Complete 1H and 13C NMR assignments of a series of pergalloylated tannins

Full text of DOI:10.1002/mrc.4328

Letter - spectral assignment
Received: 3 June 2015
Revised: 31 July 2015
Accepted: 3 August 2015
Published online in Wiley Online Library: 9 September 2015
(wileyonlinelibrary.com) DOI 10.1002/mrc.4328
1
13
Complete H and C NMR assignments of a
series of pergalloylated tannins
Serge Lavoie,a Michael Ouellet,a Pierre-Yves Fleury,a Charles Gauthier,a,b
Jean Legaulta and André Pichettea*
were transferred to carbon through HSQC experiments. The
Introduction
anomeric configurations of derivatives 1, 3–6, and 8 were deter-
3
Tannins are secondary metabolites widely distributed in the plant
kingdom.[1] A common feature of tannins is their phenolic units,
which can be linked together to form highly diverse chemical
structures.[2] Because these compounds constitute an important
fraction of the food and beverage ingested,[3] they have been thor-
oughly studied for their biological effects.[4–6] Recently, we have
performed a phytochemical study on Cornus canadensis, an abun-
dant flowering plant growing wild in North America and giving ed-
ible fruits.[7] A preliminary bioactivity screening was performed and
revealed that an extract from C. canadensis was active toward Her-
pes simplex virus type 1.[8] Following bioassay-guided fractionations,
hydrolyzable tannins were identified.[9] One of these compounds,
namely, 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (PGG), has
been the subject of several pharmaceutical studies as recently
reviewed by Zhang.[10] The biological and medicinal properties of
PGG are diverse and include anticancer, antioxidant, antimutagenic,
anti-inflammatory, anti-allergic, hypocholesterolemic, anticoa-
gulation, antinephrolithiasis, anticonvulsion, antiviral, and antibac-
terial activities. Furthermore, a series of PGG analogs were
synthesized and found to be an optimal scaffold to stimulate glu-
cose transport in adipocytes.[11] Some of these compounds were
also prepared in our laboratory in order to assess their antiherpetic
activities. Because these analogs were only partially characterized
mined from the JH1,H2 coupling constants. While it is generally
accepted that axial protons are at a lower frequency compared with
equatorial protons,[13] some atypical differences were observed after
careful examination of 1H chemical shifts. For instance, D-mannose 2β
(δH 6.49, vs 6.33 for α anomer) and L-rhamnose 7β (δH 6.36, vs 6.22 for
α anomer) showed deshielded axial anomeric protons. As the
anomeric configurations of these two saccharides are not trivial to
1
determine because of the small H–1H coupling for both anomers,
their irregular chemical shifts could have led to incorrect assign-
ments. The anomeric configurations of compounds 2 and 7 were
thus determined with the help of 1JC1,H1 measured in the 1H dimen-
sion of a coupled heteronuclear single-quantum correlation (HSQC)
experiment (Table 5).[14,15]
In another case, H-5ax of L-ribose 5α was found at a higher fre-
quency compared with H-5eq (δH 4.29 and 4.07, respectively). More-
over, the coupling constant of H-5ax with H-4 (J = 8.5 Hz) was found
significantly below the expected value of 10.7Hz for axial–axial
coupled protons.[16] This atypical behavior of derivative 5α could
4
be explained by a time-averaging spectrum of the C1 conforma-
tion with the dominant 1C4 conformation, the latter being depicted
in Fig. 1. In addition, the irregular axial/equatorial chemical shift dif-
ferences could be attributed to the magnetic anisotropy of galloyl
units. The arabinose derivative 6α (3 JH1,H2 = 6.2Hz) also exhibited
a conformational equilibrium between 4C1 and 1C4 based on a
smaller than average coupling constant (mean 3 JH1,H2 = 8.1 Hz).
The four or five galloyl groups were first assigned with the help of
HMBC. Indeed, the H-2′,6′ protons of each galloyl unit correlated
with C-1′, C-3′,5′, C-4′, and C-7′. To discriminate each group of car-
bon, semi-selective HSQC, semi-selective HMBC, or semi-selective
long-range optimized HSQC[17] were acquired with 0.1–1 KHz F1
spectral width (Fig. 2). Once all the galloyl carbons were assigned,
including the carbonyl function, their positions on the sugar core
1
by NMR,[11] we would like to report herein the complete H and
13C assignments of pergalloylated D-glucose (1), D-mannose (2), D-
galactose (3), D-xylose (4), L-ribose (5), L-arabinose (6), L-rhamnose
(7), and D-fucose (8) by using a combination of one-dimensional
and two-dimensional NMR experiments.
