PHYTOCHEMICAL ANALYSIS
Phytochem. Anal. 14, 48–53 (2003)
Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/pca.686
Guaiacylglycerol-7'-O-methyl 8'-vanillic Acid
Ether and Related Compounds from
Boreava orientalis
Akiyo Sakushima,1* Kosei Ohno,1 Takashi Maoka,2 Maksut Coskun,3 Aysegul Guvenc,3
Ceyda Sibel Erdurak,3 Ayse Mine Ozkan,3 Koh-ichi Seki1 and Kazue Ohkura1
1
Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto, Japan
3
Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmacy, University of Ankara, Ankara, Turkey
2
The threo and erythro forms of guaiacylglycerol-7'-O-methyl 8'-vanillic acid ethers, threo and erythro
guaiacylglycerol 8'-vanillin ethers, and threo guaiacylglycerol 8'-(4-hydroxymethyl-2-methoxyphenyl) ether
have been isolated from fruits of Boreava orientalis. Structural determinations were made on the basis of UV,
MS, 1H- and 13C-NMR spectral data, including two-dimensional shift correlation. The relative configurations
were assigned on the basis of 1H-NMR chemical shifts. Copyright # 2003 John Wiley & Sons, Ltd.
Keywords: Lignan; threo and erythro guaiacylglycerol-7'-O-methyl 8'-vanillic acid ethers; threo and erythro
guaiacylglycerol 8'-vanillin ethers; threo guaiacylglycerol 8'-(4-hydroxymethyl-2-methoxyphenyl) ether; guaiacylglycerol
ether; Boreava orientalis; Cruciferae.
INTRODUCTION
The fruits of Boreava orientalis (Cruciferae), a weed
which is widely distributed in Turkey, are used in
traditional medicine for the treatment of coughs and skin
disease (Tanker and Yenen, 1978; Tanker et al., 1983).
Some of the phenolic compounds present in this plant
exhibit important pharmacological and biological activities. In particular, derivatives of pyrocatechuic acid and
sinapic acid have been identified as potentially useful
iron-chelating agents and as strong anti-oxidative substances (Graziano et al., 1974; Maoka et al., 1996, 1997;
Rice-Evans and Packer, 1998). We have previously
reported the isolation and identification of the threo and
erythro isomers of guaiacylglycerol 8'-vanillic acid
ethers (1a and 1b) and of other compounds from the
methanol extract of the fruit of B. orientalis, and we have
shown that these compounds exhibit radical-scavenging
activities (Sakushima et al., 1994, 1995, 1997). As a
continuation of this investigation, we have succeeded in
isolating guaiacylglycerol-7'-O-methyl 8'-vanillic acid
ethers (2) and the related compound 4 from the same
source, and here we report the structural elucidation of
these isolates based on of UV, MS, 1H- and 13C-NMR
spectral data, including NOE, DEPT, two-dimensional
shift correlation, HMQC and HMBC analysis.
injected into a Shimadzu (Kyoto, Japan) model 6AD LC
system fitted with a Nucleosil 5 C18 (Nomura Chemicals,
Seto City, Japan) column (250 4 mm i.d.) and equipped
with a UV detector set at 280 nm. The column was eluted
with water:methanol (2:3) at a flow rate of 0.5 mL/min
with a pressure drop of 24 MPa/cm.
EXPERIMENTAL
HPLC analyses. Methanolic solutions of samples were
* Correspondence to: A. Sakushima, Faculty of Pharmaceutical Sciences,
Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 0610293, Japan.
Email: sakushi@post.hoku-iryo-u.ac.jp
Contract/grant sponsor: Ministry of Education, Science, Sports and Culture of
Japan.
Copyright # 2003 John Wiley & Sons, Ltd.
Spectral analyses. 1H- and 13C-NMR spectra were
recorded at 400 and 100 MHz, respectively, using a Jeol
(Tokyo, Japan) model EX 400 spectrometer. Samples
were dissolved in CD3OD. Chemical shifts are given
in ppm relative to TMS as internal standard. EI/MS were
measured by direct inlet using a Jeol model JMS
GCMATE mass spectrometer at an electron energy of
70 eV and an ion source temperature of 200°C.
Received 8 August 2001
Revised 30 January 2002
Accepted 5 February 2002
LIGNANS FROM BOREAVA ORIENTALIS
Plant material. Plants of Boreava orientalis were
collected near Ankara, Turkey, in 1990. A voucher
specimen is lodged in the Ankara Üniversitesi Eczacilik
Fakültesi herbaryumu (AEF).
