Syntheses of arabinogalactans consisting of β-(1 → 6)-linked D-galactopyranosyl backbone and α-(1 → 3)-linked L-arabinofuranosyl side chains

Article abstract of DOI:10.1016/j.carres.2004.05.007

Two arabinogalactosyl nonasaccharides, β-D-Galp-(1→6)-[α-L- Araf-(1→3)]-β-D-Galp-(1→6)-β-D-Galp-(1→6) -β-D-Galp-(1→6)-[α-L-Araf-(1→5)-α-L-Araf-(1→3)] -β-D-Galp-(1→6)-β-D-Galp and β-D-Galp-(1→6)-[α-L- Araf-(1→5)-α-L-Araf-(1→3)]-β-D-Galp-(1→6) -β-D-Galp-(1→

Full text of DOI:10.1016/j.carres.2004.05.007

Carbohydrate
RESEARCH
Carbohydrate Research 339 (2004) 1847–1856
Syntheses of arabinogalactans consisting of b-(1 fi 6)-linked
D
-galactopyranosyl backbone and a-(1 fi 3)-linked
L
-arabinofuranosyl side chains
Aixiao Li and Fanzuo Kong*
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085, China
Received 21 April 2004; accepted 12 May 2004
Abstract—Two arabinogalactosyl nonasaccharides, b-
Galp-(1 fi 6)-[a- -Araf-(1 fi 5)-a- -Araf-(1 fi 3)]-b- -Galp-(1 fi 6)-b-
(1 fi 3)]-b- -Galp-(1 fi 6)-b- -Galp-(1 fi 6)-b- -Galp-(1 fi 6)-[a- -Araf-(1 fi 3)]-b-
their 4-methoxyphenyl glycosides with 2,3,4,6-tetra-O-benzoyl-a- -galactopyranosyl trichloroacetimidate (1), 6-O-acetyl-2,3,4-tri-
O-benzoyl-a- -galactopyranosyl trichloroacetimidate (14), 4-methoxyphenyl 3-O-allyl-2,4-di-O-benzoyl-b- -galactopyranoside (2),
4-methoxyphenyl 2,3,4-tri-O-benzoyl-b- -galactopyranoside (5), 2,3,5-tri-O-benzoyl-a- -arabinofuranosyl trichloroacetimidate (8),
and 2,3,5-tri-O-benzoyl-a- -arabinofuranosyl-(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofuranosyl trichloroacetimidate (11), as the key
D
-Galp-(1 fi 6)-[a-
-Galp and b-
-Galp-(1 fi 6)-b-
L
-Araf-(1 fi 3)]-b-
-Galp-(1 fi 6)-[a-
-Galp, were synthesized as
D
-Galp-(1 fi 6)-b-
D
-Galp-(1 fi 6)-b-
D-
L
L
D
D
D
L
-Araf-(1 fi 5)-a-
L
-Araf-
D
D
D
L
D
D
D
D
D
D
L
L
L
synthons. The tetra- (10) and pentasaccharide donor (13), and the tetra- (20) and pentasaccharide acceptor (22) were synthesized
based on these synthons through simple transformations. Coupling of 22 with 10, and coupling of 20 with 13 and subsequent
deacylation gave nonasaccharides 24 and 26, respectively, consisting of b-(1 fi 6)-linked glactopyranosyl backbone and a-(1 fi 3)-
linked arabinofuranosyl side chains of different size.
ꢀ 2004 Elsevier Ltd. All rights reserved.
Keywords: Galactose; Arabinose; Arabinogalactan
1. Introduction
purpurea, which have immunomodulating activity,1a
while a b-(1 fi 6)-linked galactose trisaccharide back-
bone functionalized at 3-OH with at least one a-linked
Arabinogalactans with immunomodulating activity
have been found from certain sources.1 One of the first
arabinogalactans for which an activity on the comple-
ment system was shown was an arabinogalactan from a
hot water extract of the roots of the Chinese herb
Angelica acutiloba.2 Such activity was not found in the
arabinogalactan from larch wood.3 An arabinogalactan
isolated from the roots of Saposhnikova divaricata or
Panex notoginseng had reticuloendothelial system acti-
vating properties.4 The arabinogalactans with b-(1 fi 6)-
linked galactopyranose backbone and a-(1 fi 2)-linked
arabinofuranose side chains may exist in Echinacea
L
-arabinofuranose unit was supposed to be the mini-
mum epitope recognized by the CCRC-M7 antibody.5
Although the presence of 2,6- and 3,6-branched residues
in arabinogalactan is well known, the exact structure of
these saccharides and the function of the arabinofura-
nose side chains remain to be established.
