH 7.37) to C-700 (dC 145.2), C-400 (dC
149.0), and C-600 (dC 123.2); from H-500 (dH
7.07) to C-100 (dC 128.4) and C-300 (dC
149.6); from H-600 (dH 7.13) to C-200 (dC
111.4) and C-400 (dC 149.0); and from H-800
(dH 6.60) to C-100 (dC 128.4) demonstrated
the (4-O-b-D-glucopyranosyl)-feruloyl
moiety in 2. The main HMBC
correlations are shown in Figure 2.
Furthermore, the deshielded 60-methylene
protons [dH 4.39 (1H, d, J ¼ 10.4 Hz, H-
60a), 4.21 (1H, dd, J ¼ 10.4, 6.1 Hz, H-
60b)] of the glucose moiety, due to the
esterification of the feruloyl group,
suggested that the O-feruloyl group was
attached to C-60, which was supported by
the HMBC correlation between H-60 and
C-900 (dC 167.0). Therefore, the structure of
2 was elucidated as 3,4-dihydroxyphe-
nethoxy-8-O-b-D-[6-O-(4-O-b-D-gluco-
pyranosyl)-feruloyl]-glucopyranoside.
experiments resulted in the assignments of
all NMR signals and the linkage of the
structural units of 3. Consequently, 3 was
established as 4-hydroxyphenethoxy-8-O-
b-D-[6-O-(4-O-b-D-glucopyranosyl)-feru-
loyl]-glucopyranoside.
3. Experimental
3.1 General experimental procedures
Melting point (mp) was determined on an
X-4 micromelting point apparatus (Cany
Precision Instruments Co., Ltd, Shanghai,
China). IR spectra were recorded on a
Nicolet 5700 FT-IR spectrometer (Thermo
Nicolet Corporation, Madison, WI, USA).
UV spectra were measured on T6 New
Century UV–vis spectrophotometer
(Pgeneral, Beijing, China). NMR spectra
were recorded on a Bruker Advance 600
spectrometer (Bruker, Switzerland). HR-
ESI-MS data were recorded on Agilent
Technologies 6250 Accurate-Mass Q-TOF
LC/MS spectrometer (Santa Clara, CA,
USA). ESI-MS were measured on an
Agilent 6130SQ-MSD (Agilent Technol-
ogies). GC data were recorded on an
Agilent 7890A instrument with a flame
ionization detector (FID; Agilent 6130SQ-
MSD). Preparative high-performance
liquid chromatography (HPLC) was per-
formed on an LC3000 instrument (Beijing
Chuangxintongheng Science and Technol-
ogy Co., Ltd, Beijing, China) connected to
a UV 3000 detector, using an Intersil-ODS
column (250 £ 20 mm, 10 mm; GL
Sciences Inc., Tokyo, Japan). TLC plate
precoated with silica gel GF254
(20 £ 20 cm) was produced by Merck
company (Darmstadt, Germany). ODS
(50 mm), silica gel (200–300 mesh;
Qingdao Marine Chemical Industry, Qing-
dao, China), and AB-8 macroporous
adsorption resin (The Chemical Plant of
Nankai University, Tianjin, China) were
used for CC. Spots were visualized under
UV light or by spraying with 10% H2SO4
in EtOH–H2O (95:5, v/v) followed
by heating. Solvents [petroleum ether
Compound 3 was also isolated as a
white amorphous powder. Its molecular
formula was deduced to be C30H38O15 by a
positive HR-ESI-MS at m/z 661.20766
[M þ Na]þ. The IR spectrum exhibited
the absorptions of hydroxyl (3369 cm21),
carbonyl (1722 cm21), and aromatic rings
(1639 and 1599 cm21). The UV spectrum
showed the absorption maxima at 280 and
325 nm. The 1H NMR and 13C NMR
spectroscopic data indicated the presence
of p-hydroxyphenyl ethanol group [dH
7.01 (2H, d, J ¼ 8.4 Hz, H-2, 6), 6.62 (2H,
d, J ¼ 8.4 Hz, H-3, 5), 2.72 (2H, m, H-7),
3.80 (1H, m, H-8a), and 3.51 (1H, m, H-
8b) and dC 129.0 (C-1), 130.0 (C-2, 6),
115.5 (C-3, 5), 156.1 (C-4), 35.6 (C-7),
and 70.5 (C-8)]. Comparison of the NMR
spectroscopic data of 3 with those of 2
indicated that the structure of 3 was very
close to that of 2, except that the 3,4-
dihydroxyphenyl ethanol group in 2 was
substituted by the p-hydroxyphenyl etha-
nol group in 3. Moreover, the 2D NMR

Journal of Asian Natural Products Research
5
(60–908C), CHCl3, EtOAc, MeOH,
CH2Cl2, and EtOH] were of analytical
grade and purchased from Beijing Chemi-
cal Company (Beijing, China).