Extraction and Isolation. Dried fruit (1 kg) was
extracted with petroleum ether (1 L 3), in order to
remove the oil, and then with methanol (1 L 3). The
concentrated methanolic extract was suspended in water
(1 L) and extracted successively with diethyl ether
(400 mL 4), chloroform (400 mL 4), ethyl acetate
(400 mL 4), and butanol (400 mL 4). The chloroform extract (3.7 g) was subjected to CC over silica gel
eluted with a gradient of chloroform:methanol; fractions
23 and 24 were purified by silica gel CC and preparative
HPLC as described previously (Sakushima et al., 1997)
to give 3a (2.2 mg) and 3b (1.9 mg), respectively. The
ethyl acetate extract (1.1 g) was subjected to CC using a
Sephadex LH-20 column eluted with water and methanol; fractions 15 and 16 were purified by LH-20 CC
eluted with a gradient of water:methanol to give 2a
(4.2 mg) and 2b (2.4 mg), respectively. The butanol
extract (3 g) was subjected to LH-20 CC eluted with
water and methanol; fraction 5, which eluted with 30%
aqueous methanol, was re-chromatographed on LH-20
eluted with a gradient of water:methanol. The fraction
which contained 4 was purified using Sephadex G-10 and
preparative HPLC as described previously (Sakushima et
al., 1997) to yield 2.5 mg of the compound.
Base hydrolysis of 2a and 2b. A sample of the
compound (0.5 mg of 2a or 0.6 mg of 2b) was stirred
with 0.5 M sodium hydroxide (1 mL) at room temperature
for 24 h. The reaction mixture was adjusted to pH 6.0
with dilute hydrochloric acid, extracted with ethyl acetate
(3 mL), the extract washed with water (1 mL 3) and
then evaporated to dryness in vacuo. The residue was
analysed by HPLC.
Acidic hydrolysis of 2a and 2b. A sample of the
compound (0.5 mg of 2a or 0.6 mg of 2b) was refluxed
with 3% hydrochloric acid (1 mL) for 2 h. The reaction
mixture was extracted with ethyl acetate (3 mL), the
extract washed with water (1 mL 3) and then evaporated to dryness in vacuo. The residue was analysed by
HPLC.
Determination of 2a and 2b. Dried fruit (100 g) was
extracted with petroleum ether, in order to remove the oil,
and then with ethanol. The concentrated ethanol extract
was suspended in water and extracted successively with
diethyl ether, chloroform, ethyl acetate, and butanol. The
concentrated chloroform and ethyl acetate extracts were
subjected to silica gel CC eluted with chloroform:ethanol. Fractions containing 2a and 2b were purified by
preparative HPLC as described previously (Sakushima et
al., 1997). The retention times (R t) and 1H-NMR spectral
data of the compounds thus purified agreed with those
reported previously for 2a and 2b.
Checking for artefact formation. A sample (0.5 mg) of
guaiacylglycerol 8'-vanillic acid ether was dissolved in
ethanol (3 mL), stored at room temperature for 1 week
and then heated in boiling water for 3 h. The absence of
guaiacylglycerol-7'-O-ethyl 8'-vanillic acid ether in the
Copyright # 2003 John Wiley & Sons, Ltd.
49
treated solution was confirmed by HPLC and from 1HNMR spectral data.
RESULTS AND DISCUSSION
Threo guaiacylglycerol-7'-O-methyl 8'-vanillic acid
ether (2a)
Colourless amorphous powder; melting point, 85–88°C;
HR-EI/MS m/z 378.13076 [M], corresponding to
C19H22O8 (calculated 378.13140); brown colour following FeCl3 reaction; TLC [silica gel, EtOAc:MeCOEt:
HCOOH:C6H6:H2O (4:3:1:1:2; upper layer); system A],
R f 0.90 (R f 0.80 for 1a); HPLC [H2O:MeOH (2:3);
solvent A], R t 15.7 min; UV lmax (nm) in MeOH (e), 257
(6699), 285.5 (4799); IR n (cm 1) film— 3100–3200
(OH), 1700 (—COO—), 1602 (C=C), 1558 (aromatic
C=C), 1508 (aromatic C=C), 1418 (aromatic C=C),
1269 (OMe), 1220 (C—O), 1222, 1032 (C—O); EI/MS
m/z (%)— 378 [M] (27.2), 316 [M–C2H6O2] (20.1),
211 [M–C9H11O3] (6.7), 180 [M–C10H14O4] (15.6),
168 [C9H11O3 H] (100.0), 167 [C9H11O3)] (66.0),
152 [C8H7O3 H] (34.6), 137 [C7H5O3] (34.4), 119
(7.7), 91 (5.4); 1H- and 13C-NMR spectra (Table 1).