Results and discussion
The synthesis of the pergalloylated sugars 1–8 (Fig. 1) was per-
formed in a two-step process via a modified Steglich esterification
followed by a catalytic hydrogenolysis. HPLC separations of the
anomeric mixtures provided 16 compounds, eight α-configured
as well as eight β-configured derivatives, which were fully charac-
terized by NMR spectroscopy (Tables 1–4, see Supporting informa-
tion for spectra). It is worth to mention that α and β sugars are
named according to the relative position of the oxygen functions
at the reference carbon and anomeric position.[12] By convention,
in the Fischer projection, the anomer having the same orientation
at these two positions is called α and vice versa. The proton signals
of the sugar cores were assigned on the basis of 1H–1H COSY and
*
Correspondence to: André Pichette, Chaire de Recherche sur les Agents
Anticancéreux d’Origine Naturelle, Laboratoire LASEVE, Département des Sciences
Fondamentales, Université du Québec à Chicoutimi, 555 boul. de l’Université,
Chicoutimi, Québec, G7H 2B1, Canada. E-mail: andre_pichette@uqac.ca
a Chaire de Recherche sur les Agents Anticancéreux d’Origine Naturelle, Laboratoire
LASEVE, Département des Sciences Fondamentales, Université du Québec à
Chicoutimi, 555 boul. de l’Université, Chicoutimi, Québec, G7H 2B1, Canada
b Institut de Chimie IC2MP, Université de Poitiers, CNRS-UMR 7285, Équipe Synthèse
Organique, 4 rue Michel Brunet, 86073, Poitiers Cedex-9, France
Magn. Reson. Chem. 2016, 54, 168–174
Copyright © 2015 John Wiley & Sons, Ltd.

1H and 13C NMR of pergalloylated tannins
were determined from the respective oxymethine proton HMBC
correlation with a carbonyl of one galloyl unit.
Compound 6α was a complicated case. Indeed, protons H-2 and
H-3 of the sugar core were perfectly overlapped at δH 5.69. On the
semi-selective HMBC, it was possible to distinguish the correlation
between H-1 and the corresponding galloyl carbonyl at δC 164.36.
However, the correlation of H-4 was not visible and those of H-2
and H-3 were unusable. Thus, another strategy was used consisting
in a sequence of one-dimensional selective rotating frame NOE
spectroscopy (ROESY) experiments (Fig. 3). The selective irradiation
of G-1 (H-2′,6′ of galloyl unit on O-1) at δH 6.94, followed by a mixing
time of 200 ms, resulted in a spectrum with correlation at δH 6.87,
which was assigned to G-2. Three other ROESY spectra were ac-
quired in order to successively assign G-2 to G-4. Once the H-2′,6′
Figure 1. Structures of tannins 1–8.
1
Table 1. H NMR spectral data (400 MHz)a of derivatives 1–4 in dimethyl sulfoxide-d6
No.b
1α
1β
2α
2β
1
2
3
4
5
6
6.63 d (3.6)
6.39 d (8.3)
6.33 d (2.2)
5.62 dd (2.8, 2.2)
5.72 dd (10.0, 2.8)
5.66 dd (10.4, 10.0)
4.48 dd (10.4, 6.7)
4.43 br d (11.4)
4.35 dd (11.4, 6.7)
7.15 s
6.49 s
5.42 dd (10.0, 3.6)
5.99 t (10.0)
5.60 t (10.0)
4.51 br d (10.0)
4.33 br s
5.44 dd (10.2, 8.3)
5.97 dd (10.2, 9.2)
5.46 dd (10.5, 9.2)
4.60 br d (10.5)
4.32 br s
5.78 d (3.2)
5.81 dd (9.8, 3.2)
5.50 dd (10.3, 9.8)
4.47 dd (10.3, 7.8)
4.41 br d (12.0)
4.30 dd (12.0, 7.8)
6.83 s
G-1
G-2
G-3
G-4
G-6
7.11 s
6.80 s
6.84 s
6.90 s
7.01 s
6.93 s
6.83 s
6.78 s
6.86 s
6.99 s
7.03 s
7.05 s
6.79 s
6.74 s
6.98 s
6.93 s
6.93 s
6.95 s
No.
