A new lignan glycoside from the stems of Zanthoxylum armatum DC

Article abstract of DOI:10.1080/14786419.2016.1205064

A new lignan glycoside, (7S,8R)-guaiacylglycerol-ferulic acid ether-7-O-β-D-glucopyranoside (1), along with five known phenylpropanoids (2–6) and seven phenylpropanoid glycosides (7–13), were isolated from the stems of Zanthoxylum armatum DC. Their structures were elucidated by spectroscopic analysis. Compounds 2–8 and 11–13 were first isolated from Rutaceae and the others were isolated for the first time from Z. armatum.

Full text of DOI:10.1080/14786419.2016.1205064

Natural Product Research
Formerly Natural Product Letters
ISSN: 1478-6419 (Print) 1478-6427 (Online) Journal homepage: http://www.tandfonline.com/loi/gnpl20
A new lignan glycoside from the stems of
Zanthoxylum armatum DC
Tao Guo, Xiao-Feng Tang, Jun Chang & Ya Wang
To cite this article: Tao Guo, Xiao-Feng Tang, Jun Chang & Ya Wang (2016): A new lignan
glycoside from the stems of Zanthoxylum armatum DC, Natural Product Research, DOI:
10.1080/14786419.2016.1205064
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Date: 21 July 2016, At: 22:24

Natural Product research, 2016
ꢁꢁp://ꢂx.ꢂꢃi.ꢃꢄg/10.1080/14786419.2016.1205064
ꢀ
A new lignan glycoside from the stems of Zanthoxylum
armatum DC
Tao Guoa,b,† , Xiao-Feng Tang , Jun Chang and Ya Wang
a,†
b
a
ꢅ
b
sꢆꢀꢃꢃꢇ ꢃf lifꢈ sꢆiꢈnꢆꢈ ꢅnꢂ enginꢈꢈꢄing, lꢅnzꢀꢃꢉ univꢈꢄꢊiꢁy ꢃf tꢈꢆꢀnꢃꢇꢃgy, lꢅnzꢀꢃꢉ, cꢀinꢅ; sꢆꢀꢃꢃꢇ ꢃf
Pꢀꢅꢄmꢅꢆy, Fꢉꢂꢅn univꢈꢄꢊiꢁy, sꢀꢅngꢀꢅi, cꢀinꢅ
ABSTRACT
ARTICLE HISTORY
A new lignan glycoside, (7S,8R)-guaiacylglycerol-ferulic acid ether-7-
O-β-D-glucopyranoside (1), along with five known phenylpropanoids
rꢈꢆꢈivꢈꢂ 20 Fꢈbꢄꢉꢅꢄy 2016
aꢆꢆꢈpꢁꢈꢂ 3 Jꢉnꢈ 2016
(
2–6) and seven phenylpropanoid glycosides (7–13), were isolated
KEYWORDS
from the stems of Zanthoxylum armatum DC. Their structures were
elucidated by spectroscopic analysis. Compounds 2–8 and 11–13
were first isolated from Rutaceae and the others were isolated for
the first time from Z. armatum.
Zanthoxylum armatum;
rꢉꢁꢅꢆꢈꢅꢈ; ꢇignꢅn gꢇyꢆꢃꢊiꢂꢈ;
pꢀꢈnyꢇpꢄꢃpꢅnꢃiꢂ;
pꢀꢈnyꢇpꢄꢃpꢅnꢃiꢂ gꢇyꢆꢃꢊiꢂꢈ
1
. Introduction
The genus Zanthoxylum (Rutaceae) comprises 250 species distributed in the tropical and
subtropical zones of Asia, Africa, America and Oceania, and there are 39 species and 14
varieties in China. Z. armatum DC is a wild shrub distributed mainly in southeast Asia, the
Himalayas and China. It has a long history to be used in folk medicines to treat abdominal
pain, cold and cough, tonsillitis, fever, altitude sickness, diarrhoea and dysentery. Recent
studies have demonstrated the extract of Z. armatum possesses anti-proliferative (Kumar &
Müller 1999), anti-inflammatory (Bhatt & Upadhyaya 2010), antioxidant (Kanwal et al. 2015;
Zhang et al. 2015), hepatoprotective (Verma & Khosa 2010), antinociceptive (Guo et al. 2011;
Ibrar et al. 2012), antidiabetic (Karki et al. 2014) and larvicidal activities (Kumar et al. 2016).
The essential oil of Z. armatum exhibited good antimicrobial and anthelmintic activities
(
Barkatullah et al. 2013). Several kinds of compounds, including lignan, alkaloid, enoic acid,
flavonoid, coumarin and amide have been isolated from the plant (Ahmad et al. 2004;
CONTACT Jꢉn cꢀꢅng
jꢆꢀꢅng@fꢉꢂꢅn.ꢈꢂꢉ.ꢆn
sꢉppꢇꢈmꢈnꢁꢅꢇ ꢂꢅꢁꢅ fꢃꢄ ꢁꢀiꢊ ꢅꢄꢁiꢆꢇꢈ ꢆꢅn bꢈ ꢅꢆꢆꢈꢊꢊꢈꢂ ꢅꢁ ꢀꢁꢁp://ꢂx.ꢂꢃi.ꢃꢄg/10.1080/14786419.2016.1205064.
†
tꢀꢈ bꢃꢁꢀ ꢅꢉꢁꢀꢃꢄꢊ ꢆꢃnꢁꢄibꢉꢁꢈꢂ ꢈqꢉꢅꢇꢇy ꢁꢃ ꢁꢀiꢊ wꢃꢄk.
©
2016 Infꢃꢄmꢅ uK limiꢁꢈꢂ, ꢁꢄꢅꢂing ꢅꢊ tꢅyꢇꢃꢄ & Fꢄꢅnꢆiꢊ Gꢄꢃꢉp