Some examples on the chemical synthesis of the
arabinogalactans consisting of b-(1 fi 6)-linked galac-
topyranose backbones and a-(1 fi 2)-linked arabinof-
uranose side chains have been reported.6 However,
there have been very few papers dealing with the
synthesis of the arabinogalactans consisting of b-
(1 fi 6)-linked galactopyranose backbones and a-
(1 fi 3)-linked arabinofuranose side chains.7 We present
herein convergent syntheses of the two nonasaccharides
* Corresponding author. Tel.: +86-10-62936613; fax: +86-10-629235-
63; e-mail: fzkong@mail.rcees.ac.cn
0008-6215/$ - see front matter ꢀ 2004 Elsevier Ltd. All rights reserved.
doi:10.1016/j.carres.2004.05.007

1848
A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
24 and 26 consisting of b-(1 fi 6)-linked galactose
hexasaccharide backbone with mono-arabinose side
chain at C-3V, a-(1 fi 5)-linked arabinobiose at C-3II,
and mono-arabinose side chain at C-3II, a-(1 fi 5)-
linked arabinobiose at C-3V, respectively.
di-O-benzoyl-b-
from 4-methoxyphenyl tetra-O-acetyl-b-
D
-galactopyranoside (2), was prepared
-galactopy-
D
ranoside by deacetylation, selective 3-O-allylation via
dibutyltin complex,8 6-O-tritylation and benzoylation,
and detritylation. Condensation of 2 with perbenzoyl-
ated galactopyranosyl trichloroacetimidate9 1 afforded
the disaccharide 3, and subsequent oxidative cleavage of
4-methoxyphenyl group and tricholoroacetimidate
formation gave the disaccharide donor 4. Coupling of 4-
2. Results and discussion
As shown in Scheme 1, the syntheses of the tetrasac-
charide donor 10 and the pentasaccharide donor 13 were
readily achieved based on some monosaccharide deriv-
atives. The key synthon, 4-methoxyphenyl 3-O-allyl-2,4-
methoxyphenyl 2,3,4-tri-O-benzoyl-b-D-galactopyrano-
side (5)6i;j with 4 gave the trisaccharide 6, and subsequent
deallylation yielded the trisaccharide acceptor 7. Con-
densation of 7 with 2,3,5-tri-O-benzoyl-a-L-arabinofur-
OBz
O
BzO
BzO
OBz
O
OBz
OH
O
BzO
BzO
3 R1 = OMp, R2 = H
(1) CAN
(2) CCl3CN
O
4 R1 = H, R2 = OC(NH)CCl3
+
AllO
OCCCl3
BzO
NH
OMp
BzO
O
BzO
R1
OBz
AllO
1
2
BzO
OBz
R2
OBz
O
BzO
BzO
BzO
BzO
BzO
BzO
O
O
OH
O
O
BzO
BzO
BzO
BzO
OMp
O
O
O
BzO
O
BzO
BzO
PdCl2
O
OBz
AllO
HO
5
BzO
BzO
O
7
6 (85%)
OMp
BzO
OMp
OBz
OBz
OBz
O
BzO
OCCCl3
NH
O
O
BzO
9 R1 = OMp, R2 = H
BzO
OBz
BzO
(1) CAN
O
10 R1 = H, R2 = OC(NH)CCl3
(2) CCl3CN
BzO
O
O
OBz
O
8
BzO
BzO
OBz
O
R1
BzO
BzO
OBz
BzO
R2
OBz
O
BzO
12 R1 = OMp, R2 = H
OCCCl3
NH
(1) CAN
O
OBz
O
BzO
13 R1 = H, R2 = OC(NH)CCl3
(2) CCl3CN
BzO
BzO
O
O
O
O
BzO
7
+
O
OBz
O
OBz
OBz
OBz
11
BzO
BzO
O
R1
O
BzO
O
OBz
OBz
BzO
R2
BzO
OBz
OAc
O
OAc
O
BzO
BzO
BzO
BzO
15 R1 = OMp, R2 = H
(1) CAN
(2) CCl3CN
5
2
O
16 R1 = H, R2 = OC(NH)CCl3
NH
OCCCl3
14
BzO
BzO
BzO
O
R1
AllO
BzO
R2
BzO
BzO
OAc
O
OAc
BzO
BzO
O
O
O
BzO
BzO
HO
BzO
BzO
O
O
O
O
BzO
PdCl2
AllO
BzO
BzO
BzO
O
O
BzO
BzO
17 (85%)
18 (85%)
OMp
OMp
OBz
OBz
Scheme 1.

A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
1849
OR
O
BzO
BzO
O
BzO
19 R = Ac
20 R = H
1% MeCOCl in
MeOH/CH2Cl2
BzO
O
O
O
+
+
18
18
8
O
BzO
BzO
BzO
OBz
O
BzO
BzO
OMp
OBz
OBz
OR
O
BzO
BzO
O
BzO
21 R = Ac
22 R = H
1% MeCOCl in
MeOH/CH2Cl2
BzO
O
O
O
11
O
OBz
BzO
BzO
O
O
O
OBz
OMp
OBz
OBz
BzO
OBz
OR
O
RO
RO
O
RO
RO
O
O
RO
O
O
23 R = Bz
24 R = H
RO
NH3-MeOH
OR
O
+
22
10
RO
O
RO
OR
OR RO
RO
O
O
RO
RO
O
O
O
O
OR
RO
RO
O
O
RO
O
OMp
OR
OR
OR
RO
OR
O
RO
RO
OR
O
RO
RO
O
O
RO
O
O
OR
RO
O
25 R = Bz
26 R = H
O
O
NH3-MeOH
O
RO
OR
OR
OR RO
RO
RO
O
OR
O
+
20
13
RO
RO
O
O
O
O
OR
RO
RO
O
RO
RO
OMp
OR
OR
Scheme 1 (continued)
anosyl trichloroacetimidate (8),10 followed by oxidative
cleavage of the 1-OMp group and trichloroacetimidate
formation, yielded the tetrasaccharide donor 10, while
as the upstream unit instead of 1. Thus, coupling of 14
with 2, oxidative cleavage of 1-OMp, trichloroacetimi-
date formation, and condensation with 5, subsequent
deallylation gave 18. Reaction of 18 with 8, then selective
deacetylation11 gave the tetrasaccharide acceptor 20,
while reaction of 18 with 11, then selective deacetyl-
ation11 gave the pentasaccharide acceptor 22.