ODS CC with gradient MeOH–H2O
(2:8/3:7/10:0) to give Frs X.1–X.10. Fr.
X.10 (391 mg) was purified on silica gel
CC using the gradient CHCl3–MeOH–
H2O (9:1:0.05/8:2:0.125/7:3:0.5/6:4:1) to
afford 2 (12 mg) and 3 (10 mg).
3.2 Plant material
The whole plant of A. tanguticum (col-
lected from Qinghai Province, China, in
August 2010) was bought from Xining
Sanjiangbao Trade Co., Ltd (Qinghai,
China) and identified by the researcher
Xue-feng Feng of the Institute of Chinese
Materia Medica, China Academy of
Chinese Medical Sciences (Beijing,
China). The specimen (No. 20100813)
was deposited in the Institute of Chinese
Materia Medica, China Academy of
Chinese Medical Sciences.
3.3.1 (Z)-Sinapic acid-4-O-b-D-
allopyranoside (1)
White powder; mp 1698C; UV (MeOH)
lmax: 262 nm. IR (KBr) nmax: 3153, 1732,
1613 cm21. For 1H NMR (DMSO-d6,
600 MHz) and 13C NMR (DMSO-d6,
150 MHz) spectral data, see Table 1. (þ)
ESI-MS (m/z): 409 [M þ Na]þ; (2) ESI-
MS (m/z): 385 [M–H]2, 771 [2M–H]2.
HR-ESI-MS: m/z 409.1118 [M þ Na]þ
(calcd for C17H22O10Na, 409.1111).
3.3 Extraction and isolation
3.3.2 3,4-Dihydroxyphenethoxy-8-O-b-
D-[6-O-(4-O-b-D-glucopyranosyl)-
feruloyl]-glucopyranoside (2)
Dried and powdered plants of A. tanguti-
cum (10 kg) were extracted with 95%
EtOH under reflux, and the EtOH extract
was concentrated to dryness. The residue
(1.8 kg) was suspended in H2O and then
extracted with petroleum ether and EtOAc.
The residual aqueous solution was chro-
matographed over macroporous resin AB-
8 with H2O containing increasing amounts
of EtOH as eluent to afford (A) H2O eluate
(605 g), (B) 30% EtOH eluate (407.9 g),
(C) 60% EtOH eluate (107.0 g), and (D)
95% EtOH eluate (2.3 g). Fraction B was
chromatographed on silica gel and gradi-
ently eluted with CHCl3–MeOH–H2O
(8:2:0.125/7:3:0.5/6:4:1/5:5:1) to give
fractions (Frs) I–X. Fr. V (61.7 g) was
submitted to a silica gel CC eluted with
CHCl3–MeOH–H2O (7:3:0.5) to afford
Frs V-1–V-14. Fr. V-3 (638 mg) was
separated by preparative HPLC using
MeOH–0.1% formic acid aqueous sol-
ution (22:78, 10 ml min21, 210 nm) to
yield 1 (39 mg, tR 46 min). Fr. X (31.5 g)
was repeatedly purified on silica gel CC
using the gradient CHCl3–MeOH–H2O
(7:3:0.5/65:35:10/6:4:1/5:5:1) followed by
White amorphous powder; mp 2248C; UV
(MeOH) lmax: 289, 320 nm. IR (KBr)
n
max: 3396, 1712, 1634, 1511 cm21. For
1H NMR (DMSO-d6, 600 MHz) and 13C
NMR (DMSO-d6, 150 MHz) spectral data,
see Table 2. (þ) ESI-MS (m/z): 677
[M þ Na]þ, (2) ESI-MS (m/z): 653 [M–
H]2. HR-ESI-MS: m/z 677.2028
[M þ Na]þ (calcd for C30H38O16Na,
677.2060).