2
T. GUO ꢀT Aꢁ.
Figure 1. cꢀꢈmiꢆꢅꢇ ꢊꢁꢄꢉꢆꢁꢉꢄꢈꢊ ꢃf ꢆꢃmpꢃꢉnꢂꢊ 1–13 iꢊꢃꢇꢅꢁꢈꢂ fꢄꢃm ꢁꢀꢈ ꢊꢁꢈmꢊ ꢃf Z. armatum.
ꢁ
2
i et al. 1996; Kalia et al. 1999; ꢁi et al. 2006; Singh & Singh 2011; Guo et al. 2012; Mehta et al.
012; Devkota et al. 2013; Samad et al. 2014, 2015). However, the hydrophilic fraction of Z.
armatum was rarely reported.
As a part of our systematic investigation on chemical constituents of Z. armatum, a new
lignan glycoside, (7S,8R)-guaiacylglycerol-ferulic acid ether-7-O-β-D-glucopyranoside (1),
along with five known phenylpropanoids (2–6) and seven phenylpropanoid glycosides
(7–13), were isolated from the stems of Z. armatum (Figure 1). Their structures were elucidated
by spectroscopic analysis.
2
. Result and discussion
Compound 1 was obtained as colourless oil. Its molecular formula was determined as
+
1
C H O by HR-ꢀSI-MS at m/z 575.1739 [M + Na] , possessing 11° of unsaturation. The H
2
6
32 13
NMR spectrum of 1 (Table S1) showed six aromatic protons of two ABX type [δ 7.01 (1H, d,
J = 1.7 Hz, H-2), 6.91 (1H, dd, J = 8.8, 1.7 Hz, H-6), 6.82 (1H, d, J = 8.8 Hz, H-5), 7.17 (1H, d,
J = 1.7 Hz, H-2′), 6.99 (1H, dd, J = 8.8, 1.7 Hz, H-6′), 6.81 (1H, d, J = 8.8 Hz, H-5′)] in the low
field. Two olefin protons [δ 7.25 (1H, d, J = 16 Hz, H-7′), 6.35 (1H, d, J = 16 Hz, H-8′)] indicated
the presence of trans double bond. There are one methylene proton [δ 3.68 (2H, m)], two
methine protons [δ 5.03 (1H, d, J = 4.5 Hz), 3.86 (1H, m)] and one glucopyranosyl anomeric
1
3
proton [δ 4.61 (1H, d, J = 7.6 Hz)]. In the C NMR spectrum, the presence of two C –C units
6
3
arising from lignan and a glucopyranose was suggested. The proton and carbon signals were
1
1
assigned with the H– H COSY, HMBC and HMQC. The correlation site between the guaia-
cylglycerol and the ferulic acid moiety was established by a HMBC experiment (Figure S1)
in which the long-range correlation between H-8 (δ 3.86) and C-4′ (δ 147.5) was observed.
Acid hydrolysis of 1 with 5% HCl afforded
d-glucose, which compared with authentic samples.
The stereochemistry of the anomeric carbon of glucose was determined as β according to