With the tetra- and pentasaccharide building blocks in
hand, the target nonamers were readily obtained. Thus,
coupling of 22 with 10, followed by deacylation with
ammonia in methanol, yielded the nonasaccharide 24,
while coupling of 20 with 13, followed by deacylation,
gave the nonasaccharide 26.
coupling of 7 with 2,3,5-tri-O-benzoyl-a-
L-arabinofur-
anosyl-(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofuranosyl
L
trichloroacetimidate (11),10 followed by oxidative cleav-
age of the 1-OMp group and trichloroacetimidate for-
mation gave the pentasaccharide donor 13. The
precursor 19 of the tetrasaccharide acceptor, and the
precursor 21 of the pentasaccharide acceptor, were pre-
pared in the same way as described for the preparations
of 9 and 12, except that 6-O-acetyl-2,3,4-tri-O-benzoyl-a-
D
-galactopyranosyl trichloroacetimidate (14) was used

1850
A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
In summary, efficient syntheses of arabinogalactans
consisting of a b-(1 fi 6)-linked galactopyranosyl back-
bone and an a- -arabinofuranosyl monomer or (1 fi 5)-
linked dimer side chains attached at C-3 was achieved.
The method can be used for the preparation of a variety
of different arabinogalactans with the similar structures.
and trityl chloride (6.5 g, 23.0 mmol). The mixture was
stirred at 50 ꢁC for 12 h, at the end of which time TLC (2:1
petroleum ether–EtOAc) indicated that the reaction was
complete. The reaction mixture was cooled to 0 ꢁC, then
benzoyl chloride (5.6 mL, 40 mmol) was added dropwise
within 30 min to keep the reaction temperature at 50 ꢁC,
and then the mixture was stirred at 50 ꢁC overnight.
Water (150 mL) was added to the reaction mixture, and
stirring was continued for 30 min. The mixture was ex-
tracted with CH2Cl2 (3 · 100 mL), and the combined ex-
tracts were washed with 1 N HCl and satd aq NaHCO3,
dried (Na2SO4), and concentrated to a syrup that was
subjected to column chromatography (5:1 petroleum
ether–EtOAc as the eluent) to give 4-methoxyphenyl 3-O-
L
3. Experimental
3.1. General methods
Melting points were determined with a ‘Mel-Temp’
apparatus. Optical rotations were determined at 25 ꢁC
with a digital polarimeter. The NMR spectra were re-
corded in CDCl3 with Me4Si as the internal standard or
D2O with EtOH as standard on a Bruker ARX
400 MHz. Mass spectral data were acquired in the po-
sitive-ion mode using a Bruker Biflex III matrix-assisted
laser desorption/ionization time-of-flight (MALDITOF)
mass spectrometer equipped with a 337 nm nitrogen
laser using DHB as matrix and an acceleration voltage
of 19 kV. Elemental analyses were carried out on an
elemental analyzer model 1108 EA. Thin-layer chroma-
tography (TLC) was performed on silica gel HF254 with
detection by charring with 30% (v/v) H2SO4 in MeOH
or in some cases by a UV lamp. Column chromatogra-
phy was conducted by elution of a column (10 · 240 mm,
18 · 300 mm, 35 · 400 mm) of silica gel (100–200 mesh)
with EtOAc–petroleum ether (bp 60–90 ꢁC) as the elu-
ent. Solutions were concentrated at <60 ꢁC under
diminished pressure. Dry solvents were distilled over
CaH2 and stored over molecular sieves.
