Smilasides M and N, two new phenylpropanoid glycosides from Smilax riparia

Article abstract of DOI:10.1080/10286020.2011.641536

Two new phenylpropanoid glycosides, smilasides M and N, together with the known compound 2,6-diacetyl-3,6-diferuloylsucrose, were isolated and characterized from the roots and rhizomes of Smilax riparia A. DC. The structures of the new compounds were elucidated as 2,6-diacetyl-3-Z-feruloyl-6- feruloylsucrose (1) and 2,6-diacetyl-3-feruloyl-6-Z-feruloylsucrose (2) on the basis of extensive analysis of HR-ESI-MS, UV, IR, and 1D and 2D NMR spectroscopic data.

Full text of DOI:10.1080/10286020.2011.641536

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Smilasides M and N, two new
phenylpropanoid glycosides from Smilax
riparia
Ting-Ting Sun a , Dian-Wen Zhang a , Yan Han a , Fang-Yan Dong a &
Wei Wang a
a Institute of Phytochemistry, Jilin Academy of Chinese Medicine
Sciences, Changchun, 130012, China
Published online: 01 Feb 2012.
To cite this article: Ting-Ting Sun , Dian-Wen Zhang , Yan Han , Fang-Yan Dong & Wei Wang (2012):
Smilasides M and N, two new phenylpropanoid glycosides from Smilax riparia , Journal of Asian
Natural Products Research, 14:2, 165-170
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Journal of Asian Natural Products Research
Vol. 14, No. 2, February 2012, 165–170
Smilasides M and N, two new phenylpropanoid glycosides from
Smilax riparia
Ting-Ting Sun, Dian-Wen Zhang, Yan Han, Fang-Yan Dong and Wei Wang*
Institute of Phytochemistry, Jilin Academy of Chinese Medicine Sciences, Changchun 130012, China
(Received 11 September 2011; final version received 14 November 2011)
Two new phenylpropanoid glycosides, smilasides M and N, together with the known
compound 20,60-diacetyl-3,6-diferuloylsucrose, were isolated and characterized from
the roots and rhizomes of Smilax riparia A. DC. The structures of the new compounds
were elucidated as 20,60-diacetyl-3-Z-feruloyl-6-feruloylsucrose (1) and 20,60-diacetyl-
3-feruloyl-6-Z-feruloylsucrose (2) on the basis of extensive analysis of HR-ESI-MS,
UV, IR, and 1D and 2D NMR spectroscopic data.
Keywords: Smilax riparia; Liliaceae; phenylpropanoid glycosides; smilaside M;
smilaside N
1. Introduction
lumbago of renal asthenia, traumatic
injury, asthenia edema, and bronchial
dilation agents [22]. Although several
constituents, including four steroidal
saponins, four flavonoids, a phenylpro-
panoid glycoside, and an aromatic
compound, were isolated and identified
from the roots and rhizomes of S. riparia
previously [23,24], a systematic phyto-
chemical investigation has not been
pursued. As a part of our ongoing search
for bioactive secondary metabolites from
medicinal plants growing in the Chang-
bai Mountain, Jilin Province of China,
we investigated the constituents of the
roots and rhizomes of S. riparia.
Fractionation of the ethanol extract led
to the isolation of two new phenylpro-
panoid glycosides, namely smilasides M
and N (1 and 2), along with the known
compound 20,60-diacetyl-3,6-diferuloylsu-
crose (3) (Figure 1). We report herein on
the isolation and structural elucidation of
The genus Smilax belongs to the family
Liliaceae and comprises about 300
species, which distribute widely in the
tropical and temperate regions of East
Asia and South and North America [1].
The extracts of many plants from this
genus have been reported to exhibit anti-
hyperuricemic and nephroprotective [2],
anticonvulsant and neurotoxic [3], anti-
proliferative and pro-apoptotic [4], anti-
inflammatory and anti-nociceptive [5],
hypoglycemic [6], antioxidant [7,8], and
immunomodulatory activities [9]. Phyto-
chemical investigations on the genus
Smilax have revealed the occurrence of
steroidal saponins [10–12], phenylpropa-
noid glycosides [13–15], flavonoids
[16–18], and phenolic compounds [19–
21]. Smilax riparia A. DC. is a climbing
herbaceous vine distributed in the south
and midland of China. Its roots and
rhizomes have been used as a folklore
medicine for the treatment of bronchitis,
1
and 2 using spectroscopic data
*Corresponding author. Email: w.w.wangwei@263.net
ISSN 1028-6020 print/ISSN 1477-2213 online
q 2012 Taylor & Francis
http://dx.doi.org/10.1080/10286020.2011.641536
http://www.tandfonline.com