3.3.3 4-Hydroxyphenethoxy-8-O-b-D-
[6-O-(4-O-b-D-glucopyranosyl)-feruloyl]-
glucopyranoside (3)
White amorphous powder; mp 2048C; UV
(MeOH) lmax: 280, 325 nm. IR (KBr)
n
max: 3369, 1722, 1639, 1599 cm21. For
1H NMR (DMSO-d6, 600 MHz) and 13C
NMR (DMSO-d6, 150 MHz) spectral data,
see Table 2. (þ) ESI-MS (m/z): 661
[M þ Na]þ; (2) ESI-MS (m/z): 637 [M–
H]2. HR-ESI-MS: m/z 661.2077
[M þ Na]þ (calcd for C30H38O15Na,
661.2108).

6
L. Xu et al.
Table 2. 1H NMR (600 MHz) and 13C NMR (150 MHz) spectroscopic data of compounds 2 and 3
(DMSO-d6).
2
3
Position
dH
dC
dH
dC
1
2
3
4
5
6
129.6
116.3
145.4
144.0
115.9
119.9
129.0
130.0
115.5
156.1
115.5
130.0
6.60 (1H, m)
7.01 (1H, d, J ¼ 8.4 Hz)
6.62 (1H, d, J ¼ 8.4 Hz)
6.60 (1H, m)
6.46 (1H, dd,
6.62 (1H, d, J ¼ 8.4 Hz)
7.01 (1H, d, J ¼ 8.4 Hz)
J ¼ 8.0, 1.8 Hz)
7
8
2.66 (2H, m)
3.57 (1H, d, J ¼ 7.0 Hz),
35.6
70.4
2.72 (2H, m)
3.51 (1H, m), 3.80 (1H, m)
35.6
70.5
3.78 (1H, m)
10
20
30
40
50
60
4.23 (1H, d, J ¼ 7.8 Hz)
3.00 (1H, m)
3.17 (1H, m)
3.17 (1H, m)
3.32 (1H, m)
103.5
73.6
77.0
70.0
77.3
64.1
4.24 (1H, d, J ¼ 7.8 Hz)
3.00 (1H, m)
3.17 (1H, m)
3.17 (1H, m)
3.32 (1H, m)
103.5
73.6
77.0
70.0
77.3
64.1
4.21 (1H, dd, J ¼ 10.4, 6.1 Hz),
4.21 (1H, dd, J ¼ 10.4,
4.39 (1H, d, J ¼ 10.4 Hz)
6.4 Hz), 4.38
(1H, d, J ¼ 10.4 Hz)
100
200
300
400
500
600
700
800
900
1000
2000
3000
4000
500
6000
128.4
111.4
149.6
149.0
115.3
123.2
145.2
116.7
167.0
100.0
73.8
128.4
111.5
149.6
149.0
115.3
123.2
145.2
116.4
167.0
100.0
73.8
7.37 (1H, d, J ¼ 1.6 Hz)
7.37 (1H, d, J ¼ 1.6 Hz)
7.07 (1H, d, J ¼ 8.5 Hz)
7.13 (1H, dd, J ¼ 1.6 Hz)
7.57 (1H, d, J ¼ 15.8 Hz)
6.60 (1H, m)
7.07 (1H, d, J ¼ 8.5 Hz)
7.14 (1H, dd, J ¼ 8.5, 1.6 Hz)
7.58 (1H, d, J ¼ 15.8 Hz)
6.60 (1H, d, J ¼ 15.8 Hz)
4.99 (1H, d, J ¼ 7.2 Hz)
3.26 (1H, m)
3.26 (1H, m)
3.17 (1H, m)
3.32 (1H, m)
4.99 (1H, d, J ¼ 7.2 Hz)
3.26 (1H, m)
3.26 (1H, m)
77.3
70.7
77.5
61.1
77.3
70.6
77.5
61.1
3.17 (1H, m)
3.32 (1H, m)
3.41 (1H,m), 3.52 (1H, m)
3.45 (1H, m),
3.66 (1H, d, J ¼ 11.4 Hz)
OCH3
3.80 (3H, s)
56.2
3.81 (3H, s)
56.2
3.4 Determination of the absolute
configuration of the sugar moieties
heated at 608C for 2 h, then evaporated
under N2 stream and dried in vacuo. The
residue was dissolved in 0.2 ml of N-
trimethylsilylimidazole and heated at 608C