1
3α
3β
4α
4β
6.66 d (3.6)
6.32 d (8.2)
6.51 d (3.8)
6.17 d (8.1)
2
5.64 dd (10.8, 3.6)
5.83 dd (10.8, 3.3)
5.88 d (3.3)
5.68 dd (10.3, 8.2)
5.80 dd (10.3, 3.4)
5.71 d (3.4)
5.43 dd (10.3, 3.8)
5.90 t (10.3)
5.43 dd (9.6, 8.1)
5.85 t (9.6)
3
4
5.37 td (10.3, 5.9)
4.14 dd (11.1, 5.9)
3.83 dd (11.1, 10.3)
—
5.26 td (9.6, 5.6)
4.19 dd (11.6, 5.6)
3.91 dd (11.6, 9.6)
—
5
4.81 dd (6.7, 6.2)
4.80 t (6.4)
6
4.29 dd (10.4, 6.2)
4.18 dd (10.4, 6.7)
7.10 s
4.30 dd (11.7, 6.4)
4.22 dd (11.7, 6.4)
6.95 s
G-1
G-2
G-3
G-4
G-6
7.05 s
6.78 s
6.87 s
6.89 s
—
6.90 s
6.82 s
6.82 s
6.86 s
—
6.78 s
6.84 s
6.76 s
6.74 s
7.01 s
7.01 s
6.88 s
6.93 s
aδH mult. (J in Hz).
bG-1 to G-6 represent H-2,6 of gallic acid positioned on the corresponding sugar hydroxy.
1
Table 2. H NMR spectral data (400 MHz)a of derivatives 5–8 in dimethyl sulfoxide-d6
No.b
5α
5β
6α
6β
1
2
3
4
5
6.38 d (3.9)
6.24 d (8.1)
6.12 d (6.2)
5.69 m
6.57 d (3.6)
5.55 t (3.9)
5.36 dd (8.1, 3.0)
5.98 t (3.0)
5.64 dd (10.8, 3.6)
5.78 dd (10.8, 3.4)
5.70 d (3.4)
5.94 t (3.9)
5.69 m
5.36 dt (8.5, 3.9)
4.29 dd (11.7, 8.5)
4.03 dd (11.7, 3.9)
5.39 m
5.56 br s
4.22 dd (10.8, 5.1)
4.07 t (10.8)
4.26 br d (12.7)
4.10 br d (12.7)
4.30 br d (13.3)
4.00 br d (13.3)
(Continues)
Magn. Reson. Chem. 2016, 54, 168–174
Copyright © 2015 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/mrc

S. Lavoie et al.
Table 2. (Continued)
No.b
5α
5β
6α
6β
G-1
G-2
G-3
G-4
7.02 s
6.88 s
7.03 s
6.86 s
6.95 s
6.78 s
7.02 s
6.81 s
6.94 s
6.87 s
6.78 s
7.02 s
7.07 s
6.81 s
6.79 s
7.02 s
No.
1
7α
6.22 br s
7β
8α
8β
6.36 s
6.57 d (3.7)
5.59 dd (10.9, 3.7)
5.78 dd (10.9, 3.4)
5.64 d (3.4)
4.59 q (6.5)
1.12 d (6.5)
7.07 s
6.18 d (8.0)
5.62 dd (10.4, 8.0)
5.68 dd (10.4, 3.4)
5.48 d (3.4)
4.48 q (6.4)
1.14 d (6.4)
6.93 s
2
5.59 d (3.6)
5.63 dd (10.0, 3.6)
5.47 t (10.0)
4.21 dq (10.0, 6.2)
1.26 d (6.2)
7.12 s
5.77 d (3.2)
5.65 dd (9.9, 3.2)
5.37 t (9.9)
4.13 dq (9.9, 6.0)
1.27 d (6.0)
6.83 s
3
4
5
6
G-1
G-2
G-3
G-4
7.02 s
7.05 s
6.79 s
6.83 s
6.77 s
6.74 s
6.76 s
6.73 s
6.95 s
6.91 s
7.02 s
7.01 s
aδH mult. (J in Hz).
bG-1 to G-4 represent H-2,6 of gallic acid positioned on the corresponding sugar hydroxy.
