Grevillosides A-F: Glucosides of 5-alkylresorcinol derivatives from leaves of Grevillea robusta

Article abstract of DOI:10.1016/j.phytochem.2008.08.008

From a MeOH extract of leaves of Grevillea robusta, seven compounds (1-7) were isolated. One known compound (7) was identified with a benzyl glucoside, icariside F₂. The structures of the six of these, named grevillosides A-F (1-6), were elucidated on detailed inspection of one- and two-dimensional NMR spectroscopic data as glucosides of 5-alkylresorcinols.

Full text of DOI:10.1016/j.phytochem.2008.08.008

Phytochemistry 69 (2008) 2749–2752
Contents lists available at ScienceDirect
Phytochemistry
journal homepage: www.elsevier.com/locate/phytochem
Grevillosides A–F: Glucosides of 5-alkylresorcinol derivatives from leaves of
Grevillea robusta
b
c
Yukiko Yamashita a, Katsuyoshi Matsunami a, Hideaki Otsuka a, , Takakazu Shinzato , Yoshio Takeda
*
a Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
b Subtropical Field Science Center, Faculty of Agriculture, University of the Ryukyus, 1 Sembaru, Nishihara-cho, Nakagami-gun, Okinawa 903-0213, Japan
c Faculty of Integrated Arts and Sciences, The University of Tokushima, 1 Minamijosanjima-cho, Tokushima 770-8502, Japan
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 12 March 2008
Received in revised form 24 June 2008
Available online 21 September 2008
From a MeOH extract of leaves of Grevillea robusta, seven compounds (1–7) were isolated. One known
compound (7) was identified with a benzyl glucoside, icariside F2. The structures of the six of these,
named grevillosides A–F (1–6), were elucidated on detailed inspection of one- and two-dimensional
NMR spectroscopic data as glucosides of 5-alkylresorcinols.
Ó 2008 Elsevier Ltd. All rights reserved.
Keywords:
Grevillea robusta
Proteaceae
5-Alkylresorcinol glucoside
Grevilloside
1. Introduction
2. Results and discussion
Most of the 1200 species of the 55 genera in Proteaceae grow in
Australia and South Africa, and only one species, Helicia cochinchin-
ensis, grows naturally in Japan. Phytochemical investigation of H.
Air-dried leaves of G. robusta were extracted with MeOH three
times and the concentrated MeOH extract was partitioned with
solvents of increasing polarity. The 1-BuOH-soluble fraction was
separated by means of various chromatographic procedures
including CC on a highly-porous synthetic resin (Diaion HP-20),
and then normal silica gel and reversed-phase (ODS) CC, droplet
counter-current chromatography (DCCC), and HPLC to afford seven
compounds (1–7). The details and yields are given in the Section 4.
The structure of a known benzyl glycoside (7) was identified as
icariside F2 by comparison with data, reported in the literature
(Miyase et al., 1988).
cochinchinensis led to the isolation of 5-O-b-D-glucopyranosides of
flavanones (Morimura et al., 2006). Grevillea robusta A. Cunn.,
belonging to Proteaceae, originates from subtropical areas of east-
ern Australia and has been planted in Japan. It is an evergreen tree
between 20 m and 35 m in height with dark green delicately
dented bipinnatifid leaves reminiscent of fronds. The leaves are
15–30 cm long with grey-white or rusty undersides. Phytochemi-
cal investigation of the same plant, collected in Egypt, has been re-
ported and several phenolic glucosides were isolated (Ahmed et al.,
2000). Cytotoxic 5-alkylresorcinol metabolites were also isolated
from the title plant (Chuang and Wu, 2007) and a MeOH extract
of its timber exhibited potent leishmanicidal activity (Takahashi
et al., 2004). 5-Alkylresorcinols (Kozubeck and Tyman, 1999) are
found in a mushroom, Merulius incarnatus (Jin and Zjawiony,
2006), a Malagasy Myrsinaceous plant, Oncostemon bojerianum
(Chaturvedula et al., 2002), Lysimachia japonica (Primulaceae)
(Arisawa et al., 1989), and some cereals (Ross et al., 2003; Chen
et al., 2004). The cytotoxicities of 5-alkylresorcinols have also been
discussed (Arisawa et al., 1989; Chaturvedula et al., 2002; Chuang
and Wu, 2007). In our continuing studies on Okinawan plants, the
chemical constituents of G. robusta, collected in Okinawa, were
investigated.