allyl-2,4-di-O-benzoyl-6-O-trityl-b-
(10 g, 88%) as a solid. To a solution of 4-methoxyphenyl
3-O-allyl-2,4-di-O-benzoyl-6-O-trityl-b- -galactopyrano-
D-galactopyranoside
D
side (10 g, 12.4 mmol) in CH3OH (50 mL)–CH2Cl2
(50 mL) was added CH3COCl (0.1 mL), and the mixture
was stirred at rt for 3 h, at the end of which time TLC (2:1
petroleum ether–EtOAc) indicated that the reaction was
complete. The mixture was neutralized with Et3N, then
concentrated, and the residue was passed through a silica
gel column with 2:1 petroleum ether–EtOAc as the eluent
to give 2 (5.76 g, 87%) as a foamy solid: ½aꢀ +65.4 (c 1.0,
D
CHCl3); 1H NMR (400 Hz, CDCl3): d 8.13–7.25 (m, 10H,
2 PhH), 6.92 (d, 2H, J 9.1Hz, CH3OC6H4O–), 6.83 (d, 2H,
J 9.1Hz, CH3OC6H4O–), 5.87 (d, 1H, J3;4 3.2 Hz, H-4),
5.76 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2), 5.67 (m, 1H,
CH2@CH–CH2O), 5.17–5.05 (m, 2H, CH2@CH–CH2O),
5.03 (d, 1H, J1;2 8 Hz, H-1), 4.25 (m, 1 H, H-5). 4.08–3.95
(m, 2H, CH2@CH–CH2), 3.90 (dd, 1H, J3;4 3.2Hz, J2;3
10.4 Hz, H-3), 3.78 (dd, 1H, H-6), 3.67 (s, 3H, CH3O), 3.60
(dd, 1H, J5;6 6.4Hz, J6;6 12.0Hz, H-6). Anal. Calcd for
C30H30O9: C, 67.41; H, 5.66. Found: C, 67.62; H, 5.59.
3.2. 4-Methoxyphenyl 3-O-allyl-2,4-di-O-benzoyl-b-D-
galactopyranoside (2)
3.3. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-D-galac-
To a solution of 4-methoxyphenyl 2,3,4,6-tetra-O-acetyl-
b- -galactopyranoside (9.08 g, 20.0 mmol) in CH3OH
topyranosyl-(1 fi 6)-3-O-allyl-2,4-di-O-benzoyl-b-
galactopyranoside (3)
D-
D
(100 mL) was added 4.0 M CH3ONa–CH3OH solution
dropwise to pH 10. After stirring the mixture at rt for 5 h,
TLC (5:1 EtOAc–CH3OH) indicated that the reaction
was complete. The reaction mixture was neutralized with
1:10 HOAc–CH3OH, then the mixture was concentrated,
and the residue was purified by column chromatography
(5:1 EtOAc–CH3OH) to give a solid (5.10 g, 18.0 mmol).
To a solution of the solid in CH3OH (100 mL) was added
Bu2SnO (5.22 g, 20.1 mol), and the mixture was heated
under reflux for 2 h, then concentrated to dryness. The
residue was diluted with toluene (200 mL), and then allyl
bromide (17.1 mL, 200 mol) and Bu4NI (7.38 g, 20.0 mol)
were added to the mixture. The reaction mixture was
stirred out at 60 ꢁC for 24 h, TLC (EtOAc) indicated that
the reaction was complete. The reaction mixture was
concentrated, and the residue was diluted with CH2Cl2
(20 mL). To the mixture was added pyridine (100 mL)
A solution of 2 (2.4 g, 4.49 mmol) and 2,3,4,6-tetra-O-
benzoyl-a- -galactopyranosyl trichloroacetimidate (1,
D
3.99 g, 5.39 mmol) in dry CH2Cl2 (100 mL) was stirred.
TMSOTf (30 lL) was added dropwise at )20 ꢁC with
nitrogen protection. The reaction mixture was stirred for
2 h, during which time the temperature gradually raised
to ambient temperature. Then the mixture was neutral-
ized with Et3N. Concentration of the reaction mixture,
followed by purification on a silica gel column with 3:1
petroleum ether–EtOAc as the eluent, gave 3 (4.3 g,
1
87%) as a syrup: ½aꢀ +67.4 (c 1.0, CHCl3); H NMR
D
(400 Hz, CDCl3): d 8.13–7.25 (m, 30H, 6PhH), 6.92 (d,
2H, J 9.1 Hz, CH3OC6H4O–), 6.75 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 5.98 (d, 1H, J3;4 3.2 Hz, H-40), 5.84 (d,
1H, J3;4 3.2 Hz, H-4), 5.76 (m, 1H, J1;2 8.0 Hz, J2;3
10.4 Hz, H-20), 5.70 (dd, 1H, J2;3 10.4 Hz, J1;2 8.0 Hz,

A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
1851
H-2), 5.63–5.58 (m, 1H, CH2@CH–CH2O), 5.54 (dd,
1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-30), 5.17–5.05 (m, 2H,
CH2@CH–CH2O), 5.02 (d, 1H, J1;2 8.0 Hz, H-10), 4.94
(d, 1H, J1;2 8.0 Hz, H-1), 4.43 (dd, 1H, J5;6 6.0 Hz, J6;6
10.4 Hz, H-6), 4.26 (m, 2H, H-6), 4.21 (m, 1H, H-5).
4.12–3.97 (m, 3H, CH2@CH–CH2O, H-5), 3.89 (dd, 1H,
J5;6 6.0 Hz, J6;6 10.4 Hz, H-6), 3.78 (dd, 1H, J3;4 3.2 Hz,
J2;3 10.4 Hz, H-3), 3.67 (s, 3H, CH3O). Anal. Calcd for
C64H56O18: C, 69.05; H, 5.07. Found: C, 69.19; H, 5.06.