Table 3. 13C NMR spectral data (100 MHz) of derivatives 1–4 in dimethyl sulfoxide-d6
Pos.
1α
1β
2α
2β
3α
3β
4α
4β
Sugar
1
2
3
4
89.22
70.09
69.71
67.62
70.52
61.50
91.96
70.82
72.19
67.98
72.40
61.68
91.04
68.37
69.42
65.72
71.30
63.20
91.33
68.51
70.75
66.14
72.97
63.54
89.35
67.01
67.62
67.62
69.26
61.23
92.18
68.19
70.91
67.71
71.78
61.60
89.22
69.85
69.14
68.57
60.74
–
92.53
70.39
71.63
69.17
62.89
–
5
6
G-1
1
2,6
3,5
4
118.12
109.35
146.07
139.97
164.29
117.60
109.28
145.92
139.92
164.21
117.87
109.29
145.98
139.82
163.43
117.72
109.02
145.65
139.47
163.55
117.84
109.18
145.81
139.63
164.06
117.52
109.18
145.84
139.81
164.23
117.99
109.06
145.89
139.68
164.21
117.55
109.01
145.68
139.60
164.16
7
G-2
1
2,6
3,5
4
117.97
109.07
145.74
139.57
165.23
118.18
109.05
145.71
139.41
164.86
118.27
109.16
145.83
139.41
164.71
118.37
109.11
145.67
139.13
165.03
117.72
108.70
145.54
139.30
165.16
118.21
108.83
145.63
139.25
164.86
117.87
108.88
145.57
139.30
165.03
118.04
108.79
145.50
139.11
164.54
7
G-3
1
2,6
3,5
4
118.36
109.01
145.67
139.28
165.26
118.35
108.97
145.63
139.18
165.08
118.22
108.86
145.59
139.26
165.20
118.11
108.71
145.48
139.12
164.92
118.15
108.70
145.48
139.09
165.06
118.41
108.83
145.54
139.10
165.09
118.33
108.88
145.54
139.07
165.12
118.26
108.80
145.46
138.94
164.87
7
G-4
1
2,6
3,5
4
118.22
109.19
145.79
139.43
164.68
118.32
109.14
145.74
139.37
164.72
118.04
109.10
145.73
139.41
165.03
118.02
108.95
145.62
139.31
165.18
118.07
108.85
145.76
139.25
164.69
118.38
108.95
145.85
139.33
164.94
118.12
108.97
145.66
139.21
164.95
118.19
108.87
145.57
139.11
164.96
7
G-6
1
2,6
3,5
4
119.22
109.07
145.82
139.02
165.71
119.15
109.01
145.80
139.03
165.69
118.92
108.92
145.67
138.92
165.78
118.82
108.79
145.62
138.83
165.73
118.58
108.77
145.57
138.89
165.34
118.74
108.90
145.73
139.05
165.54
—
—
—
—
—
—
—
—
—
—
7
wileyonlinelibrary.com/journal/mrc
Copyright © 2015 John Wiley & Sons, Ltd.
Magn. Reson. Chem. 2016, 54, 168–174

1H and 13C NMR of pergalloylated tannins
Table 4. 13C NMR chemical shifts for derivatives 5–8 in dimethyl sulfoxide-d6
Pos.