Grevilloside A (1), [
a]
ꢀ60.7, was isolated as an amorphous
D
powder and its elemental composition was determined to be
C17H24O8 from the observation of a quasi-molecular ion peak
([M+Na]) on HR-ESI-mass-spectrometry. The IR spectrum exhib-
ited absorption bands for hydroxyl groups (3396 cmꢀ1) and an aro-
matic ring (1614 cmꢀ1 and 1507 cmꢀ1), and the UV spectrum also
indicated the presence of an aromatic ring. In the 1H NMR spec-
trum, three aromatic protons were observed, which were coupled
to each other with coupling constants of 2 Hz. The 13C NMR
spectrum, together with the DEPT experiment results, indicated
the presence of three aromatic signals each with a proton and an-
other three each without a proton. Two of the aromatic resonances,
without a proton were highly deshielded, indicating that they
probably carried hydroxyl groups. The remaining signals in the
13C NMR spectrum consisted of six assignable to b-glucopyranose,
and one double bond, two methylenes and one oxymethylene. A
sequential 1H–1H COSY correlation from H2-11 (dH 3.59) to H2-7
* Corresponding author. Tel./fax: +81 82 257 5335.
E-mail address: hotsuka@hiroshima-u.ac.jp (H. Otsuka).
0031-9422/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved.
doi:10.1016/j.phytochem.2008.08.008

2750
Y. Yamashita et al. / Phytochemistry 69 (2008) 2749–2752
(dH 3.30–3.45) established the alkyl chain to be as shown in Fig. 1
(Fig. 2). The coupling constants (11 Hz) of two olefinic protons
indicated the geometry of the double bond to be of the cis form.
A HMBC correlation from H-10 (dH 4.84) to C-1 (dC 160.3) confirmed
that the b-glucopyranosyl moiety was on the phenolic hydroxyl
group and this was further supported by the difference NOE exper-
iment, in which irradiation of the anomeric proton caused signifi-
cant enhancement of two aromatic protons (dH 6.45 and 6.39)
(Fig. 2). HMBC correlations between H-2 (dH 6.39) and C-4 and C-
6 (dC 110.6 and 109.2), and H-7 (dH 3.30–3.45) and C-4 and C-6
established the structure, as shown in Fig. 1. The absolute configu-
ration of glucose was determined to be of the D-series on HPLC
analysis of the hydrolyzate of 1 using an optical rotation detector.
H
OH
HO
O
O
OH
OH
OH
Grevilloside B (2), [
a
]
D
ꢀ37.5, was isolated as an amorphous
powder and its elemental composition was determined to be
C17H26O8 by HR-ESI-MS. In the 13C NMR spectrum, the aromatic
substitution pattern was established to be the same as that of grev-
illoside A (1), and the HMBC spectrum also showed the same cor-
relation between the anomeric proton (dH 4.86) and the highly
deshielded carbon atom (dC 160.0). The alkyl chain consisted of
four methylenes and one oxymethylene. Thus, the structure of
grevilloside B (2) was elucidated to be a dihydro derivative of grev-
illoside A (1), as shown in Fig. 1.
HO
Fig. 2. Diagnostic two-dimensional NMR correlations (bold line: COSY, and plain
curves: HMBC from H to C) and the results of the difference NOE experiments
(dashed curves) for 1.
the structures of grevilloside D (4) and grevilloside E (5) were elu-
cidated to be one methylene less forms of grevillosides B (2) and C
(3), respectively.
Grevilloside C (3), [
a]
ꢀ49.6, was also isolated as an amor-
D
Grevilloside F (6), [
a]
ꢀ58.9, was isolated as an amorphous
D
phous powder and its elemental composition was determined by
HR-ESI-MS to be C17H24O9, which is two hydrogen atom less and
one oxygen atom more than in the case of grevilloside B (2). In
the IR spectrum, absorption for the carboxyl moiety was observed
at 1713 cmꢀ1. The 13C NMR spectrum showed that 3 was an anal-
ogous compound to 2, and the oxymethylene signal observed in
that of 2 was replaced by a carbonyl carbon signal. Therefore, grev-
illoside C (3) was elucidated to be the 11-carboxylic acid derivative
of grevilloside B (2).
powder and its elemental composition was determined to be
C15H18O9 by HR-ESI-MS. The NMR spectra indicated that the aro-
matic moiety was the same as that of the aforementioned com-
pounds. However, the side chain consisted of a double bond (dH
6.39 and 7.54) and a carboxylic acid moiety. The geometry of the
double bond was determined to be trans from the coupling con-
stants (J = 16 Hz) of the olefinic protons in the 1H NMR spectrum.
