A flavonol glycoside-lignan ester and accompanying acylated glucosides from Monochaetum multiflorum

Article abstract of DOI:10.1016/S0031-9422(01)00247-3

Four acylated glycosides along with six known glycosides were isolated from the leaves of Monochaetum multiflorum. The new compounds were characterized as 4.0-(6′-O-galloyl- β- glucopyranosyl)-cis-p-coumaric acid, 6′-O- galloylprunasin, benzyl 6′-O-galloyl-β-glucopyranoside, and a novel diester of tetrahydroxy-μ-truxinic acid with 2 mol of hyperin (monochaetin), based on NMR and MS spectral data and chemical evidence.

Full text of DOI:10.1016/S0031-9422(01)00247-3

Phytochemistry 58 (2001) 321–327
www.elsevier.com/locate/phytochem
A flavonol glycoside-lignan ester and accompanying acylated
glucosides from Monochaetum multiflorum
Jose H. Isaza, Hideyuki Ito, Takashi Yoshida*
Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan
Received 23 January 2001; received in revised form 12 April 2001
Abstract
Four acylated glycosides along with six known glycosides were isolated from the leaves of Monochaetum multiflorum. The new
compounds were characterized as 4-O-(60-O-galloyl-b-glucopyranosyl)-cis-p-coumaric acid, 60-O-galloylprunasin, benzyl 60-O-gal-
loyl-b-glucopyranoside, and a novel diester of tetrahydroxy-m-truxinic acid with 2 mol of hyperin (monochaetin), based on NMR
and MS spectral data and chemical evidence. # 2001 Elsevier Science Ltd. All rights reserved.
Keywords: Monochaetum multiflorum; Melastomataceae; Galloylglucoside; Galloylprunasin; Di-hyperin ester of tetrahydroxy-m-truxinic acid
1. Introduction
to extraction successively with Et2O, EtOAc and n-
BuOH. The EtOAc extract was submitted to column
chromatography over Toyopearl HW-40, followed by
gel chromatography on MCI gel CHP-20P and pre-
parative HPLC to yield 10 glycosidic compounds (1–
10). Six among them were identified as trifolin (1) (Bar-
bera et al., 1986), hyperin (2) (Bennini et al., 1992),
quercetin 3-(60-O-caffeoyl)-b-d-galactoside (3) (Shige-
matsu et al., 1982), isoquercitrin (4), quercetin 3-(60-O-
caffeoyl)-b-d-glucopyranoside (5) (Lin and Wang, 1987)
As part of a phytochemical study on Colombian mel-
astomataceous plants, we previously reported the isola-
tion and structural elucidation of new oligomeric
hydrolyzable tannins, nobotanins O and P, along with
known ellagitannins characteristic of this family, from
Tibouchina multiflorum (Yoshida et al., 1999). Chroma-
tographic analysis by HPLC suggested that Mono-
chaetum multiflorum (Bompl.) Naudin, a shrub endemic
to Colombia, is also rich in polyphenols. The aerial part
of the plant has been traditionally used as a topical
treatment for infections and skin injuries in parts of
Colombia. However, its chemical constituents have been
little investigated. Here, we report the isolation and
characterization of ten compounds (1–10), including
four new acylated glycosides (7–10) from the leaves of
M. multiflorum; one of these is a novel flavonol glyco-
side diester of a lignan possessing a cyclobutane ring.
and
4-O-b-d-glucopyranosyl-2-O-methylphloroaceto
phenone (6) (Konda et al., 1991) by spectroscopic
means and comparison with reference samples or
reported data.