5α
5β
6α
6β
7α
7β
8α
8β
Sugar
1
89.13
67.04
67.33
66.33
59.13
—
90.72
68.61
67.91
66.56
62.26
—
92.75
68.34
70.83
68.36
65.15
—
89.79
67.17
67.28
68.50
62.90
—
90.92
68.54
69.38
70.06
68.98
17.68
91.24
65.61
70.97
70.59
68.87
17.67
89.49
66.99
67.96
70.54
67.62
15.92
92.17
68.06
71.19
70.35
69.91
15.87
2
3
4
5
6
G-1
1
118.58
109.39
145.66
139.33
165.03
117.54
108.98
145.73
139.68
164.37
117.66
109.10
145.77
139.70
164.36
117.86
109.01
145.78
139.63
164.23
117.93
109.14
145.90
139.68
163.55
117.98
109.09
145.69
139.49
163.80
118.07
109.07
145.80
139.52
164.25
117.63
109.03
145.72
139.61
164.31
2,6
3,5
4
7
G-2
1
118.58
109.12
145.50
139.07
165.15
118.01
108.72
145.55
139.20
164.52
118.28
108.82
145.60
139.18
164.81
117.72
108.68
145.51
139.32
165.15
118.24
109.02
145.74
139.32
164.60
118.61
109.18
145.71
139.16
165.15
117.85
108.70
145.53
139.25
165.23
118.23
108.72
145.53
139.10
164.79
2,6
3,5
4
7
G-3
1
118.99
109.26
145.55
138.90
165.70
118.36
108.92
145.69
139.10
164.80
118.44
108.82
145.52
139.07
165.09
118.17
108.68
145.46
139.10
165.04
118.24
108.76
145.49
139.13
165.20
118.38
108.80
145.52
139.10
165.05
118.27
108.65
145.47
139.05
165.09
118.39
108.72
145.45
138.98
165.02
2,6
3,5
4
7
G-4
1
118.67
108.99
145.57
138.99
164.98
118.34
108.82
145.55
139.07
164.78
118.86
108.91
145.74
139.10
165.05
118.55
108.79
145.66
139.05
164.85
118.24
108.87
145.67
139.19
165.04
118.49
108.91
145.68
139.16
165.22
118.30
108.81
145.74
139.12
165.19
118.50
108.84
145.74
139.11
165.33
2,6
3,5
4
7
1
Table 5. JC1, H1 (Hz) for derivatives 1–8 in dimethyl sulfoxide-d6
Compound
α
β
1
2
3
4
5
6
7
8
181.0
179.7
177.7
177.7
174.4
170.3
177.7
179.1
170.3
167.0
171.5
170.8
170.0
179.8
166.3
169.0
Figure 2. HMBC (a) and selective HMBC (b) of 1,2,3,4,6-penta-O-galloyl-β-D-
glucopyranoside (1β). (a) Expansion of the HMBC recorded with a spectral
width of 12 KHz in F1. (b) The full semi-selective HMBC recorded with a
spectral width of 0.1 KHz in F1 and centered at 145.9 ppm.
protons were ascribed, the chemical shifts of the other positions
were readily determined.
In the course of the galloylation of galactose and ribose, a third
compound was isolated from both reaction mixtures (Fig. 4). Care-
ful examination of 1H–1H double-quantum filtered (DQF)-COSY sug-
gested that these compounds were the furanose forms of their
respective sugars. Indeed, H-4 of 1,2,3,5,6-penta-O-galloyl-β-D-
galactofuranose (3f) showed a shielded signal at δH 4.60 in compar-
ison with H-4 signals of compounds 3α and 3β at δH 5.88 and 5.71,
respectively, indicating that the galloyl group was at O-5 rather
than at O-4 (Table 6). Moreover, H-1 showed an HMBC correlation
with C-4 further supporting the furanoside form of 3f. The β-
configuration was determined on the basis of the 3JH1,H2 coupling
Magn. Reson. Chem. 2016, 54, 168–174
Copyright © 2015 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/mrc

S. Lavoie et al.
Table 6. 1H and 13C NMR spectroscopic data for derivatives 3f and 5f in
dimethyl sulfoxide-d6
Pos.
3f
5f
13C
1H
13C
1H
Sugar
1
2
3
4
5
93.04
75.91
73.29
77.98
71.60
6.57 d (4.7)
98.51
6.37 br s
5.68 dd (7.3, 4.7) 73.95
5.66 br d (5.4)
5.59 t (5.4)
4.65 m
5.97 t (7.3)
4.59 t (7.3)
71.35
79.69
5.57 dd (7.3, 3.2) 65.70
4.65 m
4.23 dd (12.5, 8.9)
—
6
62.23
4.51 dd (12.3, 3.2)
4.37 dd (12.3, 7.3)
G-1
1
118.45
109.10
145.69
139.30
164.49
—
118.09
109.05
145.76
139.46
164.15
—
7.03 s
—
2,6
3,5
4
7.00 s
6.90 s
7.01 s
6.89 s
6.83 s
—
—
—
—
7
—
G-2
1
117.90
109.00
145.67
139.30
165.07
—
117.99
108.91
145.66
139.20
164.50
—
6.95 s
—
2,6
3,5
4
—
—
—
—
Figure 3. One-dimensional selective rotating frame NOE spectroscopy
(200 ms mixing time) of 6α with irradiation of H-2′,6′ for G-1 (b), G-2 (c), G-
3 (d), and G-4 (e). The 1D 1H spectrum (a).