Therefore, the structure of grevilloside F (6) was elucidated to be
as shown in Fig. 1.
Grevilloside D (4), [
a
]
D ꢀ27.6, and grevilloside E (5), [ D ꢀ42.1,
a
]
were isolated as amorphous powders, and their elemental compo-
sitions were determined to be C16H24O8 and C16H22O9, respectively,
by HR-ESI-MS. The NMR spectroscopic data showed that these
were analogous compounds to grevillosides B (2) and C (3), respec-
tively, and together with the data obtained on mass-spectrometry,
3. Conclusion
From leaves of G. robusta, six new 5-alkylresorcinol glucosides
were isolated. As far as we know, this is the first example of the
isolation of glycosidic forms of these alkylresorcinol. Biological
evaluation of the isolated compounds is in progress.
Glc('1)O
1
R
4. Experimental
11
2
R
1
5
4.1. General experimental procedures
OH
7
7
11
HO
Optical rotations were measured on a JASCO P-1030 polarime-
ter. IR and UV spectra were measured on Horiba FT-710 and JASCO
V-520 UV/VIS spectrophotometers, respectively. 1H and 13C NMR
CH2(CH2)3CH2OH
2
3
7
11
spectra were taken on
a JEOL JNM a-400 spectrometer at
CH2(CH2)3COOH
400 MHz and 100 MHz, respectively, with tetramethylsilane as
an internal standard. Positive-ion HR-MS was performed with an
Applied Biosystem QSTAR XL system ESI (Nano Spray)-TOF-MS.
A highly-porous synthetic resin (Diaion HP-20) was purchased
from Mitsubishi Kagaku (Tokyo, Japan). Silica gel CC and re-
versed-phase [octadecyl silica gel (ODS)] open CC were performed
7
10
CH2(CH2)2CH2OH
4
5
10
7
CH2(CH2)2COOH
on silica gel 60 (Merck, Darmstadt, Germany) and Cosmosil 75C18
-
OPN (Nacalai Tesque, Kyoto, Japan) [ = 50 mm, L = 25 cm, linear
U
9
6
COOH
gradient: MeOH–H2O (1:9, 1 L) ? (1:1, 1 L), fractions of 10 g being
collected], respectively. The droplet counter-current chromatogra-
phy (DCCC) (Tokyo Rikakikai, Tokyo, Japan) was equipped with 500
7
glass columns (
U = 2 mm, L = 40 cm), and the lower and upper lay-
OGlc(6)Api
Glc: β-D-glucopyranosyl
Api:β -D-apiofuranosyl
ers of a solvent mixture of CHCl3–MeOH–H2O-n-PrOH (9:12:8:2)
were used as the stationary and mobile phases, respectively.
Five-gram fractions were collected and numbered according to
their order of elution with the mobile phase. HPLC was performed
7
Fig. 1. Structures.

Y. Yamashita et al. / Phytochemistry 69 (2008) 2749–2752
2751
on an ODS column (Inertsil; GL Science, Tokyo, Japan;
U
= 6 mm,
nm (loge
): 277 (3.21), 228 (3.55); 1H NMR (CD3OD, 400 MHz) d:
L = 25 cm), and the eluate was monitored with a UV detector at
254 nm and a refractive index monitor.
6.45 (1H, dd, J = 2, 2 Hz, H-6), 6.39 (1H, dd, J = 2, 2 Hz, H-2), 6.33
(1H, dd, J = 2, 2 Hz, H-4), 5.62 (1H, dtt, J = 11, 7, 1 Hz, H-8), 5.52
(1H, dtt, J = 11, 7, 2 Hz, H-9), 4.84 (1H, d, J = 8 Hz, H-10), 3.89 (1H,
dd, J = 12, 2 Hz, H-60a), 3.70 (1H, dd, J = 12, 5 Hz, H-60b), 3.59 (2H,
t, J = 7 Hz, H-11), 3.43 (1H, dd, J = 9, 8 Hz, H-20), 3.40 (1H, dd,
J = 9, 9 Hz, H-40), 3.39 (1H, dd, J = 9, 9 Hz, H-30), 3.43–3.47 (1H, m,
H-50), 3.30–3.45 (2H, m, H2-7), 2.38 (2H, ttd, J = 7, 7, 1 Hz, H2-10);
13C NMR (CD3OD, 100 MHz): Table 1; HR-ESI-TOF-MS (positive-
ion mode) m/z: 379.1361 [M+Na]+ (calc. for C17H24O8Na,
379.1363).