5.95–5.89 (m, 3H, H-200, H-400, H-40), 5.74 (d, 1H, J3;4
3.2 Hz, H-4), 5.71 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-
20), 5.61–5.56 (m, 1H, CH2@CH–CH2O), 5.42 (dd, 1H,
J1;2 8.0 Hz, J2;3 10.4 Hz, H-2), 5.14 (d, 1H, J1;2 8.0 Hz, H-
100), 5.13–5.09 (m, 2H, CH2@CH–CH2O), 4.65 (d, 1H,
J1;2 8.0 Hz, H-10), 4.61 (d, 1H, J1;2 8.0 Hz, H-1), 4.02 (dd,
1H, J5;6 5.4 Hz, J6;6 11.2 Hz, H-6), 3.69 (s, 3H, CH3O),
3.69 (dd, 1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-3); 13C NMR
(CDCl3, 100 MHz): d 165.7, 165.6, 165.5, 165.4, 165.3,
165.3, 165.2, 165.2, 165.1 (9C, 9COPh), 101.0, 100.9,
100.8 (3C, C-1). Anal. Calcd for C91H78O26: C, 68.84; H,
4.95. Found: C, 68.69; H, 4.91.
3.4. 2,3,4,6-Tetra-O-benzoyl-b-D-galactopyranosyl-
(1 fi 6)-3-O-allyl-2,4-di-O-benzoyl-a-
trichloroacetimidate (4)
D-galactopyranosyl
3.6. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-
pyranosyl-(1fi 6)-2,4-di-O-benzoyl-b- -galactopyranosyl-
(1 fi 6)-2,3,4-tri-O-benzoyl-b- -galactopyranoside (7)
D-galacto-
To a solution of 3 (3.6 g, 3.24 mmol) in 4:1 CH3CN–H2O
(50 mL) was added ammonium cerium(IV) nitrate,
(CAN), (7.8 g, 14.2 mmol), and the mixture was stirred at
rt for 30 min, at the end of which time TLC (2:1 petroleum
ether–EtOAc) indicated that the reaction was complete.
The mixture was extracted with EtOAc (5 · 50 mL) and
washed with water. The organic layer was concentrated,
and the crude hemiacetal was purified by column chro-
matography (2:1 petroleum ether–EtOAc) to afford a
solid (2.5 g, 2.4 mmol). To a solution of the solid in
CH2Cl2 (80 mL) were added trichloroacetonitrile
(0.48 mL, 4.8 mmol) and anhyd K2CO3 (2.2 g, 16 mmol).
The reaction mixture was stirred overnight at rt and then
filtered, and the filtrate was concentrated in vacuo. The
residue was purified by column chromatography (2:1
petroleum ether–EtOAc) to give 4 (2.54 g, 89%) as a
D
D
To a solution of 6 (2.9 g, 1.87 mmol) in anhyd CH3OH
(50 mL) was added PdCl2 (120 mg), and the mixture was
stirred at rt for 5 h, at the end of which time TLC (1:1
petroleum ether–EtOAc) indicated that the reaction was
complete. The mixture was filtered, and the filtrate was
concentrated. The residue was passed through a silica
gel column with 1.5:1 petroleum ether–EtOAc as the
eluent to give 7 as a syrup (2.57 g, 90%): ½aꢀ +56.3 (c
D
1.0, CHCl3); 1H NMR (400 Hz, CDCl3): d 8.19–7.23 (m,
45H, 9PhH), 6.92 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 6.81
(d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.97–5.92 (m, 2H, H-
200, H-400), 5.90 (d, 1H, J3;4 3.2 Hz, H-40), 5.73 (d, 1H, J3;4
3.2 Hz, H-4), 5.70 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-
20), 5.57 (dd, 1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-300), 5.51
(dd, 1H, J3;4 3.4 Hz, J2;3 10.4 Hz, H-3), 5.46 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-2), 5.15 (d, 1H, J1;2 8.0 Hz, H-100),
4.64 (d, 1H, J1;2 8.0 Hz, H-10), 4.53 (d, 1H, J1;2 8.0 Hz, H-
1), 4.24 (dd, 1H, J5;6 5.4 Hz, J6;6 10.4 Hz, H-6), 3.70 (s,
3H, CH3O), 3.63 (dd, 1H, J3;4 3.4 Hz, J2;3 10.4 Hz, H-30),
3.56 (m, 1H, H-5); 13C NMR (CDCl3, 100 MHz): d 165.6,
165.5, 165.4, 165.3, 165.2, 165.2, 165.1, 165.1, 165.0 (9C,
9COPh), 101.1, 100.7, 100.6 (3C, C-1). Anal. Calcd for
C88H74O26: C, 68.29; H, 4.82. Found: C, 68.20; H, 4.91.