Erythro guaiacylglycerol-7'-O-methyl 8'-vanillic acid
ether (2b)
Colourless amorphous powder; HR-EI/MS m/z
378.13397 [M], corresponding to C19H22O8 (calculated
378.13140); brown colour following FeCl3 reaction; TLC
[system A], R f 0.90; HPLC (solvent A), R t 15.8 min; UV,
MS and IR data as for 2a; 1H- and 13C-NMR spectra
(Table 1).
Threo guaiacylglycerol 8'-vanillin ether (3a)
Colourless amorphous powder; melting point, 67–71°C;
HR-EI/MS m/z 348.1211 [M], corresponding to
C18H20O7 (calculated 348.1209); brown colour following
FeCl3 reaction. TLC [system A], R f 0.82. HPLC (solvent
A), R t 16.1 min; UV lmax (nm) in MeOH (e)—226
(15376), 279 (8066), 304 (5100); IR n (cm 1) film—
3100–3200 (OH), 2963 (CH), 1734 (—COH—), 1559
(C=C), 1507 (aromatic C=C), 1457 (aromatic C=C),
1419 (aromatic C=C), 1270 (OMe), 1161 (C—O), 1032
(C—O); EI/MS m/z (%)—348 [M] (<5%), 300 [M–
(CH4O2)] (18.1), 211 (12.7), 178 [M–H2O–
(C8H9O3)] (77.7), 153 [C8H9O3] (37.7), 152
[C8H7O3 H] (66.9), 151 [C8H7O3] (100.0), 137
[C7H5O3] (34.2), 125 (13.4), 123 [C7H7O2] (26.0), 119
(13.3), 93 (21.6), 91 (14.8); 1H- and 13C-NMR spectra
(Table 2).
Erythro guaiacylglycerol 8'-vanillin ether (3b)
Colourless amorphous powder; slightly soluble in chloroform, brown colour following FeCl3 reaction; TLC
[system A], R f 0.82; HPLC (solvent A), R t 16.4 min;
UV, MS and IR data as for 3a; 1H- and 13C-NMR spectra
(acetone, d6) (Table 2); 1H-NMR (400 MHz, CDCl3) d
3.79–3.95 (2H, m, 9-CH2-), 3.86 (3H, s, -OMe), 3.91 (3H,
s, -OMe), 4.38 (1H, m, 8'-CH-), 4.97 (1H, d, J = 5.4, 7'CH-), 6.87–7.42 (6H, Ar H), 9.85 (1H, s, CHO); literature
Phytochem. Anal. 14: 48–53 (2003)