4.2. Plant material
Leaves of G. robusta A. Cunn. (Proteaceae) were collected in
Okinawa, Japan, in August 2005, and a voucher specimen was depos-
ited in the Herbarium of Pharmaceutical Sciences, Graduate School
of Biomedical Sciences, Hiroshima University (05-GR-Okinawa-
0629).
4.3. Extraction and isolation
4.4.2. Grevilloside B (2)
Amorphous powder; ½a D31
ꢁ
ꢀ37.5 (c = 1.42, MeOH); IR
mmax (film)
Dried leaves of G. robusta (6.35 kg) were extracted three times
with MeOH (30 L) at 25 °C for one week and then concentrated
to 3 L in vacuo. The extract was washed with n-hexane (3 L,
32.6 g) and then the MeOH layer was concentrated to a gummy
mass. The latter was suspended in H2O (3 L) and then extracted
with EtOAc (3 L) to give an EtOAc-soluble fraction (160 g). The
cmꢀ1: 3395, 2929, 1595, 1508, 1458, 1172, 1074; UV kmax (MeOH)
nm (loge
): 271 (3.13), 226 (3.43); 1H NMR (CD3OD, 400 MHz) d:
6.44 (1H, dd, J = 2, 2 Hz, H-6), 6.40 (1H, dd, J = 2, 2 Hz, H-2), 6.33
(1H, dd, J = 2, 2 Hz, H-4), 4.86 (1H, d, J = 8 Hz, H-10), 3.90 (1H, dd,
J = 12, 2 Hz, H-60a), 3.71 (1H, dd, J = 12, 5 Hz, H-60b), 3.54 (2H, t,
J = 8 Hz, H-11), 3.46 (1H, dd, J = 9, 8 Hz, H-20), 3.44-3.48 (2H, m,
H-20 and 50), 3.42 (1H, dd, J = 9, 9 Hz, H-40), 2.51 (2H, t, J = 7 Hz,
H2-7), 1.61 (2H, m, H2-8), 1.55 (2H, m, H2-10), 1.37 (2H, m, H2-9);
13C NMR (CD3OD, 100 MHz): Table 1; HR-ESI-TOF-MS (positive-
ion mode) m/z: 381.1523 [M+Na]+ (calc. for C17H26O8Na,
381.1519).
aqueous-layer was extracted with 1-BuOH (3 L) to give
a
1-BuOH-soluble fraction (405 g), and the remaining aqueous-layer
was concentrated to furnish a water-soluble fraction (475 g).
A portion (237 g) of the 1-BuOH-soluble fraction was applied to
a Diaion HP-20 column (U = 75 mm, L = 50 cm) using H2O–MeOH
(4:1, 8 L), (2:3, 8 L), (3:2, 8 L), and (1:4, 8 L), and MeOH (6 L), 1 l
fractions being collected. The residue (19.9 g in fractions 4–6) of
the MeOH–H2O (1:4, v/v) eluent was subjected to silica gel
(450 g) CC, with elution with CHCl3 (3 L) and CHCl3–MeOH
[(49:1, 3 L), (24:1, 3 L), (23:2, 3 L), (9:1, 3 L), (7:1, 3 L), (17:3, 3 L),
(4:1, 3 L), (3:1, 3 L), and (3:2, 3 L)], 500 mL fractions being col-
lected. Combined fractions 46–52 (1.20 g) of the 20–25% MeOH
in H2O (v/v) eluate were separated by ODS open CC to give 6
(187 mg).