166
T.-T. Sun et al.
H-2000). The coupling constants J ¼ 12.8 Hz
O
of the proton signals at d 5.92/6.94 and
J ¼ 15.8 Hz of the proton signals at d
6.38/7.65 suggested the presence of a pair
of cis-olefinic protons and a pair of trans-
olefinic protons. The above 1H NMR data,
along with two methoxy groups at the
aromatic moieties as determined from the
HMBC spectrum, indicated the presence of
one Z-feruloyl and one feruloyl units in 1.
The 13C NMR chemical shifts attributable
to 18 sp2 carbons (Table 1) were in good
agreement with those of one Z-feruloyl and
one feruloyl moieties. In its 1H NMR
spectrum, there were signals for two acetyl
groups at d 2.04 (s) and 2.05 (s). The 13C
NMR spectrum also displayed resonances
due to two acetyl groups. In addition,
signals for eight oxygenated methines at d
5.54 (d, J ¼ 8.6 Hz, H-3), 4.45 (t,
J ¼ 8.6 Hz, H-4), 4.10 (m, H-5), 5.65 (d,
J ¼ 3.8 Hz, H-10), 4.57 (d, J ¼ 9.8, 3.8 Hz,
H-20), 3.79 (t, J ¼ 9.8 Hz, H-30), 3.32 (t,
J ¼ 9.8 Hz, H-40), and 4.18 (m, H-50), three
oxygenated methylenes at d 3.44 (d,
J ¼ 11.7 Hz, H-1a) and 3.63 (d,
J ¼ 11.7 Hz, H-1b), 4.47 (m, H-6a) and
4.50 (m, H-6b), and 4.16 (m, H-60a) and
O
6'
4'
OH
5'
O
O
1
HO
O
5
1'
HO
2'
O
HO
3'
3
O
2
6
4
OR2
OR1
OCH3
OH
O
X =
OCH3
OH
O
X' =
R1
R2
X'
X
1
2
3
X
X'
X'
X'
Figure 1. Chemical structures of compounds
1–3.
analysis, including 1D and 2D NMR
techniques.
1
4.43 (m, H-60b) were observed in the H
NMR spectrum. A characteristic anomeric
signal at d 5.65 with a smaller coupling
2. Results and discussion
Compound 1 was obtained as a yellowish
gum with
constant J ¼ 3.8 Hz, together with the 13
C
a
molecular formula of
NMR spectrum showing 12 oxygenated
carbon resonances containing two anome-
ric carbons at d 90.1 and 105.2, suggested
that 1 possessed a disaccharide moiety.
C36H42O19 on the basis of the quasi-
molecular ion at m/z 779.2394 [M þ H]þ
in the HR-ESI-MS. The IR and UV spectra
displayed absorption bands for the
hydroxyl and a,b-unsatuated aromatic
ester groups. The 1H NMR spectrum
(Table 1) showed two pairs of olefinic
protons at d 5.92 (d, J ¼ 12.8 Hz, H-800) and
6.94 (d, J ¼ 12.8 Hz, H-700), and 6.38 (d,
J ¼ 15.8 Hz, H-8000) and 7.65 (d,
J ¼ 15.8 Hz, H-7000), and two aromatic
moieties with ABX coupling patterns at d
6.78 (d, J ¼ 8.2 Hz, H-500), 7.19 (dd,
J ¼ 8.2, 1.6 Hz, H-600), and 7.80 (br s, H-
200) and at d 6.82 (d, J ¼ 8.2 Hz, H-5000), 7.10
(br d, J ¼ 8.2 Hz, H-6000), and 7.21 (br s,
1
Detailed analysis of the H and 13C NMR
spectroscopic data of 1 with the aid of 2D
NMR analyses indicated that the two
sugars comprise b-D-fructose and a-D-
glucose moieties connected through a 2!1
linkages. Thus, 1 should be a phenylpro-
panoid sucroside. On further inspection of
the HMBC spectrum, not only the Z-fer-
uloyl and feruloyl moieties at C-3 and C-6
in fructose, but also each acetyl group at
C-20 and C-60 of glucose could be assigned
unambiguously, due to the correlations
observed between H-3, H-6, H-20, and H-60,