50
A. SAKUSHIMA ET AL.
Table 1. 1H- and 13C-NMR spectral dataa of the compounds 1, and 2a/2b
1ab
C
Benzoic acid moiety
1
124.7
2
114.2
3
148.1
4
154.0
5
117.0
6
124.3
7
167.3
56.3
3-OCH3
2ab
H
7.56(d, J = 2.0 Hz)
7.21(d, J = 8.3 Hz)
7.58(dd, J = 8.3, 2.0 Hz)
3.81(s)
Guaiacylglycerol moiety
1'
133.8
2'
111.6
7.10(d, J = 2.0 Hz)
3'
146.9
4'
151.0
5'
115.2
6.76(d, J = 8.0 Hz)
6'
120.5
6.90(dd, J = 8.0, 2.0 Hz)
7'
73.7
4.92(d, J = 5.4 Hz)
8'
86.9
4.47(m)
9'
62.0
a, 3.75(dd, J = 3.9,
12.2 Hz)
b, 3.57(dd, J = 5.9,
12.2 Hz)
56.5
3.90(s)
3'-OCH3
7'-OCH3
a
b
C
124.1
114.4
148.4
154.4
115.4
124.3
167.3
56.3
130.7
112.0
147.3
150.8
116.3
121.5
84.0
85.2
62.0
56.5
57.0
2bb
H
7.55(d, J = 2.0 Hz)
7.15(d, J = 8.3 Hz)
7.58(dd, J = 8.3, 2.0 Hz)
3.89(s)
7.06(d, J = 2.0 Hz)
6.80(d, J = 7.8 Hz)
6.87(dd, J = 7.8, 2.0 Hz)
4.44(d, J = 6.4 Hz)
4.55(m)
a, 3.65(dd, J = 3.9,
11.7 Hz)
b, 3.53(dd, J = 6.4,
11.7 Hz)
3.83(s)
3.20(s)
C
124.3
114.3
148.2
153.6
115.1
124.2
167.3
56.3
H
7.49(d, J = 2.0 Hz)
7.04(d, J = 8.3 Hz)
7.54(dd, J = 8.3, 2.0 Hz)
3.82(s)
130.6
112.4
147.3
150.8
116.2
122.0
84.3
83.5
61.9
6.77(d, J = 8.3 Hz)
6.87(dd, J = 8.3, 2.0 Hz)
4.43(d, J = 5.9 Hz)
4.59(m)
3.78(dd, J = 4.9 Hz, 2H)
56.4
58.0
3.83(s)
3.20(s)
7.06(d, J = 2.0 Hz)
Chemical shifts in ppm (J values in Hz).
Spectra measured in acetone-d6 (35°C).
1
H-NMR (400 MHz, CDCl3–D2O; Katayama et al.,
1981): d 3.80–3.95 (2H, m, 9-CH2-), 3.84 (3H, s,
-OMe), 3.89 (3H, s, -OMe), 4.41 (1H, m, 8-CH-), 4.95
(1H, d, J = 5.5, 7-CH-), 6.80–7.38 (6H, Ar H), 9.85 (1H,
s, CHO).
Threo guaiacylglycerol 8'-(4-hydroxymethyl-2methoxyphenyl) ether (4)
Colourless amorphous powder; melting point, 67–71°C;
HR-EI/MS m/z 387.1058 [M Na], corresponding to
C18H20O8Na (calculated 387.10582); brown colour
following FeCl3 reaction; TLC [system A], R f 0.83;
HPLC (solvent A), R t 8.7 min; UV lmax (nm) in MeOH
(e)— 250 (sh), 282 (2655), 328.5 (sh); IR n (cm 1) film—
3100–3300 (OH), 2956 (CH), 1602 (C=C), 1507
(aromatic C=C), 1471 (aromatic C=C), 1456 (aromatic
C=C), 1300 (OMe), 1150 (C—O); EI/MS m/z (%)— 350
[M], 332 [M–H2O], 211, 180, 168 (100), 166, 154,
153 (80.8), 151 (62.1), 137 (38.3), 124 (35.2), 109 (4.0),
107 (24.4), 93 (17.5); 1H- and 13C-NMR spectra (Table
2).
Compounds 2a and 2b were obtained as pale yellow
powders by preparative HPLC, and both exhibited a
positive ferric chloride reaction. IR spectra suggested the
presence of hydroxyl, carbonyl and aromatic rings. UV
spectra showed absorption maxima at 257 and 286 nm,
and shifts of the maxima upon addition of sodium
ethoxide were similar to those observed for isomers of
guaiacylglycerol 8'-vanillic acid ether (Sakushima et al.,
1997). Neither compound could be hydrolysed with 3%
hydrochloric acid or 0.5 M sodium hydroxide as has been
previously noted for isomers 1a and 1b. The compounds
showed molecular weights of 378 amu whilst their
Copyright # 2003 John Wiley & Sons, Ltd.
molecular formulae were determined to be C19H22O8
by HR-EI/MS. The EI/MS fragment ions at m/z 123, 137,
151 [M-227], 167 [M-211], 180, 211 and 278 [M100] were due to the loss of vanillic acid, guaiacyl and
guaiacylglycerol residues. The fragment ion at m/z 211
[M-167] was due to the elimination of a deprotonated
vanillic acid moiety (167 amu), suggesting the presence
either of a vanillic acid residue on the guaiacylglycerol
moiety (Houghton, 1985), or of guaiacyl methanol
methyl ether moieties (167 amu).