4.4.3. Grevilloside C (3)
Amorphous powder; ½a D31
ꢁ
ꢀ49.6 (c = 0.75, MeOH); IR
mmax (film)
cmꢀ1: 3388, 2932, 1713, 1597, 1508, 1457, 1173, 1075; UV kmax
(MeOH) nm (loge
): 275 (3.27), 225 (3.52); 1H NMR (CD3OD,
400 MHz) d: 6.44 (1H, dd, J = 2, 2 Hz, H-6), 6.39 (1H, dd, J = 2,
2 Hz, H-2), 6.31 (1H, dd, J = 2, 2 Hz, H-4), 4.85 (1H, d, J = 8 Hz, H-
10), 3.89 (1H, dd, J = 12, 2 Hz, H-60a), 3.70 (1H, dd, J = 12, 5 Hz, H-
60b), 3.43–3.48 (1H, m, H-50), 3.44 (1H, dd, J = 9, 8 Hz, H-20), 3.42
(1H, dd, J = 9, 9 Hz, H-30), 3.40 (1H, dd, J = 9, 9 Hz, H-40), 2.52 (2H,
m, H2-7), 2.30 (2H, m, H2-10), 1.60–1.64 (4H, m, H2-8 and H2-9);
13C NMR (CD3OD, 100 MHz): Table 1; HR-ESI-TOF-MS (positive-
ion mode) m/z: 395.1318 [M+Na]+ (calc. for C17H24O9Na,
395.1312).
The residue (45.1 g) of fractions 7–12, obtained on Diaion HP-20
CC, was subjected to silica gel (450 g) CC, with elution with CHCl3
(4.5 L) and CHCl3–MeOH [(49:1, 4.5 L), (24:1, 4.5 L), (23:2, 4.5 L),
(9:1, 4.5 L), (7:1, 4.5 L), (17:3, 4.5 L), (4:1, 4.5 L), (3:1, 4.5 L), and
(3:2, 4.5 L)], 500 mL fractions being collected. An aliquot (1.76 g)
of combined fractions 61–66 (2.61 g) of the 12.5–15% MeOH in
H2O (v/v) eluate was separated by ODS open CC gave two residues
in fractions 88–99 (204 mg) and fractions 100–119 (548 mg), fol-
lowed by DCCC. The residue (27.2 mg) of fractions 20–24 from
DCCC was purified by preparative HPLC (MeOH–H2O, 1:3) to give
1 (7.9 mg) from the peak at 15 min. From the residue (38.5 mg)
of fractions 25–28 from DCCC, a further amount of 1 (3.7 mg)
was obtained by the same method. The residue (548 mg) of frac-
tions 100–119, obtained on ODS open CC, was separated by DCCC
(152 mg in fractions 25–35), and then purified by preparative HPLC
(MeOH–H2O, 1:4) to give 7 (27.0 mg) and 2 (21.3 mg) from the
peaks at 35 min and 43 min, respectively. An aliquot (1.85 g) of
the residue (2.01 g) of fractions 67–73, obtained on silica gel CC,
was subjected to ODS open CC gave two fractions, 273 mg in frac-
tions 70–88 and 485 mg in fractions 100–115. The former was the
separated by DCCC to afford 130 mg of the residue of fractions 12–
18, which was then purified by repeated HPLC (MeOH–H2O, 1:4) to
furnish 4 (1.9 mg) from the peak at 13 min. From the latter, 3
(175 mg) was isolated by DCCC from fractions 28–35. The residue
(3.85 g) of fractions 74–87, obtained on silica gel CC, was subjected
to ODS open CC to give 5 (41.7 mg) in fractions 70–88.