Compound 7, [a]D À14.3ꢀ, was obtained as an amor-
phous powder. The molecular formula, C22H22O12, was
established by HRESIMS. The 1H NMR spectrum
indicated the presence of a galloyl group (ꢀ 7.13, 2H, s),
a 1,4-disubstituted benzene ring (ꢀ 7.04, 7.71, each 2H,
d, J=8.5 Hz), vinyl protons (ꢀ 5.83, 6.84, each 1H, d,
4
J=12.5 Hz), and signals characteristic of a C1-gluco-
2. Results and discussion
pyranosyl residue. The coupling constant of the signal
at ꢀ 5.03 (d, J=7.5 Hz) assignable to an anomeric pro-
ton of the glucose indicated a b-configuration for the
glucosidic linkage. These spectral features as well as two
carboxyl carbon signals at ꢀ 166.9 and 167.9 in the 13C
NMR spectrum indicated that 7 is a galloyl ester of 4-O-
b-glucopyranosyl-cis-p-coumaric acid. The NOESY
spectrum of 7 verified this structure, with NOE correla-
tions in a sequence of the signals of ꢀ 5.83$ꢀ 6.84$ꢀ
Dried leaves of M. multiflorum were extracted with
aqueous acetone. The concentrated solution was subjected
*Corresponding author. Tel.: +81-86-251-7936; fax: +81-86-251-
7936.
E-mail
(T. Yoshida).
address:
yoshida@pheasant.pharm.okayama-u.ac.jp
0031-9422/01/$ - see front matter # 2001 Elsevier Science Ltd. All rights reserved.
PII: S0031-9422(01)00247-3

322
J.H. Isaza et al. / Phytochemistry 58 (2001) 321–327
a new compound though 4-O-b-glucopyranosyl-cis-p-
coumaric acid has been described in the literature
(Lemmich, 1995).
Compound 8, [a]D À17.0ꢀ, was obtained as an amor-
phous powder. Its ESIMS showed an [M+NH4]+ peak
at m/z 465 and the molecular formula was determined
1
as C21H21NO10 by HRESIMS. The H NMR spectrum
of 8 showed signals ascribable to a galloyl (ꢀ 7.17, 2H,
s), a monosubstituted benzene ring (ꢀ 7.53, 2H, dd,
J=2, 7.5 Hz; 7.41–7.44, 3H, m) and a sugar residue. A
methine proton was also observed as a singlet at ꢀ 5.82.
The presence of a 6-O-galloylated 4C1-glucopyranose
residue was suggested by the 13C NMR spectrum which
showed sugar signals similar to those of 7, although the
chemical shift of an anomeric proton signal (ꢀ 4.40) in 8
markedly differed from that in 7 (ꢀ 5.03). Based on these
spectral characteristics along with the signal at ꢀ 118.8
assignable to a nitrile carbon, compound 8 was assumed
to be 60-O-gallate of prunasin (Seigler, 1975) or its (2S)
isomer, sambunigrin (Jensen and Nielsen, 1973), which
was substantiated by correlations in HMBC and
NOESY as shown in the formula. The configuration at
C-2 was confirmed to be R by production of prunasin,
[ꢁ]D À26.0ꢀ, along with gallic acid upon enzymatic
hydrolysis of 8 with tannase. The difference in the che-
mical shifts of the anomeric protons in 7 and 8 can be
explained by an anisotropic effect of the benzene ring
directly attached to the glucose in 7.
7.71$ꢀ 7.04$ꢀ 5.03 as shown in formula (7). The
location of the galloyl unit at O-6 of the glucopyranose
core was evident from low-field shifts of the H-60 signals
(ꢀ 4.63, 4.28). Furthermore, the galloylglucose carbon
signals observed in the 13C NMR spectrum of 7 were
almost superimposable on those reported for 6-O-gal-
loylglucose (Nonaka and Nishioka, 1983) except for a
large downfield shift for the anomeric carbon. Based on
these data, compound 7 was identified as 4-O-(60-O-
galloyl-b-glucopyranosyl)-cis-p-coumaric acid, which is
Compound 9, [a]D À29.4ꢀ, had the molecular formula
1
C20H22O10 as revealed by HRESIMS. The H and 13C
NMR spectra of 9 closely resembled those of 8 except
for the presence of a methylene group [ꢀH 4.61, 4.82
(each d, J=12 Hz); ꢀC 70.9] instead of the cyano group
at the benzyl position in 8. Both methylene protons
disclosed clear NOEs with an anomeric proton. There-

J.H. Isaza et al. / Phytochemistry 58 (2001) 321–327
323
fore, compound 9 was characterized as benzyl 60-O-gal-
loyl-b-glucopyranoside.