syrup: ½aꢀ +57.1 (c 1.0, CHCl3); 1H NMR (400 Hz,
D
CDCl3): d 8.70 (s, 1H, CNHCCl3), 8.12–7.17 (m, 30H,
6PhH), 6.34 (d, 1H, J1;2 3.2 Hz, a H-1), 5.97 (d, 1H, J3;4
3.2 Hz, H-40), 5.81 (d, 1H, J3;4 3.2 Hz, H-4), 5.80 (dd, 1H,
J1;2 8.0, J2;3 10.4 Hz, H-20), 5.67 (dd, 1H, J1;2 3.2 Hz, J2;3
10.4 Hz, H-2), 5.63–5.56 (m, 1H, CH2@CH–CH2O), 5.52
(dd, 1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-30), 5.17–5.02 (m, 2H,
CH2@CH–CH2O), 4.73 (d, 1H, J1;2 8.0 Hz, b H-1), 4.46
(dd, 1H, J5;6 5.4 Hz, J6;6 11.2 Hz, H-6), 3.98 (dd, 1H, J5;6
5.4 Hz, J6;6 11.2 Hz, H-6), 3.90 (dd, 1H, J3;4 3.4 Hz, J2;3
10.4 Hz, H-3). Anal. Calcd for C59H50Cl3NO17: C, 61.54;
H, 4.38. Found: C, 61.69; H, 4.25.
3.7. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-
pyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -arabinofur-
anosyl-(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyranosyl-
(1 fi 6)-2,3,4-tri-O-benzoyl-b- -galactopyranoside (9)
D-galacto-
L
3.5. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-
D
-galacto-
-galacto-
D-galactopyrano-
D
pyranosyl-(1fi 6)-3-O-allyl-2,4-di-O-benzoyl-b-
D
D
pyranosyl-(1 fi 6)-2,3,4-tri-O-benzoyl-b-
side (6)
Compounds 7 (2.57 g, 1.66 mmol) and 8 (1.21 g,
1.99 mmol) in dry CH2Cl2 (80 mL) were coupled by the
Compounds 4 (2.81 g, 2.44 mmol) and 4-methoxyphen-
yl-2,3,4-tri-O-benzoyl-b- -galactopyranoside (5, 1.32 g,
2.21 mmol) in dry CH2Cl2 (80 mL) were coupled by
same procedure as described in the preparation of 3 to
give tetrasaccharides 9 as a syrup (2.94 g, 89%): ½aꢀ
D
D
1
+41.2 (c 2.0, CHCl3); H NMR (400 MHz, CDCl3): d
the same procedure as described in the preparation of 3
8.09–7.20 (m, 60H, 12PhH), 6.91 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 6.76 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
5.95–5.91 (m, 2H, H-200, H-400), 5.85 (d, 1H, J3;4 3.6 Hz,
H-40), 5.83 (d, 1H, J3;4 3.6 Hz, H-4), 5.68 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-20), 5.64 (dd, 1H, J1;2 8.0 Hz, J2;3
to give trisaccharides 6 as a syrup (2.9 g, 85%): ½aꢀ
D
+39.4 (c 1.0, CHCl3); 1H NMR (400 Hz, CDCl3): d
8.13–7.26 (m, 45H, 9PhH), 6.90 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 6.83 (d, 2H, J 9.1 Hz, CH3OC6H4O–),

1852
A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
10.4 Hz, H-2), 5.58 (dd, 1H, J2;3 10.4 Hz, J3;4 3.6 Hz, H-300),
5.54 (dd, 1H, J2;3 10.4 Hz, J3;4 3.6 Hz, H-3), 5.28 (s, 1H,
Araf-H-1), 5.26 (d, 1H, J2;3 1.2 Hz, Araf-H-2), 5.13 (d,
1H, J1;2 8.0 Hz, H-100), 4.63 (d, 1H, J1;2 8.0 Hz, H-10), 4.62
(d, 1H, J1;2 8.0 Hz, H-1), 4.21 (dd, 1H, J5;6 3.4 Hz, J6;6
10.8 Hz, H-6), 4.01 (dd, 1H, J5;6 5.4 Hz, J6;6 10.8 Hz, H-6),
3.68 (s, 3H, OCH3), 3.55 (m, 1H); 13C NMR (CDCl3,
100 MHz): d 166.1, 166.0, 165.7, 165.8, 165.7, 165.5,
165.4, 165.3, 165.2, 165.2, 165.1, 165.0 (12C, 12COPh),
106.9, 101.5, 101.4, 101.0 (4C, C-1). Anal. Calcd for
5.13 (d, 1H, J1;2 8.0 Hz, H-100), 4.63 (d, 1H, J1;2 8.0 Hz, H-
10), 4.61 (d, 1H, J1;2 8.0 Hz, H-1), 3.65 (s, 3H, OCH3); 13
NMR (CDCl3, 100 MHz): d 166.2, 166.1, 165.7, 165.7,
165.7, 165.6, 165.5, 165.4, 165.3, 165.3, 165.2, 165.2,
165.1, 165.0 (14C, 14COPh), 107.7, 105.9 (2Araf-C-1),
101.4, 101.0, 100.9 (3Galp-C-1). Anal. Calcd for
C
C
133H110O39: C, 68.49; H, 4.75. Found: C, 68.26; H, 4.87.
3.10. 2,3,4,6-Tetra-O-benzoyl-b-
(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -arabinofuranosyl-
(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofuranosyl-(1 fi 3)]-
2,4-di-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-2,3,4-tri-
O-benzoyl-a- -galactopyranosyl trichloroacetimidate (13)
D-galactopyranosyl-
L
C
114H94O33: C, 68.73; H, 4.76. Found: C, 68.87; H, 4.80.