NATURAꢁ PRODUCT RꢀSꢀARCH
3
the coupling constant of the anomeric proton and the chemical shift of C-1″ (102.3). The
glycosidic site was unambiguously established by a HMBC experiment in which the long-
range correlation between H-1″ (δ 4.61) and C-7 (δ 79.7) was observed. The small coupling
1
constant (J7,8 = 4.5 Hz) in the H NMR spectrum indicated a erythro configuration between
H-7 and H-8. The CD spectrum of 1 showed a negative Cotton effect at 238 nm, together
with the clear NOꢀSY correlations between H-8/H-2 and H-8/H-6 (Figure S1), indicated the
7S,8R-configuration (Matsuda & Kikuchi 1996; Hu et al. 2012). Finally, structure of 1 was
defined as (7S,8R)-guaiacylglycerol-β-ferulic acid ether-7-O-β-d-glucopyranoside.
Twelve known compounds were identified as erythro-1-(4-hydroxyphenyl) glycerol (2)
(
(
ꢁundgren et al. 1985), thero-syringylglycerol (3) (Otsuka et al. 1989), erythro-syringylglycerol
4) (ꢁin et al. 2007), 7-(3-hydroxy-5-methoxyphenyl) propane-7,8,9-triol (5) (Zeng et al. 2012),
threo-guaiacylglycerol (6) (Okyuama et al. 1998), (-)-(7R,8S)-guaiacylglycerol 8-O-β-d-
glucopyranoside (7) (Ishimaru et al. 1987), xylocoside A (8) (Zheng et al. 2008), syringin (9)
(
Calis et al. 1993), coniferin (10) (Calis et al. 1993), 3-hydroxy-2-{4-[(1ꢀ)-3-hydroxyprop-1-
en-1-yl] -2-methoxyphenoxy}propyl-d-glucopyranoside (11) (ꢁiu et al. 2009), psoralenoside
12) (Qiao et al. 2006) and isopsoralenoside (13) (Qiao et al. 2006). Their structures were
(
established on the basis of spectral and chemical evidence, which were in good agreement
with those reported in the literature. Among that, compounds 2–8 and 11–13 were first
isolated from Rutaceae and others were isolated for the first time from Z. armatum.
3
. Experimental
3
.1. General experimental producers
Optical rotation data were obtained on a Perkin-ꢀlmer 241 automatic digital polarimeter.
UV spectral data were measured on a Shimadzu UV-260 instrument. Optical rotations were
1
13
1
1
measured on a JASCO P-1020 spectropolarimeter (JASCO, Tokyo, Japan). H, C NMR, H– H
COSY, HMQC, HMBC and NOꢀSY spectra were recorded on a Bruker DRX-400 spectrometer
1
13
(
H 400 MHz and C 100 MHz). The carbon multiplicities were obtained by DꢀPT experiment.
HR-ꢀSI-MS data were measured on Bruker APꢀX 7.0 TꢀSꢁA FT-MS apparatus (Bruker, Axs
Gmbh, Switzerland). Reversed-phase chromatography utilised TSK gel Toyopearl HW-40F
(
ꢁ
30–60 μm, Toso Co., ꢁtd.), MCI gel CHP 20P (75–150 μm, Mitsubishi Chemical Industries Co.,
td.) and Cosmosil 75 C -OPN (42–105 μm, NacalaiTesque Inc.) columns. TꢁC was performed
18
using precoated silica gel 60 F254 plates (0.2 mm, Merck).
3
.2. Plant materials
The stems of Z. armatum DC. was collected from Nanning of Guangxi Province, China in
September 2014, and identified by associate professor Ze-hao Huang, and a voucher spec-
imen of the plant (#Z140934) was deposited in school of life science and engineering,
ꢁ
anzhou University of Technology, Gansu, China.
3
.3. Extraction and isolation
The air-dried stems of Z. armatum fruits (20 kg) were extracted three times with 40 ꢁ of 95%
ethanol at room temperature, each for 4 days. The solvent was concentrated under reduced
pressure to give a residue. The residue was suspended in water (2 ꢁ) and extracted with