Journal of Asian Natural Products Research
167
Table 1. 1H NMR (500 MHz) and 13C NMR (125 MHz) spectroscopic data for compounds 1 and 2
in CD3OD.
1
2
No.
dH
dC
dH
dC
b-D-Fru
1
3.44 (d, J ¼ 11.7 Hz)
3.63 (d, J ¼ 11.7 Hz)
64.9 (t)
3.42 (d, J ¼ 12.0 Hz)
3.60 (d, J ¼ 12.0 Hz)
64.8 (t)
2
3
4
5
6
105.2 (s)
78.1 (d)
73.7 (d)
81.1 (d)
65.0 (t)
105.4 (s)
78.4 (d)
74.4 (d)
81.2 (d)
65.3 (t)
5.54 (d, J ¼ 8.6 Hz)
4.45 (t, J ¼ 8.6 Hz)
4.10 (m)
4.47 (m)
4.50 (m)
5.54 (d, J ¼ 8.2 Hz)
4.43 (t, J ¼ 8.5 Hz)
4.11 (m)
4.44 (m)
4.48 (m)
a-D-Glc
10
20
30
40
50
60
5.65 (d, J ¼ 3.8 Hz)
4.57 (d, J ¼ 9.8, 3.8 Hz)
3.79 (t, J ¼ 9.8 Hz)
3.32 (t, J ¼ 9.8 Hz)
4.18 (m)
90.1 (d)
74.4 (d)
72.0 (d)
71.8 (d)
71.9 (d)
65.1 (t)
5.57 (d, J ¼ 3.8 Hz)
4.59 (d, J ¼ 10.0, 3.8 Hz)
3.81 (t, J ¼ 10.0 Hz)
3.36 (t, J ¼ 10.0 Hz)
4.18 (m)
90.4 (d)
74.4 (d)
72.1 (d)
71.9 (d)
72.0 (d)
65.6 (t)
4.16 (m)
4.43 (m)
4.15 (m)
4.40 (m)
Feruloyl-3
100
200
127.9 (s)
115.2 (d)
148.4 (s)
149.9 (s)
115.8 (d)
127.1 (d)
146.9 (d)
115.5 (d)
167.4 (s)
56.5 (q)
126.9 (s)
112.0 (d)
148.0 (s)
149.5 (s)
115.6 (d)
124.5 (d)
148.0 (d)
114.6 (d)
168.9 (s)
56.5 (q)
7.80 (br s)
7.26 (br s)
300
400
500
6.78 (d, J ¼ 8.2 Hz)
6.81 (d, J ¼ 8.2 Hz)
600
7.19 (dd, J ¼ 8.2, 1.6 Hz)
6.94 (d, J ¼ 12.8 Hz)
5.92 (d, J ¼ 12.8 Hz)
7.12 (dd, J ¼ 8.2, 1.6 Hz)
7.71 (d, J ¼ 15.8 Hz)
6.45 (d, J ¼ 15.8 Hz)
700
800
900
OCH3
Feruloyl-6
1000
3.89 (s)
3.90 (s)
127.8 (s)
111.8 (d)
149.4 (s)
150.8 (s)
116.5 (d)
124.2 (d)
147.1 (d)
115.3 (d)
168.8 (s)
56.6 (q)
127.5 (s)
115.2 (d)
148.0 (s)
148.4 (s)
115.7 (d)
124.2 (d)
146.0 (d)
115.2 (d)
167.9 (s)
56.5 (q)
2000
7.21 (br s)
7.83 (br s)
3000
4000
5000
6.82 (d, J ¼ 8.2 Hz)
7.10 (br d, J ¼ 8.2 Hz)
7.65 (d, J ¼ 15.8 Hz)
6.38 (d, J ¼ 15.8 Hz)
6.77 (d, J ¼ 8.2 Hz)
6000
7.14 (dd, J ¼ 8.2, 1.9 Hz)
6.88 (d, J ¼ 12.8 Hz)
5.84 (d, J ¼ 12.8 Hz)
7000
8000
9000
OCH3
OAc-20
3.90 (s)
2.05 (s)
2.04 (s)
3.88 (s)
2.09 (s)
2.07 (s)
172.3 (s)
20.9 (q)
172.9 (s)
20.8 (q)
172.4 (s)
21.0 (q)
172.8 (s)
21.0 (q)
OAc-60
and the corresponding carbonyl carbons
of Z-ferulate, ferulate, and acetates
(Figure 2). From the above evidence, the
structure of 1 was established as 20,60-
diacetyl-3-Z-feruloyl-6-feruloylsucrose,
and named smilaside M.
Compound 2 showed a quasi-molecu-
lar ion at m/z 779.2402 by HR-ESI-MS,
which is consistent with the molecular
formula C36H42O19. The 1H and 13C NMR
spectra suggested that 2 possessed a
structure similar to 1, containing glucose