7
—
G-3
1
118.09
109.21
145.70
139.33
165.09
—
118.04
108.91
145.60
139.15
165.03
—
6.90 s
—
2,6
3,5
4
—
—
—
—
7
—
G-5
1
118.85
109.00
145.65
138.97
164.95
—
118.75
108.74
145.64
138.80
165.57
—
6.97 s
—
2,6
3,5
4
—
—
—
—
7
—
G-6
1
118.72
108.78
145.57
138.85
165.59
—
—
—
—
—
—
—
—
—
—
—
2,6
3,5
4
—
—
—
7
Conclusion
In summary, a series of α-configured and β-configured pergalloylated
tannins were synthesized, and their structures fully characterized by
NMR using a combination of one-dimensional and two-dimensional
experiments. Semi-selective HMBC, one-dimensional selective
ROESY, and 1H–1H DQF-COSY were useful in order to assign some dif-
ficult cases such as compounds 6α and furanoses 3f and 5f.
Figure 4. Structures of furanoses 3f and 5f.
constant of 4.7 Hz.[18] 1,2,3,5-Tetra-O-galloyl-β-L-ribofuranoside (5f)
was assigned based on the same approach (a low-frequency H-4
signal at δH 4.65 and an HMBC correlation from H-1 to C-4). A broad
singlet was observed on the 1H NMR spectrum, which was
consistent with the β-configured ribofuranose. In comparison,
Experimental
General procedure for the synthesis of pergalloylated tannins
1–8
3
Houseknecht et al. measured the JH1,H2 coupling constant for
methyl α- and methyl β-ribofuranoses and obtained values of 4.4
To a solution of the free sugar (1.0equiv) suspended in CH2Cl2
(120mlmmolꢀ1) were added 4-dimethylaminopyridine (8.6equiv.),
and 1.3Hz, respectively.[19]
wileyonlinelibrary.com/journal/mrc
Copyright © 2015 John Wiley & Sons, Ltd.
Magn. Reson. Chem. 2016, 54, 168–174

1H and 13C NMR of pergalloylated tannins
N,N′-dicyclohexylcarbodiimide (9.1equiv.), and 3,4,5-tri(benzyloxy)
benzoic acid[11] (7.3 equiv). The mixture was stirred for 18h under
reflux. The mixture was cooled to room temperature, filtered, and
the solvents were concentrated under reduced pressure. The
residue was purified by silica gel flash chromatography
(hexanes/EtOAc 8 : 2) to give an inseparable α/β mixture of the
pertribenzylgalloylated sugar. The latter compound was dis-
solved in THF (240 ml mmolꢀ1), and 10% Pd/C was added
(0.1 equiv). The suspension was purged with H2 for 1 h and
stirred under H2 for 15 h (15 psi). Then, the mixture was filtered
over Celite, and the solvents of the filtrate were concentrated
under reduced pressure. The residue was purified by prepara-
tive HPLC (30 → 50% MeOH in H2O for 15 min) to give the
pergalloylated tannins 1–8 as pure α- and β-anomers (8–49%,
over two steps).
1,2,3,4-Tetra-O-galloyl-β-L-rhamnopyranose (7β): Yield = 23%;
25
amorphous solid; ½αꢁD : +32.0 (c = 1.8 in MeOH). 1H and 13C NMR: re-
fer to Tables 2 and 4, respectively.
1,2,3,4-Tetra-O-galloyl-α-D-fucopyranose (8α): Yield = 5%; amor-
25
phous solid; ½αꢁD : +165.7 (c = 0.03 in MeOH). 1H and 13C NMR: refer
to Tables 2 and 4, respectively.
1,2,3,4-Tetra-O-galloyl-β-D-fucopyranose (8β): Yield = 3%; amor-
25
1
phous solid; ½αꢁD : +19.0 (c = 0.4 in MeOH). H and 13C NMR: refer
to Tables 2 and 4, respectively.