Table 1
13C NMR spectral dataa for the flavonol glycoside moiety of 10 and 3
Compound 10, [a]D À25.0ꢀ, obtained as a yellow
amorphous powder, had the UV absorption character-
istic of a flavonol skeleton (lmax 358, 286 sh, 267 sh, 258
nm). A characteristic feature on normal phase HPLC
was the longer retention time than for the flavonoid
glycosides 1–5, suggesting a larger molecular size than
the ordinary flavonoid. Its ESIMS exhibited an [M+
H]+ peak at m/z 1253 and the molecular formula was
established as C60H52O30 by HRESIMS. Although the
1H and 13C NMR spectra of 10 were complicated
because most signals appeared in pairs having close
chemical shifts and some were overlapped, full assign-
10
3
Quercetin moiety
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-10
C-20
C-30
C-40
C-50
C-60
156.34b, 156.25b
133.7, 133.6
177.4, 177.4
161.26, 161.25
98.8, 98.8
156.2
133.4
177.4
161.1
98.6
164.2, 164.1
93.57, 93.55
156.34b, 156.34b
104.0, 104.0
121.20, 121.18
116.14, 116.13
144.82, 144.81
148.5, 148.5
115.3, 115.3
121.86, 121.84
164.2
93.4
156.2
103.8
121.0
115.1
144.7
148.4
115.9
121.9
1
ment of the signals was achieved by means of H-1H
COSY, TOCSY, 1H J-resolved and ꢀHMQC spectro-
scopy at an elevated temperature (50 C) in DMSO-d6.
These 1H and 13C NMR (Table 1) spectra included pairs
of signals similar to those of quercetin 3-O-galactoside
(hyperin 2), suggesting that 10 contains two hyperin
moieties. This was also substantiated by MS fragmen-
tation showing a successive loss of quercetin (Q) (m/z
951 [M+H–Q]+, 645 [M+H–2Q]+) as well as a base
peak at m/z 303 [Q+H]+. Large downfield shifts of the
galactose C-6 methylene protons relative to the corre-
sponding signals of 2 (ꢀ 3.28 for 2!ꢀ 3.52, 3.62 for 10; ꢀ
3.45 for 2!ꢀ 3.71, 3.84 for 10) indicated that both
galactose cores are acylated at O-6. The presence of a
di-(3,4-dihydroxyphenyl)cyclobutane dicarboxyl moiety
(lignan) as an acyl unit in the molecule was indicated by
Galactose moiety
C-100
C-200
C-300
C-400
C-500
C-600
102.0, 101.9
71.0, 71.0
72.9, 72.8
68.4, 67.7
73.0, 72.5
62.0, 63.3
101.8
71.2
73.2
67.9
75.7
60.1
126 MHz, DMSO-d6, 50 ꢀC.
Interchangeable.
a
b
ton [H-7 (H-70)] on the phenyl bearing-carbon and the
carboxyl-bearing carbons [C-80 (8)] (Table 2). The
HMBC spectrum also showed correlations of the car-
boxyl carbons with the C-6 methylene protons of both
galactoses. The configuration of the substituents on the
cyclobutane ring was established by the NOESY spec-
trum which showed clear NOE correlations among H-
2(6)/H-60 (20) and H-2 (20)/H-70 (H-7), which are only
possible in a m-truxinate arrangement. These correla-
tions revealed the preferred eclipsed conformation
between H-7 and H-6, and between H-70 and H-60,
which was consistent with the minimal steric energy
model calculated by MM2. A similar feature was
reported for the m-truxinic acid moiety of sargerinic acid
(Lu and Foo, 1999).