4.4.4. Grevilloside D (4)
Amorphous powder; ½a D25
ꢁ
ꢀ27.6 (c = 0.13, MeOH); IR
mmax (film)
cmꢀ1: 3366, 2923, 1596, 1508, 1456, 1299, 1171, 1073; UV kmax
(MeOH) nm (loge
): 223 (4.01), 273 (3.47); 1H NMR (CD3OD,
400 MHz) d: 6.44 (1H, dd, J = 2, 2 Hz, H-6), 6.38 (1H, dd, J = 2,
2 Hz, H-2), 6.32 (1H, dd, J = 2, 2 Hz, H-4), 4.85 (1H, d, J = 8 Hz, H-
Table 1
13C NMR spectroscopic data for grevillosides A–F (1–6) (100 MHz, CD3OD)
1
2
3
4
5
6
1
2
3
4
5
6
7
160.3
102.8
159.5
110.6
144.7
109.2
34.6
160.0
102.5
159.2
110.7
146.3
109.3
36.9
160.2
102.7
159.4
110.7
145.9
109.2
36.6
160.2
102.7
159.4
110.7
146.2
109.3
36.8
160.2
102.8
159.4
110.7
145.3
109.3
36.2
160.6
107.4
160.0
110.1
137.8
108.9
146.3
119.7
170.3
8
9
10
11
131.3
127.7
31.8
32.1
26.5
33.4
63.0
31.7
28.6
27.6
25.7
33.2
34.4
34.8
62.9
177.6
62.8
177.6
10
20
30
40
50
60
102.3
75.0
78.2
71.5
78.1
62.6
102.2
74.9
78.0
71.4
78.0
62.5
102.3
75.0
78.1
71.5
78.1
62.5
102.3
75.0
78.2
71.5
78.2
62.7
102.3
75.0
78.1
71.5
78.1
62.6
102.4
75.0
78.3
71.5
78.1
62.6
4.4. Characterization data
4.4.1. Grevilloside A (1)
Amorphous powder; ½a D31
ꢁ
ꢀ60.7 (c = 0.53, MeOH); IR
mmax (film)
cmꢀ1: 3396, 2924, 1614, 1507, 1455, 1171, 1075; UV kmax (MeOH)

2752
Y. Yamashita et al. / Phytochemistry 69 (2008) 2749–2752
10), 3.89 (1H, dd, J = 12, 2 Hz, H-60a), 3.70 (1H, dd, J = 12, 5 Hz, H-
60b), 3.55 (2H, t, J = 7 Hz, H-11), 3.35–3.43 (4H, m, H-20, 30, 40 and
50), 2.53 (2H, t, J = 7 Hz, H2-7), 1.65 (2H, quintetd, J = 7, 2 Hz, H2-
8), 1.54 (2H, quintetd, J = 7, 2 Hz, H2-9); 13C NMR (CD3OD,
100 MHz): Table 1; HR-ESI-TOF-MS (positive-ion mode) m/z:
379.1365 [M+Na]+ (calc. for C16H24O8Na, 367.1363).
(1–6) gave the peak for
14.2 min (positive optical rotation sign). Peaks were identified by
co-chromatography with authentic D-glucose.
D-glucose at the retention time of
Acknowledgements
The authors are grateful for access to the superconducting NMR
instrument and ESI-TOF-MS at the Analytical Center of Molecular
Medicine and the Analysis Center of Life Science, respectively, of
the Hiroshima University Faculty of Medicine. This work was sup-
ported in part by Grants-in-Aid from the Ministry of Education,
Culture, Sports, Science and Technology of Japan, the Japan Society
for the Promotion of Science, and the Ministry of Health, Labour
and Welfare. Thanks are also due to the Astellas Foundation for
Research on Medicinal Resources and the Takeda Science
Foundation for the financial support.
4.4.5. Grevilloside E (5)
Amorphous powder; ½a D31
ꢁ
ꢀ42.1 (c = 0.81, MeOH); IR
mmax (film)
cmꢀ1: 3395, 2930, 1700, 1648, 1600, 1509, 1437, 1170, 1074; UV
kmax (MeOH) nm (loge
): 278 (3.41), 228 (3.55); 1H NMR (CD3OD,
400 MHz) d: 6.45 (1H, dd, J = 2, 2 Hz, H-6), 6.40 (1H, dd, J = 2,
2 Hz, H-2), 6.32 (1H, dd, J = 2, 2 Hz, H-4), 4.86 (1H, d, J = 8 Hz, H-
10), 3.89 (1H, dd, J = 12, 2 Hz, H-60a), 3.71 (1H, dd, J = 12, 5 Hz, H-
60b), 3.45 (1H, dd, J = 9, 8 Hz, H-20), 3.44–3.48 (1H, m, H-50), 3.44
(1H, dd, J = 9, 9 Hz, H-30), 3.42 (1H, dd, J = 9, 9 Hz, H-40), 2.54 (2H,
t, J = 7 Hz, H2-7), 2.28 (2H, t, J = 8 Hz, H2-9), 1.87 (2H, quintet,
J = 8 Hz, H2-8); 13C NMR (CD3OD, 100 MHz): Table 1; HR-ESI-
TOF-MS (positive-ion mode) m/z: 381.1160 [M+Na]+ (calc. for
C16H22O9Na, 379.1156).
References
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2000. Phenolic constituents from Grevillea robusta. Phytochemistry 53, 149–
154.
4.4.6. Grevilloside F (6)
Arisawa, M., Ohmura, K., Kobayashi, A., Morita, N., 1989.