L
D
3.8. 2,3,4,6-Tetra-O-benzoyl-b-
[2,3,5-tri-O-benzoyl-a- -arabinofuranosyl-(1 fi 3)]-2,4-
di-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-2,3,4-tri-O-
benzoyl-a- -galactopyranosyl trichloroacetimidate (10)
D
-galactopyranosyl-(1 fi 6)-
D
L
D
To a solution of 12 (2.68 g, 1.15 mmol) in 4:1 CH3CN–
H2O (50 mL) was added CAN (3.0 g, 5.75 mmol), and the
mixture was treated by the same procedure as described
in the preparation of 4 to give 13 as a syrup (1.60 g, 59%):
D
To a solution of 9 (2.94 g, 1.48 mmol) in 4:1 CH3CN–
H2O (50 mL) was added CAN (3.9 g, 7.5 mmol), and the
mixture was treated by the same procedure as described
in the preparation of 4 to give 10 as a syrup (1.87 g, 63%):
½aꢀ +43.2 (c 2.0, CHCl3); 1H NMR (400 MHz, CDCl3):
D
d 8.21 (s, 1H, NH), 8.03–7.16 (m, 70H, 14PhH), 6.73 (d,
1H, J1;2 3.6 Hz, H-1), 6.05 (d, 1H, J3;4 3.6 Hz, H-400), 6.02
(dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-200), 5.98 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-20), 5.87 (d, 1H, J3;4 3.6 Hz, H-40),
5.81 (d, 1H, J3;4 3.6 Hz, H-4), 5.64 (d, 1H, J2;3 1.2 Hz,
Araf-H-2), 5.60 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2),
5.57 (dd, 1H, J2;3 10.4 Hz, J3;4 3.2 Hz, H-300), 5.52 (dd, 1H,
1
½aꢀ +57.4 (c 1.0, CHCl3); H NMR (400 Hz, CDCl3): d
D
8.09 (s, 1H, NH), 8.02–7.21 (m, 60H, 12PhH), 6.73 (d,
1H, J1;2 3.6 Hz, H-100), 6.04 (d, 1H, J3;4 3.6 Hz, H-400),
5.85–5.77 (m, 3H, H-200, H-40, H-4), 5.65 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-20), 5.59 (dd, 1H, J1;2 8.0 Hz, J2;3
10.4 Hz, H-2), 5.52 (dd, 1H, J2;3 10.4 Hz, J3;4 3.6 Hz, H-
300), 5.48 (dd, 1H, J2;3 10.4 Hz, J3;4 3.6 Hz, H-3), 5.26 (s,
1H, Araf-H-1), 5.23 (d, 1H, J2;3 2.4 Hz, Araf-H-2), 4.59
(d, 1H, J1;2 8.0 Hz, H-10); 13C NMR (CDCl3, 100 MHz): d
166.1, 166.0, 165.7, 165.8, 165.7, 165.5, 165.4, 165.3,
165.2, 165.2, 165.1, 165.0 (12C, 12COPh), 106.9 (Araf-C-1),
101.5, 101.4, 101.0 (3Galp-C-1). Anal. Calcd for
J
2;3 10.4 Hz, J3;4 3.6 Hz, H-3), 5.46 (s, 1H, Araf-H-1), 5.27
(d, 1H, J2;3 2.4 Hz, Araf-H-2), 5.26 (s, 1H, Araf-H-1),
5.14 (d, 1H, J1;2 8.0 Hz, H-100), 4.61 (d, 1H, J1;2 8.0 Hz, H-
10), 4.59 (d, 1H, J1;2 8.0 Hz, H-1); 13C NMR (CDCl3,
100 MHz): d 166.2, 166.1, 165.8, 165.7, 165.7, 165.6,
165.5, 165.4, 165.4, 165.3, 165.2, 165.2, 165.1, 165.0
(14C, 14COPh), 107.8, 105.8 (2Araf-C-1), 101.3, 101.0,
100.9 (3Galp-C-1). Anal. Calcd for C128H104Cl3NO38: C,
64.85; H, 4.42. Found: C, 64.61; H, 4.32.
C109H88Cl3NO32: C, 64.48; H, 4.37. Found: C, 64.22; H, 4.28.