1
the following observations. (1) The H NMR spectrum
showed two ABX-type aromatic proton signals and an
AA0BB0 system of methine proton signals [each ddd,
J=10.5 Hz (cis), J=7.0 Hz (trans), J=2.0 Hz (long
range)], which is characteristic of tetrasubstituted cyclo
butane protons (Montaudo and Caccamese, 1973). (2)
In the 13C NMR spectrum, signals due to an acyl moi-
ety, C18H14O6, were observed as nine paired-varieties
with close proximity, among which seven partly over-
lapping pairs are of sp2 carbons including ester carbonyl
carbons (ꢀ 171.0, 171.2) and two pairs are of sp3 carbons
(ꢀ 40.1, 40.4; 46.1, 46.3). These carbon signals were
assignable to those of a cyclobutane ring possessing two
3,4-dihydroxyphenyl and two ester substituents by
HMQC and DEPT. Based on these data, the acyl unit in
10 was deduced to be either m-truxinyl-type ([7.70, 8.80]-
lignan) or a-truxillyl-type ([7.80, 8.70]-lignan) (Ben-
Efraim and Green, 1974), the former being preferred
because of the close similarity of chemical shifts and
coupling patterns of the cyclobutyl protons to those
reported for m-truxinic acid (12) (or its enantiomer)
rather than a-truxillic acid (13) (Ben-Efraim and Green,
1974). The proposed lignan structure in 10 was sub-
stantiated by the HMBC spectrum (Table 2), which
revealed three-bond correlations among most of the
protons and carbons including those between the pro-
Acid hydrolysis of a methylated derivative of 10 fol-
lowed by remethylation yielded an optically inactive
methyl ester (11) and penta-O-methylquercetin. The H
1
NMR spectral data for 11 were as expected for a sym-
metrical structure, and included a single carbomethoxyl
signal at d 3.37, shifted upfield by the shielding effect of
the cis-b-phenyl group (Ben-Efraim and Green, 1974).
Based on these data, the structure (10) for monochaetin
was established as shown in the formula.
Monochaetin is most plausibly formed from 3 via a
[2+2] photochemical addition process. Dimeric pro-
ducts having a cyclobutane ring produced from various
phenylpropanoid acids have been reported (Atta-ur-
Rahman et al., 1998; Lu and Foo, 1999; Seidel et al.,

324
J.H. Isaza et al. / Phytochemistry 58 (2001) 321–327
Table 2
1H and 13C NMR data and HMBC correlations for the m-truxinyl moiety of 10
Position
ꢀH
ꢀC
Observed three-bond correlation
1 (10)
2 (20)
129.6 (129.5)
H-5 (H-50), H-8 (H-80)
C-7 (C-70)
6.52 (6.54)
114.8 (114.9)
144.8
144.1 (144.0)
H-7 (H-70)
3 (30)
4 (40)
5 (50)
H-5, H-50
H-2 (H-20), H-6 (H-60)
C-1 (C-10, C-30)
6.59 (6.56)
6.30 (6.25)
3.89 (3.87)
115.2
6 (60)
7 (70)
C-4, C-20
H-7 (H-70)
C-2 (C-20), C-6 (C-60)
C-80 (C-8), C-9 (C-90)
H-2 (H-20), H-6(H-60), H-80 (H-8)
C-1 (C-10), C-70 (C-7), C-90 (C-9)
H-70 (H-7)
118.3 (118.1)
40.3 (40.1)
8 (80)
9 (90)
3.54 (3.46)
46.2 (46.3)
171.0 (171.2)
H-7 (H-70)
Galactose H-600 3.52, 3.84 (3.62, 3.71)
2000; Sudo et al., 2000; Wang et al., 2000). However,
only a few diflavonoid esters of dicarboxylic acid are
known (Itokawa et al., 1981; Horie et al., 1986). More
notably, only stachysetin isolated from Stachys aegyp-
tiaca (Labiatae) was reported as a flavone glycoside
truxinate ester (El-Ansari et al., 1995). Monochaetin is
thus the second analogue of such a flavonoid cyclodimer
in the m-truxinate form.
3.2. Plant material
The leaves of Monochaetum multiflorum were col-
lected near Manizales City, Caldas, Colombia and
identified by Dr. Gustavo Lozano C. A voucher speci-
men was deposited at Herbario Nacional de Colombia
(COL) (voucher No. 361696).
3.3. Extraction and isolation
3. Experimental
Dried leaves (400 g) of M. multiflorum were homo-
genized in 70% aqueous acetone, filtered and con-
centrated in vacuo. The concentrated solution was
subjected to liquid-liquid partition to give Et2O (4.6 g),
EtOAc (13.4 g), n-BuOH (33.8 g) extracts and aqueous
residue (54.3 g). The EtOAc extract (10.2 g) was frac-
tionated on a Toyopearl HW-40 (coarse grade) column
(2.2 cm i.d. ꢁ 45 cm) with aq. MeOH and a mixture of
acetone–MeOH–H2O in a step-wise gradient mode to
produce four fractions, (A) 40% MeOH (3.9 g), (B)
70% MeOH (2.2 g), (C) acetone–MeOH–H2O (2:5:3)
(3.4 g) and (D) acetone–H2O (7:3) (0.7 g).