Both the ether location in guaiacylglycerol and the
relative stereochemistry were determined by detailed
analysis of the 1H- and 13C-NMR spectra, and from
results of two-dimensional shift correlation, DEPT,
HMQC, HMBC and NOE experiments. The 1H-NMR
spectra of both 2a and 2b showed the presence of two sets
of ABX-type signals in the aromatic region, two signals
from methine protons, and two aryl methoxy signals and
one alcoholic methyl ether signal in the aliphatic region
(Table 1). Coupling constants and chemical shifts of the
8'-H methine proton in 2a and 2b were similar to those of
1a (Table 1). However, the signals attributed to the
proton of C-7' of the glycerol core were shifted upfield by
ca. 0.4 ppm when compared with 1a. The methyl group
was thus determined to be at the C-7' position in the
guaiacylglycerol unit. Chemical shifts for 2a and 2b in
the 13C-NMR spectrum agreed with values estimated for
1a, except for a downfield shift of ca. 10 ppm of the C-7'
signals of both 2a and 2b, compared with 1a, indicating
etherification of the hydroxyl group at C-7 in the
guaiacylglycerol moiety. Therefore, the alcoholic methyl
ether was identified to be at the C-7' position of the
glycerol core, and this was supported by the fragment ion
of m/z 167 in the EI/MS of 2a and 2b.
Phytochem. Anal. 14: 48–53 (2003)
Copyright # 2003 John Wiley & Sons, Ltd.
Table 2. 1H- and 13C-NMR spectral dataa of the compounds 3a/3b and 4
3ab
C
Guaiacylglycerol moiety
1'
133.7
2'
111.4
3'
147.1
4'
151.5
5'
115.2
6'
120.4
7'
73.7
8'
85.1
9'
61.0
3'-OCH3
b
c
7.43(d, J = 2.0 Hz)
7.31(d, J = 8.3 Hz)
7.46(dd, J = 8.3, 2.0 Hz)
9.84(s)
3.93(s)
7.11(d, J = 2.0 Hz)
6.76(d, J = 8.3 Hz)
6.90(dd, J = 8.0, 2.0 Hz)
4.92(d, J = 5.9 Hz)
4.56(m)
a, 3.62(dd, J = 5.9, 11.8 Hz)
b, 3.52(dd, J = 3.4, 11.8 Hz)
3.81(s)
C
131.6
111.3
148.0
154.9
116.1
126.2
191.2
56.2
H
7.38(d, J = 2.0 Hz)
7.20(d, J = 8.3 Hz)
7.42(dd, J = 8.3, 2.0 Hz)
9.82(s)
3.87(s)
C
130.6
110.9
148.9
153.5
115.9
127.0
191.2
56.3
133.2
111.8
150.9
148.9
115.4
123.7
63.2
56.1
4c
134.0
111.7
146.8
151.6
116.1
120.7
73.9
85.2
62.2
6.73(d, J = 8.3 Hz)
6.91(dd, J = 8.3, 2.0 Hz)
4.91(d, J = 5.3 Hz)
4.62(m)
a, 3.80(overlapping)
133.2
111.4
147.8
145.6
114.5
119.9
72.5
83.8
60.8
56.3
3.81(s)
56.1
7.13(d, J = 2.0 Hz)
H
7.46(br-s)
6.91(d, J = 8.3 Hz)
7.40(d, J = 8.3 Hz, br-s)
4.26(overlapping)
3.68(s)
6.96(d, J = 2.0 Hz)
6.67(d, J = 8.3 Hz)
6.79(dd, J = 8.3, 2.0 Hz)
4.87(d, J = 5.3 Hz)
4.49(m)
a, 3.73(dd, J = 5.9, 11.7 Hz)
b, 3.51(dd, J = 5.9, 11.7 Hz)
3.79(s)
Vanillyl
alcohol
C
133.5
111.9
147.8
145.3
115.3
120.5
64.1
56.1
Chemical shifts in ppm (J values in Hz).
Spectra measured in acetone-d6 (35°C).
Spectra measured in acetone-d6:D2O (1:1) (45°C).