168
T.-T. Sun et al.
O
O
OH
O
HO
HO
O
HO
O
O
O
O
O
O
O
OCH3
OH
H3CO
HO
Figure 2. Key HMBC correlations of compound 1.
and fructose units, one Z-feruloyl and one
feruloyl moieties, and two acetyl groups.
Furthermore, by comparing the HMBC
spectrum of 2 with that of 1, the position of
feruloyl moiety was determined at C-3 of
fructose in 2 instead of C-6 in 1, due to the
long-range correlation between the ester
carbonyl carbon at d 168.9 of feruloyl
moiety and the H-3 at d 5.54 of fructose for
2, while that of position of Z-feruloyl
moiety was determined at C-6 of fructose
in 2 instead of C-3 in 1, due to the long-
range correlations between the ester
carbonyl carbon at d 167.9 of Z-feruloyl
moiety and H-6 at d 4.44 and 4.48 of
fructose for 2. Accordingly, the structure
of 2 was determined as 20,60-diacetyl-3-
feruloyl-6-Z-feruloylsucrose, and named
smilaside N.
spectrometer with absorption given in
cm21. Optical rotations were measured
by using a HORIBA SEPA-300 digital
polarimeter. NMR spectra were measured
on a Bruker AV-500 FT-NMR in CD3OD,
using visual CD3OD resonances (1H d
3.31, 13C d 49.0) for internal reference. All
chemical shifts (d) are given in ppm. HR-
ESI-MS and ESI-MS were obtained with a
Bruker microTOFQ mass spectrometer
(Bruker Daltonics, Bremen, Germany).
Column chromatography was obtained
with macroporous resin D101 (Haiguang
Chemical Ltd, Tianjin, China), silica gel
(200–300 mesh, Qingdao Marine Chemi-
cal Factory, Qingdao, China), RP-18
reversed-phase silica gel (S-50 mm,
YMC, Kyoto, Japan), and Sephardex LH-
20 (GE Healthcare, Uppsala, Sweden).
TLC analysis was carried out on pre-
coated TLC plates with silica gel 60 F254
and silica gel RP-18 60 F254 (Merck,
Darmstadt, Germany, 0.25 mm). Detection
was achieved by spraying with 10%
H2SO4 in MeOH followed by heating.
Preparative HPLC was carried out on a
Shimadzu LC-6AD pump connected with
a Shimadzu SPD-20A UV–vis detector (at
220 nm) and a SHODEX RI-102 detector,
using Shim Pak ODS column
(250 mm £ 21.2 mm, i.d., 5 mm, Shi-
madzu, Kyoto, Japan) and Kromasil silica
column (250 mm £ 10 mm, i.d., 5 mm,
The known compound 20,60-diacetyl-
3,6-diferuloylsucrose (3) was also isolated
and identified by comparison of their
spectral data with those reported in the
literature [25].
3. Experimental
3.1 General experimental procedures
UV spectra were measured with a
Shimadzu UV-2100 spectrometer in
methanol with absorption given in nm
and IR spectra were measured as KBr
pellets with
a Perkin-Elmer FT-IR