Fraction A (3.5 g) was applied to a Toyopearl HW-40
(coarse grade) column (2.2 cm i.d. ꢁ 45 cm), this being
eluted with a step-wise water–MeOH gradient from 20
to 70% MeOH (CC-1-1). Fractions showing similar
HPLC patterns were pooled and further purified on a
YMC ODS AQ120 S-50 column (1.1 cm i.d. ꢁ 45 cm),
eluting with a binary step-wise gradient from water to
MeOH. In this way, fractions (281 mg) eluted with 20%
MeOH yielded 6 (36 mg) and the 25% MeOH eluate
(105 mg) gave 7 (9.0 mg), 8 (21 mg), and 9 (10 mg). The
30% eluate afforded 1 g of a mixture of 1, 2 and 4, from
which 50 mg was subjected to preparative HPLC (RP-2)
to give 1 (2.5 mg), 2 (23 mg) and 4 (15 mg). The 40–50%
MeOH eluate yielded 428 mg of a mixture, which after
purification with a combination of MCI gel CHP-20P,
3.1. General
1H (500 MHz) and 13C (126 MHz) NMR spectra were
recorded on a Varian VXR-500 spectrometer. ESI–MS
was performed with a Micromass Auto Spec OA–Tof
mass spectrometer using 0.1% NH4OAc in 50% MeOH
as solvent, at a flow rate of 0.02 ml minÀ1. Optical rota-
tions were conducted on a JASCO DIP-1000 polarimeter.
Normal phase (NP) HPLC was performed on a YMC
Pack Sil A-003 column (5 mm, 4.6 mm i.d.ꢁ250 mm), flow
rate 1.5 ml minÀ1, detected with UV 280 nm. Mobile
phases: (NP-1) n-hexane–MeOH–THF–HCOOH (55:33:
11:1) containing oxalic acid (450 mg lÀ1), (NP-2) n-hex-
ane–MeOH–THF–HCOOH (60:45:15:1) containing oxa-
lic acid (500 mg 1.2 lÀ1) and (NP-3) n-hexane–MeOH–
THF–HCOOH (47:39:13:1) containing oxalic acid (450
mg lÀ1). Analytical reversed-phase HPLC was performed
on a J’sphere ODS M-80 column (4.6 mm i.d. ꢁ 250 mm),
flow rate 1.0 ml minÀ1, 40 ꢀC, detector UV 280 nm; Mobile
phases: (RP-1) 0.01 M H3PO4–0.01 M KH2PO4–EtOH–
EtOAc (42.5:42.5:10:5) and (RP-2) 0.01 M H3PO4–0.01 M
KH2PO4–MeCN (42.5:42.5:15). Preparative HPLC was
carried out on a J’sphere ODS M-80 column (10 mm i.d.
ꢁ250 mm, 4 mm, 80 A,), detector MCPD 240–400 nm,
ꢀ
flow rate 3.0 ml minÀ1, 40 C, mobile phase RP-2.

J.H. Isaza et al. / Phytochemistry 58 (2001) 321–327
325
YMC ODS and preparative HPLC (RP-2) gave 1 (0.5
mg), 2 (7 mg), 4 (5.0 mg) and 10 (9.0 mg).
3.6. 60-O-Galloylprunasin (8)
Fraction B (2.0 g) from CC-1, (70% MeOH fraction)
was separated on a Toyopearl HW-40C (CC-1-2) eluted
with a binary step-wise gradient of MeOH (20–70%)
collecting each 5 ml fraction. Fractions 351–460 (380
mg) (Fr. B-1) and 501–530 (91.6 mg) (Fr. B-2) eluted
with 40% MeOH were further independently purified
on an MCI-gel CHP-20P (1.1 cm i.d. ꢁ 45 cm) chro-
matographic column eluted with a step-wise gradient of
EtOH (5 ! 60%). Fraction B-1 yielded 1 (0.2 mg), 2 (14
mg), 5 (12 mg) and 10 (59 mg) when eluted with 30%
EtOH. Fraction B-2 afforded a mixture (29 mg) of 3 and
5, when eluted with 30% EtOH. Final purification was
performed by preparative RP-HPLC as described above
to obtain 3 (7 mg) and 5 (10 mg).