51
Phytochem. Anal. 14: 48–53 (2003)
a
56.3
H
Vanillic
acid
C
LIGNANS FROM BOREAVA ORIENTALIS
Benzoic acid moiety
1
131.0
2
111.2
3
148.0
4
155.3
5
116.3
6
126.3
7
191.2
56.1
3-OCH3
3bb
52
A. SAKUSHIMA ET AL.
Table 3. Comparison of the 1H-NMR spectral dataa of the Isomers of compounds 1, 2, 3 and 4
threo isomer (compound suf®x a)
Compounds
1a and 1bb
2a and 2bb
3a and 3bb
4c
a
b
c
erythro isomer (compound suf®x b)
7'
8'
9'
7'
8'
9'
4.92
(5.4)
4.44
(6.4)
4.92
(5.9)
4.87
(5.3)
4.47
(m)
4.55
(m)
4.56
(m)
4.49
(m)
3.75, 3.57
(3.9, 5.9, 12.2)
3.65, 3.53
(3.9, 6.4, 11.7)
3.62, 3.52
(3.4, 5.9, 11.8)
3.73, 3.51
(5.9, 11.7)
4.90
(5.4)
4.43
(5.9)
4.90
(5.3)
4.54
(m)
4.59
(m)
4.62
(m)
3.82
(overlapping)
3.78
(4.9)
3.8
(overlapping)
Chemical shifts in ppm (J values in Hz).
Spectra measured in acetone-d6 (35°C).
Spectra measured in acetone-d6:D2O (1:1) (45°C).
Assignment of the relative configuration was based on
H-NMR chemical shifts for protons of the glycerol core
in guaiacylglycerol (Table 3). 1H-NMR spectral data of
the glycerol cores of both 2a and 2b were similar to those
of the threo and erythro isomers of guaiacylglycerol 8'vanillic acid ether reported previously (Sakushima et al.,
1997). Downfield shifts of 8'- and 9'-H were attributed to
the erythro isomer, and upfield shifts were attributed to
the threo isomer. Therefore, 2a and 2b were determined
to be threo and erythro guaiacylglycerol-7'-O-methyl 8'vanillic acid ethers, respectively. Both compounds are
presumed to be naturally-occurring and not artefacts,
since they were isolated from neutral solution (Brunow
and Lundguist, 1991), and a compound related to 2 has
been isolated from Myristica fragrans (Hattori et al.,
1986). Furthermore, 2 could be identified by HPLC and
1
H-NMR in fruit extracts prepared with ethanol instead of
methanol.
Compounds 3a and 3b were obtained as pale yellow
powders, and both exhibited a positive ferric chloride
reaction. IR spectra showed the presence of hydroxyl,
carbonyl and aromatic rings, as for 2a and 2b, whilst the
UV spectra showed absorption maxima at 227, 279 and
304 nm. The 1H-NMR spectra of 3a and 3b were
characterised by the presence of aldehyde protons at
9.82 and 9.83 ppm and signals of six aromatic protons
and four aliphatic protons due to guaiacylglycerol and
vanillin. The chemical shifts for the guaiacylglycerol
moieties in the 13C-NMR spectra of both 3a and 3b
agreed with those of isomers of guaiacylglycerol 8'vanillic acid ether, and the chemical shifts for the other
moiety agreed with those of vanillin (Table 2). The
compounds showed molecular weights of 348 amu whilst
their molecular formulae were determined to be
C18H20O7 by HR-EI/MS. The EI/MS fragment ions at
m/z 123, 137, 151 [M-227], 167 [M-211], 180, 211 and
278 [M-100] were due to the loss of vanillin, guaiacyl
and guaiacylglycerol residues. Compounds 3a and 3b
1
were, therefore, identified as threo and erythro guaiacylglycerol 8'-vanillin ethers. These compounds have
also been identified as products of the biodegradation of
lignin (Katayama et al., 1980, 1981), and the diastereomeric compounds have been isolated from Larix
leptolepis (Miki et al., 1980).
Compound 4 was obtained as a pale yellow powder,
and exhibited a positive ferric chloride reaction. The
molecular formula was determined to be C18H22O7 by
HR-EI/MS. The IR, UV, 1H- and 13C-NMR spectra were
similar to those of 3a; the 1H-NMR spectrum of 4
exhibited a resonance of a hydroxymethyl group at
4.26 ppm, which was identified by a C-H COSY shift
correlation. The 1H-NMR spectral data of the glycerol
core in the guaiacylglycerol moiety of 4 resembled that of
3a rather than 3b (Table 3). In the 13C-NMR spectrum,
chemical shifts of the guaiacylglycerol moiety of 4
agreed with those of guaiacylglycerol 8'-vanillic acid
ether, and chemical shifts for the other moiety matched
those of vanillyl alcohol (Table 2). Since the EI/MS
fragmentation pattern was similar to that of 3a,
compound 4 was finally identified as threo guaiacylglycerol 8'-(4-hydroxymethyl-2-methoxyphenyl) ether, a
new natural product. However, similar to the case for
3a and 3b, compound 4 has been previously identified as
a breakdown product of lignin (Katayama et al., 1981;
Shen and Heiningen, 1992).