Journal of Asian Natural Products Research
169
Fluka BioChemika, Buchs, Switzerland),
respectively. All solvents used for chro-
matographic separations were distilled
before use.
compounds 1 (15.2 mg, tR ¼ 197 min), 2
(10.2 mg, tR ¼ 252 min), and 3 (40.4 mg,
tR ¼ 230 min).
3.3.1 Smilaside M (1)
25
3.2 Plant material
A yellowish gum; ½aꢀD þ 18.4 (c ¼ 0.56,
The roots and rhizomes of S. riparia were
collected from Changbai Mountain, Jilin
Province of China, in October 2007, and
were authenticated by Prof. Zhongkai Yan,
Jilin Academy of Chinese Medicine
Sciences, China. A voucher specimen
(SRNWC-2007-10) is deposited at the
Institute of Phytochemistry, Jilin Academy
of Chinese Medicine Sciences, China.
CH3OH); UV lmax (CH3OH): 322, 299
(sh), 233, 219; IR ymax (KBr): 3364, 2943,
2837, 1704, 1603, 1448, 1278, 1029 cm21
;
1H NMR (500 MHz, CD3OD) and 13C
NMR (125 MHz, CD3OD) spectroscopic
data see Table 1; HR-ESI-MS: m/z
779.2394
C36H43O19, 779.2399).
[M þ H]þ
(calcd
for
3.3.2 Smilaside N (2)
25
3.3 Extraction and isolation
A yellowish gum; ½aꢀD þ 10.5 (c ¼ 0.78,
CH3OH); UV lmax (CH3OH): 320, 299
(sh), 231, 217; IR ymax (KBr): 3365, 2945,
The air-dried and ground roots and
rhizomes (23.5 kg) of S. riparia were
extracted twice with 95% ethanol under
reflux for 2 h and the solvent was
evaporated under reduced pressure to
give a brown residue (1.85 kg). The
residue (1.8 kg) was diluted with distilled
water and subjected to D101 macroporous
resin column chromatography and eluted
with H2O and 30% and 70% ethanol,
successively. The fraction eluted with 70%
ethanol (200 g) was suspended in water
and successively partitioned with chloro-
form, ethyl acetate, and n-butanol.
2837, 1700, 1598, 1450, 1278, 1030 cm21
;
1H NMR (500 MHz, CD3OD) and 13C
NMR (125 MHz, CD3OD) spectroscopic
data see Table 1; HR-ESI-MS: m/z
779.2402
C36H43O19, 779.2399).
[M þ H]þ
(calcd
for
3.3.3 Alkaline hydrolysis of 1 and 2
Compounds 1 (5.2 mg) and 2 (4.8 mg)
were hydrolyzed with 5% KOH/MeOH
(3 ml) at room temperature for 20 min.
The reaction mixture was neutralized with
2 M HCl and filtered. The filtrate was
concentrated under reduced pressure to
give a residue that was chromatographed
over a Sephardex LH-20 column (MeOH)
and preparative HPLC (silica gel column:
250 mm £ 10 mm, i.d., 5 mm; flow rate:
2 ml/min) using CHCl3 –MeOH–H2O
(90:70:15) as the mobile phase to yield
sucrose (1.5 mg from 1 and 1.4 mg from
2, tR ¼ 17.6 min). The sucrose was
detected by co-injection of an authentic
sample on preparative HPLC in the same
manner described above, giving a single
peak.
The EtOAc-soluble fraction (15 g) was
chromatographed over a silica gel column
(8 £ 60 cm, 1.0 kg) eluting with CHCl3–
MeOH (49:1, 19:1, 9:1, and 1:1) and
separated into nine fractions (Fractions I–
IX) on the basis of TLC analyses. Fraction III
(2 g) was subjected to RP-18 reversed-phase
silica gel column (3 £ 25, 100 g) chroma-
tography witha MeOH–H2O (50:50) solvent
system to afford six subfractions (Subfrac-
tions III-1–III-6). Subfraction III-3 (166 mg)
was isolated by preparative HPLC (RP-18
column: 250 mm £ 21.2mm, i.d., 5 mm;
flow rate: 2 ml/min) using CH3CN–H2O
(28:72) as the mobile phase to yield

170
T.-T. Sun et al.
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Acknowledgement
This project was financially supported by the
National Science and Technology Program of
China (2007BAI38B05).
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