A white amorphous powder, [a]D À17.0ꢀ (c 1.9,
MeOH). UV lmax MeOH nm (log "): 269 (2.8), 351
(2.4). ESIMS m/z: 465 [M+NH4]+. HRESIMS m/z:
465.1487 [M+NH4]+, calc. for C21H21NO10+NH4, m/
z 465.1509. 1H NMR (Me2CO-d6+D2O): ꢀ 7.53 (2H, dd
J=2, 7.5 Hz, H-4, 8), 7.41–7.44 (3H, m, H-5–7), 7.17
(2H, s, H-200, 600), 5.82 (1H, s, H-2), 4.59 (1H, dd, J=2,
12 Hz glc H-60), 4.40 (1H, d, J=7.5 Hz, glc H-10), 4.36
(1H, dd, J=6, 12 Hz, glc H-60), 3.57 (1H, ddd, J=2, 6,
10 Hz, glc H-50), 3.48 (1H, t, J=10 Hz, glc H-40), 3.39
(1H, t, J=9 Hz, glc H-30), 3.36 (1H, dd, J=7.5, 9 Hz,
glc H-20). 13C NMR (Me2CO-d6+D2O): ꢀ 167.1 (C-700),
146.0 (2C, C-300, 500), 138.9 (C-400), 134.4 (C-3), 130.5 (C-
6), 129.8 (2C, C-5, 7), 128.5 (2C, C-4, 8), 121.4 (C-100),
118.8 (C-1), 109.8 (2C, C-200, 600), 101.9 (glc C-10), 77.4
(glc C-30), 75.3 (glc C-50), 74. 2 (glc C-20), 70.8 (glc C-40),
68.2 (C-2), 64.3 (glc C-60).
3.4. Quercetin 3-(600-O-trans-caffeoyl)-ꢂ-d-
galactopyranoside (3)
A yellow powder, UV lmax MeOH nm (log "): 366 sh
(4.15), 335 (4.32), 301 (4.20), 267.0 sh (4.24), 253.5 (4.32);
MeOH+AlCl3: 440 (426), 354.5 (4.21), 303 sh (4.09),
2.74.5 (4.37); MeOH+AlCl3+HCl: 405 (4.11), 333.0
(4.25), 302 sh (4.20), 271.5 (4.35). ESIMS m/z: 627
3.7. Enzymatic hydrolysis of 8
An aqueous solution of 8 (4.1 mg mlÀ1) was incubated
ꢀ
at 37 C with tannase prepared from Aspergillus niger
(Yoshida et al., 1989), and the progress of the reaction
was followed by HPLC (RP-2) until the starting mate-
rial disappeared. After 18 h, prunasin and gallic acid
were detected. Prunasin was isolated by preparative
HPLC (RP-2) and identified by co-chromatography
with an authentic sample, and by comparing its optical
1
[M+H]+. H NMR (DMSO-d6): ꢀ 12.61 (1H, s, 5-OH),
7.65 (1H, dd, J=1.5, 8.5 Hz, H-60), 7.50 (1H, d, J=1.5 Hz,
H-20), 6.80 (1H, d, J=8.5 Hz, H-50), 6.36 (1H, d, J=1.5
Hz, H-8), 6.15 (1H, d, J=1.5 Hz, H-6) (quercetin moiety),
5.39 (1H, d, J=8 Hz, H-100), 4.10 (1H, dd, J=4.5, 11.5 Hz,
H-600), 4.04 (1H, dd, J=7.5, 11.5 Hz, H-600), 3.67 (1H, m,
H-500), 3.66 (1H, d, J=3 Hz, H-400), 3.56 (1H, br t, J=8.5
Hz, H-200), 3.42 (1H, dd, J=3, 10 Hz, H-300) (galactose
moiety), 7.30 (1H, d, J=16 Hz, H-7000), 6.96 (1H, br s, H-
2000), 6.81 (1H, d, J=8 Hz, H-5000), 6.74 (1H, br d, J=8 Hz,
H-6000), 6.04 (1H, d, J=16 Hz, H-8000) (caffeoyl moiety).