Spectra
The 1H and 13C NMR spectra were recorded in DMSO-d6 at 19–20 °C
with a Bruker Avance spectrometer (Bruker BioSpin Corporation,
1
Milton, Canada) working at 400 MHz for H and 100 MHz for 13C
1,2,3,4,6-Penta-O-galloyl-α-D-glucopyranose (1α): Yield = 24%;
NMR, respectively. Chemical shifts are given in the δ-scale and are
referenced to the solvent residual peak (DMSO-d6: δc = 39.52 ppm
and δH = 2.50 ppm). Pulse program of all experiments (1H, 13C,
DEPT-135, DQF-COSY, HSQC, HMBC, sel. HSQC, sel. HMBC) were
taken from the Bruker software library. In the one-dimensional mea-
surements, 64K data points were used for the FID, sweep widths:
6400 and 24000Hz, for 1H and 13C, respectively. The ROESY spectra
were acquired with a 200ms mixing time. For two-dimensional
measurements, sweep width in F2 was adjusted to the observed
resonance, between 1400 to 2800 Hz, and all data points (t2 × t1)
were acquired with 2 K × 256. In F1, linear prediction was applied
to enhance the resolution. The heteronuclear two-dimensional ex-
periments were recorded with a one-bond heteronuclear coupling
value set to 140 Hz and a long-range coupling value set to 10Hz.
The selective HSQC and HMBC were recorded using a Gaussian
shaped inversion or excitation pulse of 1468 and 4244 μs,
respectively.
25
amorphous solid; ½αꢁD : +116.1 (c = 1.3 in MeOH). 1H and 13C NMR:
refer to Tables 1 and 3, respectively.
1,2,3,4,6-Penta-O-galloyl-β-D-glucopyranose (1β): Yield = 25%;
25
amorphous solid; ½αꢁD : +13.9 (c = 1.4 in MeOH). 1H and 13C NMR: re-
fer to Tables 1 and 3, respectively.
1,2,3,4,6-Penta-O-galloyl-α-D-mannopyranose (2α): Yield = 16%;
25
amorphous solid;½αꢁD : ꢀ59.0 (c = 1.2 in MeOH). 1H and 13C NMR: re-
fer to Tables 1 and 3, respectively.
1,2,3,4,6-Penta-O-galloyl-β-D-mannopyranose (2β): Yield = 31%;
25
amorphous solid;½αꢁD : ꢀ80.1 (c = 1.0 in MeOH). 1H and 13C NMR: re-
fer to Tables 1 and 3, respectively.
1,2,3,4,6-Penta-O-galloyl-α-D-galactopyranose (3α): Yield = 11%;
25
amorphous solid; ½αꢁD : +320.7 (c = 0.9 in MeOH). 1H and 13C NMR:
refer to Tables 1 and 3, respectively.
1,2,3,4,6-Penta-O-galloyl-β-D-galactopyranose (3β): Yield = 7%;
25
amorphous solid; ½αꢁD : +170.5 (c = 0.1 in MeOH). 1H and 13C NMR:
refer to Tables 1 and 3, respectively.
Declaration of interest
1,2,3,5,6-Penta-O-galloyl-β-D-galactofuranose (3f): Yield = 6%;
25
amorphous solid; ½αꢁD : +45.4 (c = 0.1 in MeOH). 1H and 13C NMR: re-
The authors report no conflicts of interest.
fer to Table 6.
1,2,3,4-Tetra-O-galloyl-α-D-xylopyranose (4α): Yield = 14%; amor-
25
1
phous solid; ½αꢁD : +67.6 (c = 1.1 in MeOH). H and 13C NMR: refer
Acknowledgement
to Tables 1 and 3, respectively.
This work was supported by the Fonds Québécois de Recherche
Nature et Technologies (PhD fellowship to S. L.).
1,2,3,4-Tetra-O-galloyl-β-D-xylopyranose (4β): Yield= 25%; amor-
25
1
phous solid; ½αꢁD : ꢀ8.3 (c = 2.6 in MeOH). H and 13C NMR: refer
to Tables 1 and 3, respectively.
1,2,3,4-Tetra-O-galloyl-α-L-ribopyranose (5α): Yield = 10%; amor-
25
phous solid; ½αꢁD : ꢀ52.9 (c = 0.8 in MeOH). 1H and 13C NMR: refer
References
to Tables 2 and 4, respectively.
[1] K. Khanbabaee, T. Van Ree. Nat. Prod. Rep. 2001, 18, 641.