4
T. GUO ꢀT Aꢁ.
petroleum ether, ꢀtOAc and n-BuOH, successively. The water soluble fraction (83 g) dissolved
in 300 mꢁ water was subjected to MCI gel CHP 20P (8 × 60 cm) and eluted with MeOH/H O
2
to obtain fraction 1 [1.0 ꢁ, H O], fraction 2 [0.6 ꢁ, MeOH/H O (10:90)], fraction 3 [0.6 ꢁ, MeOH/
2
2
H O (30:70)], fraction 4 [0.6 ꢁ, MeOH/H O (50:50)], fraction 5 [0.6 ꢁ, MeOH/H O (70:30)],
2
2
2
fraction 6 [1.0 ꢁ, MeOH]. Fraction 2 (12.9 g) was chromatographed on Toyopearl HW-40F
6 × 60 cm) using H O obtained fractions 2A–2ꢀ. Fraction 2B (0.9 g) was further purified by
(
2
Cosmosil 75 C -OPN (4 × 30 cm, eluted with H O → 10% MeOH) and MCI gel CHP 20P
1
8
2
(
5 × 40 cm, eluted with H O → 10% MeOH) to yield 7 (63.0 mg) and 6 (143.3 mg). Fraction
2
2
C (0.3 g) was subjected to MCI gel CHP 20P (5 × 40 cm, eluted with H O → 10% MeOH), then
2
separated by Toyopearl HW-40F (6 × 60 cm, eluted with H O) to give 5 (53.9 mg) and 2
2
(
9.2 mg). Fraction 3 (8.9 g) was subjected to Toyopearl HW-40F (6 × 60 cm, eluted with H O)
2
to obtained fraction 3A–3D. Fraction 3B (0.3 g) was further purified by MCI gel CHP 20P
5 × 40 cm, eluted with H O-20% MeOH) and Cosmosil 75 C -OPN (4 × 30 cm, eluted with
(
2
18
H O → 20% MeOH) to give 4 (6.5 mg) and 8 (10.2 mg). Fraction 3C (0.2 g) was chromato-
2
graphed on MCI gel CHP 20P (5 × 40 cm, eluted with H O → 20% MeOH) to yield 3 (23.2 mg).
2
Fraction 4 (9.4 g) was chromatographed on Toyopearl HW-40F (6 × 60 cm, eluted with H O)
2
to yield six fractions 4A–4F. Fraction 4C (0.2 g) was further purified by MCI gel CHP 20P
(
5 × 40 cm, eluted with 30–50% MeOH) and Cosmosil 75 C -OPN (4 × 30 cm, eluted with
18
30 → 50% MeOH) to give 9 (6.2 mg) and 11 (5 mg). Fraction 4D (0.1 g) was further purified
by Cosmosil 75 C -OPN (4 × 30 cm, eluted with 30 → 50% MeOH) and Toyopearl HW-40F
1
8
(
6 × 60 cm, eluted with H O) to give 10 (6.5 mg). Fraction 5 (5.8 g) was separated byToyopearl
2
HW-40F (6 × 60 cm) using H O as eluent to obtained fractions 5A–5C. Fraction 5B (0.3 g) was
2
further purified by Cosmosil 75 C -OPN (4 × 30 cm, eluted with 40% → 70% MeOH) and
1
8
Toyopearl HW-40F (6 × 60 cm, eluted with H O) to yield 12 (18.9 mg), 13 (7.4 mg) and 1
2
(
13.2 mg).
Compound 1: colourless oil.[ꢀ]D − 69.3 (c 0.10, H O); HR-ꢀSI-MS m/z 575.1739 [M + Na]+
2
0
◦
2
1
13
(Calcd for C H O Na, 575.1741); H and C NMR: see Table S1.
2
6
32 13
3
.4. Acid hydrolysis of 1
A solution of compounds 1 (1 mg) in 5% HCl (0.5 mꢁ) was heated (90 °C) for 2 h. After remov-
ing HCl by evaporation in vacuum, the mixture was diluted with H O and extracted with
2
ꢀtOAc. The aqueous layer was neutralised with 0.1 M NaOH and glucose was detected by
TꢁC analysis with authentic sugars: CHCl –MeOH–H O (14:6:1), Rf 0.13 (glucose); n-BuOH-
3
2
pyridine-H O (6:4:3), Rf 0.37 (glucose).
2
4
. Conclusion
The Z. armatum (Rutaceae) is widely distributed in China, which has been used as Traditional
Chinese Medicine. Chemical study on the stems of Z. armatum has resulted in the isolation
of a new phenylpropanoid glycoside, (7S,8R)-guaiacylglycerol-β-ferulic acid ether-7-O-β-d-
glucopyranoside (1), along with 12 known compounds. Compounds 2–8 and 11–13 were
first isolated from Rutaceae and others were isolated for the first time from Z. armatum.

NATURAꢁ PRODUCT RꢀSꢀARCH
5
Supplementary material
Supplementary material relating to this article is available online, alongsideTables S1 and Figures S1–S5.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
This research was supported by the National Natural Science Foundation of China [grant number
81360476].
ORCID
Tao Guo
http://orcid.org/0000-0003-4502-5570
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