1
rotation and H NMR spectrum with those reported in
the literature.
Prunasin: [a]D À26.0ꢀ (c 0.5, MeOH) Lit. [a]D À30.1ꢀ
(Seigler, 1975). 1H NMR (Me2CO-d6+D2O): ꢀ 7.60
(2H, dd, J=1, 8 Hz, H-4, 8), 7.45–7.49 (3H, m, H-5-7),
5.95 (1H, s, H-2), 4.38 (1H, d, J=7.5 Hz, glc H-10), 3.86
(1H, dd, J=2.5, 12 Hz, glc H-60), 3.66 (1H, dd, J=6, 12
Hz, glc H-60), 3.27–3.33 (4H, m, glc H-20-50).
3.5. 4-O-(60-O-Galloyl-ꢂ-d-glucopyranosyl)-cis-p-
coumaric acid (7)
3.8. Benzyl 60-O-galloyl-ꢂ-d-glucopyranoside (9)
A white amorphous powder, [a]D À14.3ꢀ (c 1.1,
MeOH). UV lmax MeOH nm (log "): 269 (3.49). ESIMS
m/z: 501 [M+Na]+. HRESIMS m/z: 501.0992
A white amorphous powder, [a]D À29.4ꢀ (c 1.7,
MeOH). UV lmax MeOH nm (log "): 272 (3.68). ESIMS
m/z: 440 [M+NH4]+. HRESIMS m/z: 440.1555
[M+NH4]+, calc. for C20H22O10+NH4, m/z 440.1557.
1H NMR (Me2CO-d6 +D2O): ꢀ 7.36 (2H, dd, J=1.5,
8.5 Hz, H-2, 6), 7.28 (2H, ddd, J=1.5, 7.0, 8.5 Hz, H-3,
5), 7.24 (1H, dt, J=1.5, 7 Hz, H-4), 7.16 (2H, s, galloyl),
4.82, 4.61 (each 1H, d, J=12 Hz, H-7), 4.57 [1H, dd,
J=2, 12 Hz, glc H-60], 4.40 (1H, d, J=8 Hz, glc H-10),
4.37 (1H, dd, J=6, 12 Hz, glc H-60), 3.29 (1H, dd, J=8,
9 Hz, glc H-20), 3.42 (1H, t, J=9 Hz, glc H-30), 3.44
(1H, t, J=9 Hz, glc H-40), 3.58 (1H, ddd, J=2, 6, 9 Hz,
glc H-50). 13C NMR (Me2CO-d6 +D2O) : ꢀ 167.0 (C-
700), 146.0 (2C, C-300, 500), 138.9 (C-1), 138.8 (C-400), 128.9
(2C, C-3, 5), 128.7 (2C, C-2, 6), 128.2 (C-4), 121.6 (C-
1
[M+Na]+, calc. for C22H22O12+Na, m/z 501.1009. H
NMR (Me2CO-d6+D2O): ꢀ 7.71 (2H, d, J=8.5 Hz, H-
2, 6), 7.13 (2H, s, H-200, 600), 7.04 (2H, d, J=8.5 Hz, H-3,
5), 6.84 (1H, d, J=12.5 Hz, H-7), 5.83 (1H, d, J=12.5
Hz, H-8), 5.03 (1H, d, J=7.5 Hz, glucose (glc) H-10),
3.49–3.57 (3H, overlapped with HDO, glc H-20–40), 4.63
(1H, dd, J=2, 12 Hz, glc H-60), 4.28 (1H, dd, J=8, 12
Hz, glc H-60). 13C NMR (Me2CO-d6+D2O): ꢀ 167.9 (C-
9), 166.9 (C-700), 159.2 (C-4), 146.0 (2C, C-300, 500), 142.9
(C-7), 138.8 (C-400), 132.9 (2C, C-2, 6), 129.9 (C-1),
121.5 (C-100), 118.7 (C-8), 116.6 (2C, C-3, 5), 109.9 (2C,
C-200, 600), 101.5 (glc C-10), 77.7 (glc C-30), 75.1 (glc C-50),
74.5 (glc C-20), 71.1 (glc C-40), 64.5 (glc C-60).