[2] S. Quideau, D. Deffieux, C. Douat-Casassus, L. Pouységu. Angew. Chem.
Int. Ed. 2011, 50, 586.
[3] J. Serrano, R. Puupponen-Pimiä, A. Dauer, A. M. Aura, F. Saura-Calixto.
Mol. Nutr. Food Res. 2009, 53, 310.
[4] C. Nepka, E. Asprodini, D. Kouretas. Eur. J. Drug Metab. Pharmacokinet.
1999, 24, 183.
[5] V. Koleckar, K. Kubikova, Z. Rehakova, K. Kuca, D. Jun, L. Jahodar,
L. Opletal. Mini-Rev. Med. Chem. 2008, 8, 436.
[6] P. Buzzini, P. Arapitsas, M. Goretti, B. Turchetti, P. Pinelli, F. Ieri,
A. Romani. Mini-Rev. Med. Chem. 2008, 8, 1179.
[7] C. L. Gucker, in Fire Effects Information System, U.S. Department of
Agriculture, Forest Service, Rocky Mountain Research Station, Fire
Sciences Laboratory, [Online], 2012.
[8] J. Legault, A. Pichette, I. Côté, S. Lavoie. (2015). Use of plant extracts
against herpes simplex virus. World. PCT/CA2014/050693.
[9] Unpublished results.
[10] J. Zhang, L. Li, S. H. Kim, A. E. Hagerman, J. Lü. Pharm. Res. 2009, 26,
2066.
1,2,3,4-Tetra-O-galloyl-β-L-ribopyranose (5β): Yield = 30%; amor-
25
1
phous solid; ½αꢁD : +54.8 (c = 2.2 in MeOH). H and 13C NMR: refer
to Tables 2 and 4, respectively.
1,2,3,5-Tetra-O-galloyl-β-L-ribofuranose (5f): Yield = 5%; amorphous
25
solid; ½αꢁD : +5.5 (c=0.5 in MeOH). 1H and 13C NMR: refer to Table 6.
1,2,3,4-Tetra-O-galloyl-α-L-arabinopyranose (6α): Yield = 29%;
25
amorphous solid; ½αꢁD : +170.1 (c = 2.2 in MeOH). 1H and 13C NMR:
refer to Tables 2 and 4, respectively.
1,2,3,4-Tetra-O-galloyl-β-L-arabinopyranose (6β): Yield = 9%;
25
amorphous solid; ½αꢁD : +78.5 (c = 0.8 in MeOH). 1H and 13C NMR: re-
fer to Tables 2 and 4, respectively.
1,2,3,4-Tetra-O-galloyl-α-L-rhamnopyranose (7α): Yield = 26%;
25
amorphous solid; ½αꢁD : +70.5 (c = 1.5 in MeOH). 1H and 13C NMR: re-
fer to Tables 2 and 4, respectively.
Magn. Reson. Chem. 2016, 54, 168–174
Copyright © 2015 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/mrc

S. Lavoie et al.
[11] Y. Ren, K. Himmeldirk, X. Chen. J. Med. Chem. 2006, 49, 2829.
[12] A. D. McNaught. Pure Appl. Chem. 1996, 68, 1919.
[13] M. Baranac-Stojanović, M. Stojanović. Chem. Eur. J. 2013, 19, 4249.
[14] K. Bock, C. Pedersen. J. Chem. Soc. Perkin Trans. 1974, 2, 293.
[15] S. Uhrinova, D. Uhrin, T. Liptaj, J. Bella, J. Hirsch. Magn. Reson. Chem.
1991, 29, 912.
[18] M. R. Richards, Y. Bai, T. L. Lowary. Carbohydr. Res. 2013, 374, 103.
[19] J. B. Houseknecht, T. L. Lowary, C. M. Hadad. J. Phys. Chem. A 2003,
107, 372.
Supporting Information
[16] C. A. G. Haasnoot, F. A. A. M. de Leeuw, C. Altona. Tetrahedron 1980,
36, 2783.
Additional supporting information may be found in the online ver-
[17] A. Bax, K. A. Farley, G. S. Walker. J. Magn. Reson. Ser. A 1996, 119, 134.
sion of this article at the publisher’s web site.
wileyonlinelibrary.com/journal/mrc
Copyright © 2015 John Wiley & Sons, Ltd.
Magn. Reson. Chem. 2016, 54, 168–174