Acknowledgements
The authors wish to thank Dr Kazuyuki Kamata (Faculty of
Pharmaceutical Sciences, Health Sciences University of Hokkaido,
Japan) for support and encouragement in preparing this manuscript,
and Miss Yoko Akashima (Central Analytical Laboratory, Health
Sciences University of Hokkaido, Japan) for recording MS and NMR
spectra. This work was supported in part by a grant-in-aid for High
Technology Research from the Ministry of Education, Science, Sports
and Culture of Japan.
REFERENCES
Brunow G and Lundguist K. 1991. On the acid-catalysed
alkylation of lignins. Holzforsch 45: 37±40.
Graziano J, Grady RW and Cerami A. 1974. The identi®cation
of 2,3-dihydroxybenzoic acid as a potentially useful ironchelating drug. J Pharm Exp Therapeut 190: 570±575.
Copyright # 2003 John Wiley & Sons, Ltd.
Hattori M, Hada S, Watahiki A, Ihara H, Shu Y-Z, Kakiuchi N,
Mizuno T and Namba T. 1986. Studies on dental caries
prevention by traditional medicines. X. Antibacterial
action of phenolic compounds from mace against
Streptcoccus mutans. Chem Pharm Bull 34: 3885±3893.
Phytochem. Anal. 14: 48–53 (2003)
LIGNANS FROM BOREAVA ORIENTALIS
Houghton PJ. 1985. Lignans and neolignans from Buddleja
davidii. Phytochemistry 24: 819±826.
Katayama T, Nakatsubo F and Higuchi T. 1980. Initial
reactions in the fungal degradation of guaiacylglycerolb-coniferyl ether, a lignan substructure model. Arch
Microbiol 126: 127±132.
Katayama T, Nakatsubo F and Higuchi T. 1981. Syntheses of
arylglycerol-b-aryl ethers. Mokuzai Gakkaishi 27: 223±
230.
Maoka T, Sakushima A, Coskun M and Ito H. 1996. Antioxidative activity of phenolic compounds of Boreava
orientalis. J Jap Oil Chem Soc 45: 671±673.
Maoka T, Ito H, Sakushima A, Ohno K, Coskun M and Nishibe
S. 1997. Comparison of anti-oxidative activity of phenolic
compounds in Boreava orientalis and their relative
compounds. J Jap Oil Chem Soc 46: 1399±1402.
Miki K, Takehara T, Sasaya T and Sakakibara A. 1980. Lignans
of Larix leptolepis. Phytochemistry 19: 449±453.
Rice-Evans CA and Packer L. 1998. The Flavonoids in Health
and Disease. Marcel Dekker: New York; 35±59.
Copyright # 2003 John Wiley & Sons, Ltd.
53
Sakushima A, Coskun M, Tanker M and Tanker N. 1994. A
sinapic acid ester from Boreava oreientalis. Phytochemistry 35: 1481±1484.
Sakushima A, Coskun M and Maoka T. 1995. Hydroxybenzoic
acids from Boreava orientalis. Phytochemistry 40: 257±
261.
Sakushima A, Coskun M, Maoka T and Nishibe S. 1997.
Separation of guaiacylglycerol-8'-vanillic acid ether isomers from Boreava orientalis. Nat Prod Lett 11: 31±36.
Shen X and Heiningen AV. 1992. Synthesis of b-O-4 lignin
model dimmers and their chlorinated derivatives. Can J
Chem 70: 1754±1761.
Tanker M and Yenen M. 1978. Boreava orientalis. J Fac
Pharm Ankara Univ 8: 1.
Tanker M, Ertan M, Coskun M, Sariseker N and Yurdesin T.
1983. The investigation of possibilities in Turkey with
regards to the antibiotic industry. Turkish J Med Sci 7: 99±
108.
Phytochem. Anal. 14: 48–53 (2003)