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J.H. Isaza et al. / Phytochemistry 58 (2001) 321–327
100), 109.8 (2C, C-200, 600), 102.9 (glc C-10), 77.0 (glc C-30),
75.0 (glc C-50), 74.7 (glc C-20), 71.2 (glc C-40), 70.9 (C-7),
64.5 (glc C-60).
3.37 (6H, s, 2 ꢁ CH3OCO–), 3.87, 3.90 (6H each s, 4 ꢁ
CH3O–).
3.10.2. Penta-O-methylquercetin
3.9. Monochaetin (10)
1H NMR (CDCl3): ꢀ 7.72 (1H, d, J=2.0 Hz, H-20),
7.70 (1H, dd, J=2, 9, Hz, H-60), 6.98 (1H, d, J=9.0 Hz,
H-50), 6.51 (1H, d, J=2.5 Hz, H-8), 6.35 (1H, d, J=2.5
Hz, H-6), 3.97, 3.96, 3.96, 3.91, 3.88 (3H each, s, 5 ꢁ
CH3O–).
A yellow amorphous powder, [a]D +25.0ꢀ (c 1.0,
MeOH). UV lmax MeOH nm (log "): 358 (4.61), 286 sh
(4.46), 267 sh (4.67), 258 (4.71); MeOH+AlCl3: 430
(471), 339 sh (4.21), 298 sh (4.50), 275 (4.84); MeO-
H+AlCl3+HCl: 402 (4.59), 367 sh (4.50), 198 sh (4.38),
271 (4.78); MeOH+AcONa: 273.0 (4.79), 321.0 (4.46),
394.8 (4.57); MeOH+AcONa+H3BO3: 260.5 (4.79),
291.5 (4.51), 377.7 (4.62). ESIMS m/z: 1253 [M+H]+,
951 [M+H-quercetin (Q)]+, 645 [M+H-2Q]+, 303
[Q+H]+. HRESIMS m/z: 1253.2689 [M+H]+, calc.
Acknowledgements
This work was supported in part by a Grant-in-Aid
(No. 09672143) for Scientific Research from the Ministry
of Education, Culture, Sports, Science and Technology
of Japan. The authors are grateful to the SC-NMR
Laboratory of Okayama University for the NMR mea-
surements. One of us (J.H.I.) thanks Universidad Tec-
nologica de Pereira in Colombia for study commission.
1
for C60H52O30+H, m/z 1253.2622. H NMR (DMSO-
d6, 50 ꢀC): ꢀ 12.56 (2H, s, 5-OH), 6.19, 6.20 (1H each, d,
J=2.0 Hz, H-6), 6.35, 6.37 (1H each, d, J=2.0 Hz, H-
8), 7.51, 7.52 (1H each, d, J=2 Hz, H-20), 6.79, 6.81 (1H
each, d, J=8.5 Hz, H-50), 7.58, 7.59 (1H each, dd, J=2,
8.5 Hz, H-60) (quercetin moieties), 5.24, 5.26 (1H each,
d, J=7.5 Hz, H-100), 3.52, 3.54 (1H each, dd, J=7.5, 9.5
Hz, H-200), 3.29, 3.32 (1H each, dd, J=3, 9.5 Hz, H-300),
3.40 (2H, br d, J=3 Hz, H-400), 3.11, 3.12 (1H each, m,
H-500), 3.52 (1H, dd, J=5, 10.5 Hz, H-600), 3.62 (1H, dd,
J=7, 11.5 Hz, H-600), 3.84 (1H, dd, J=6.5, 10.5 Hz, H-
600), 3.71 (1H, dd, J=5, 11.5 Hz, H-600) (galactose moi-
eties), 6.52, 6.54 (1H each, d, J=2.0 Hz, H-2, 20), 6.56,
6.59 (1H each, d, J=8.0 Hz, H-5, 50), 6.25, 6.30 (1H
each, dd, J=2, 8 Hz, H-6, 60), 3.87, 3.89 (1H each, ddd,
J=2, 7, 10.5 Hz, H-7, 70), 3.46, 3.54 (1H each, ddd,
J=2, 7, 10.5 Hz, H-8, 80) (m-truxinoyl moiety). 13C
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