A cytotoxic
Amorphous powder; ½a D27
ꢁ
ꢀ58.9 (c = 0.52, MeOH); IR
mmax (film)
constituent of Lysimachia japonica Thunb. (Primulaceae) and the
structure–activity relationships of related compounds. Chem. Pharm. Bull.
37, 2431–2434.
cmꢀ1: 3367, 2931, 1637, 1593, 1508, 1451, 1396, 1333, 1276, 1175,
1074; UV kmax (MeOH) nm (loge
): 277 (4.00), 222 (4.20); 1H NMR
Chaturvedula, V.S.P., Schilling, J.K., Miller, J.S., Andriantsiferana, R., Rasamison, V.E.,
Kingston, G.I., 2002. New cytotoxic bis 5-alkylresorcinol derivatives from the
leaves of Oncostemon bojerianum from the Madagascar rain forest. J. Nat. Prod.
65, 1627–1632.
Chen, Y., Ross, A.B., Aman, P., Kamal-Eldin, A., 2004. Alkylresorcinols as markers of
whole grain wheat and rye in cereal products. J. Agric. Food Chem. 52, 8242–
8246.
Chuang, T.-H., Wu, P.-L., 2007. Cytotoxic 5-alkylresorcinol metabolites from the
leaves of Grevillea robusta. J. Nat. Prod. 70, 319–323.
Jin, W., Zjawiony, J.K., 2006. 5-Alkylresorcinol from Merulius incanatus. J. Nat. Prod.
69, 704–706.
(CD3OD, 400 MHz) d: 7.54 (1H, d, J = 16 Hz, H-7), 6.84 (1H, dd, J = 2,
2 Hz, H-6), 6.68 (1H, dd, J = 2, 2 Hz, H-2), 6.62 (1H, dd, J = 2, 2 Hz, H-
2), 6.39 (1H, d, J = 16 Hz, H-8), 4.84 (1H, d, J = 8 Hz, H-10), 3.91 (1H,
dd, J = 12, 2 Hz, H-60a), 3.71 (1H, dd, J = 12, 5 Hz, H-60b), 3.44–3.48
(3H, m, H-20, 40 and 50), 3.41 (1H, dd, J = 9, 9 Hz, H-30); 13C NMR
(CD3OD, 100 MHz): Table 1; HR-ESI-TOF-MS (positive-ion mode)
m/z: 365.0847 [M+Na]+ (calc. for C15H18O9Na, 365.0843).
4.4.7. Known compound isolated
Icariside F2 (7), Amorphous powder,
MeOH).
Kozubeck, A., Tyman, J.H., 1999. Resorcinolic lipids, the natural non-isoprenoid
phenolic amphiphiles and their biological activity. Chem. Rev. 99, 1–26.
Miyase, T., Ueno, A., Takizawa, N., Kobayashi, H., Oguchi, H., 1988. Studies on the
glycosides of Epimedium grandiflorum Morr. var. thunbergianun (Miq.) Nakai. III.
Chem. Pharm. Bull. 36, 2475–2484.
½
a 2D9
ꢁ
ꢀ80.5 (c = 1.80,
Morimura, K., Gatayama, A., Tsukimata, R., Matsunami, K., Otsuka, H., Hirata, H.,
Shinzato, T., Aramoto, M., Takeda, Y., 2006. 5-O-Glucosylfalavanones from
leaves of Helicia cochinchinenesis. Phytochemistry 67, 2681–2685.
Ross, A.B., Shephered, M.J., Schüpphaus, M., Sinclair, V., Alfaro, B., Kamal-Eldin, A.,
Aman, P., 2003. Alkylresorcinols in cereals and cereal products. J. Agric. Food
Chem. 51, 4111–4118.
Takahashi, M., Fuchino, H., Satake, M., Agatsuma, Y., Sekita, S., 2004. In vitro
screening of leishmanicidal activity in Myanmar timber extracts. Biol. Pharm.
Bull. 27, 921–925.
4.4.8. Analyses of the sugar moiety
About 500 g each of grevillosides A-F (1–6) was hydrolyzed
l
with 1 N HCl (0.1 mL) at 100 °C for 2 h. The reaction mixtures were
partitioned with an equal amount of EtOAc (0.1 mL), and the
aqueous layers were analyzed with a chiral detector (JASCO
OR-2090plus) on an amino column [Asahipak NH2P-50 4E,
CH3CN–H2O (4:1), 1 ml/min]. Hydrolyzates of grevillosides A-F