for 1 h. The reaction mixture was parti-
tioned between n-hexane and H2O (2 ml
each), and the n-hexane extract was
analyzed by GC (Agilent 7890A) under
the following conditions: capillary column
HP-5 (30 m £ 0.32 mm £ 0.25 mm); detec-
tor FID; carrier gas N2 (flow rate
According to the reported method [7], each
(2 mg) of the compounds 1, 2, and 3 was
hydrolyzed by 2 M HCl–H2O (2 ml) at
908C for 4 h. After removal of HCl 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 (1 ml) containing L-cysteine
methyl ester hydrochloride (2 mg) and
1 ml min21);
detector
temperature

Journal of Asian Natural Products Research
(2808C); injection temperature (2508C); References
7
and oven temperature gradient: 1008C for
2 min, 100 ! 2808C (108C min21), and
2808C for 5 min. The same procedure was
applied to authentic samples. By compari-
son with the retention time of the authentic
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cine (Nationalities Publishing House, Beij-
ing, 1997), p. 65.
[2] H.Q. Wang, S.H. Jiang, P.M. Yang, M.H.
Ying, S.J. Lin, and D.Y. Zhu, Nat. Prod.
Res. Dev. 14, 13 (2002).
sample (tR- -glucose, 19.849 min; tR- -glucose
,
19.822 min; tR- -allose, 20.005 min; and tR-
D
L
[3] L. Lin, D.L. Chen, X.Y. Liu, Q.H. Chen,
F.P. Wang, and C.Y. Yang, Nat. Prod.
Commun. 4, 897 (2009).
D
,
20.415 min), D-allose (tR:
L
-allose
20.005 min) was identified in the acid
hydrolysate of 1 and D-glucose (tR:
19.847 min) was identified in the acid
hydrolysates of 2 and 3.
[4] L. Li, J.F. Zhao, Y.B. Wang, and H.B.
Zhang, Helv. Chim. Acta 87, 866 (2004).
[5] B.S. Josh, Y.L. Baia, D.H. Chen, and S.W.
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(1993).
[6] M. Luo, L.M. Lin, C. Li, and Z.M. Wang,
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[7] J. Bai, Z.F. Fang, H. Chen, S.S. Yu, D.
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Acknowledgements
This project was financially supported by
Beijing
Natural
Science
Foundation
(7132152) and the Fundamental Research
Funds for the Central Public Welfare Research
Institutes (ZZ070828). The authors are grateful
to the Department of Instrumental Analysis of
Beijing University of Chemical Technology for
the NMR measurements.
[8] B.J. Park and M. Tomohiko, Chem. Nat.
Compd. 3, 363 (2011).