3.9. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-
pyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -arabinofuranosyl-
(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofuranosyl-(1 fi 3)]-
2,4-di-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-2,3,4-tri-
-galactopyranoside (12)
D-galacto-
L
3.11. 4-Methoxyphenyl 6-O-acetyl-2,3,4-tri-O-benzoyl-b-
L
D
-galactopyranosyl-(1 fi 6)-3-O-allyl-2,4-di-O-benzoyl-b-
-galactopyranoside (15)
D
D
O-benzoyl-b-
D
A solution of 2 (3.0 g, 5.61 mmol) and 6-O-acetyl-2,3,4-
tri-O-benzoyl-a- -galactopyranosyl trichloroacetimid-
Compounds
7
(2.0 g, 1.29 mmol) and 11 (1.47 g,
1.55 mmol) in dry CH2Cl2 (60 mL) were coupled by the
D
ate (14, 4.2 g, 6.18 mmol) in dry CH2Cl2 (100 mL) was
stirred. TMSOTf (50 lL) was added dropwise at )20 ꢁC
with nitrogen protection. The reaction mixture was
stirred for 2 h, during which time the temperature
gradually raised to ambient temperature. Then the
mixture was neutralized with Et3N. Concentration of
the reaction mixture, followed by purification on a silica
gel column with 3:1 petroleum ether–EtOAc as the
same procedure as described in the preparation of 3 to
give pentasaccharide 12 as a syrup (2.68 g, 89%): ½aꢀ
D
1
+38.2 (c 2.0, CHCl3); H NMR (400 MHz, CDCl3): d
8.09–7.18 (m, 70H, 14PhH), 6.90 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 6.73 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
5.95 (d, 1H, J3;4 3.6 Hz, H-400), 5.94 (dd, 1H, J1;2 8.0 Hz,
J
2;3 10.4 Hz, H-200), 5.88 (d, 1H, J3;4 3.6 Hz, H-40), 5.79 (d,
1H, J3;4 3.6 Hz, H-4), 5.68 (dd, 1H, J1;2 8.0 Hz, J2;3
10.4 Hz, H-20), 5.66–5.60 (m, 2H), 5.63 (d, 1H, J2;3 1.2 Hz,
Araf-H-2), 5.60 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2),
5.56 (dd, 1H, J2;3 10.4 Hz, J3;4 3.2 Hz, H-300), 5.52 (dd, 1H,
eluent, gave 15 as a syrup (4.78 g, 81%): ½aꢀ +68.4 (c
D
1.0, CHCl3); 1H NMR (400 Hz, CDCl3): d 8.13–7.24 (m,
25H, 5PhH), 6.91 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 6.73
(d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.83 (d, 1H, J3;4
3.2 Hz, H-40), 5.80 (d, 1H, J3;4 3.2 Hz, H-4), 5.76 (m, 1H,
J1;2 8.0 Hz, J2;3 10.4 Hz, H-20), 5.68 (dd, 1H, J1;2 8.0 Hz,
J
2;3 10.4 Hz, J3;4 3.6 Hz, H-3), 5.48 (s, 1H, Araf-H-1), 5.27
(d, 1H, J2;3 2.4 Hz, Araf-H-2), 5.25 (s, 1H, Araf-H-1),

A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
1853
J2;3 10.4 Hz, H-2), 5.70–5.65 (m, 1H, CH2@CH–CH2O),
5.50 (dd, 1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-30), 5.18–5.03
(m, 2H, CH2@CH–CH2O), 5.01 (d, 1H, J1;2 8.0 Hz, H-
10), 4.90 (d, 1H, J1;2 8.0 Hz, H-1), 3.81 (dd, 1H, J5;6
6.0 Hz, J6;6 10.4 Hz, H-6), 3.67 (s, 3H, CH3O), 1.94 (s,
3H, CH3CO). Anal. Calcd for C59H54O18: C, 67.42; H,
5.18. Found: C, 67.49; H, 5.22.
1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-300), 5.47 (dd, 1H, J3;4
3.2 Hz, J2;3 10.4 Hz, H-3), 5.39 (dd, 1H, J1;2 8.0 Hz, J2;3
10.4 Hz, H-2), 5.15 (d, 1H, J1;2 8.0 Hz, H-100), 5.13–4.98
(m, 2H, CH2@CH–CH2O), 4.61 (d, 1H, J1;2 8.0 Hz, H-
10), 4.58 (d, 1H, J1;2 8.0 Hz, H-1), 4.24 (dd, 1H, J5;6
5.4 Hz, J6;6 11.2 Hz, H-6), 4.12–4.02 (2H, CH2@CH–
CH2O), 3.70 (s, 3H, CH3O), 3.65 (dd, 1H, J3;4 3.2 Hz,
J2;3 10.4 Hz, H-30), 1.99 (s, 3H, CH3CO); 13C NMR
(100 MHz, CDCl3): d 165.5, 165.4, 165.3, 165.2, 165.2,
165.1, 165.1, 165.0 (8C, 8COPh), 101.2, 100.7, 100.6
(3C, C-1). Anal. Calcd for C86H76O26: C, 67.71; H, 5.02.
Found: C, 67.99; H, 4.93.
3.12. 6-O-Acetyl-2,3,4-tri-O-benzoyl-b-
D
-galactopyrano-
D-galactopyr-
syl-(1 fi 6)-3-O-allyl-2,4-di-O-benzoyl-a-
anosyl trichloroacetimidate (16)
To a solution of 15 (4.78 g, 4.55mmol) in 4:1 CH3CN–
H2O (50 mL) was added CAN (12.1 g, 22.8 mmol), and
the mixture was stirred at rt for 30min, at the end of which
time TLC (2:1 petroleum ether–EtOAc) indicated that the
reaction was complete. The mixture was extracted with
EtOAc (5· 50mL) and washed with water. The organic
layer was concentrated under reduced pressure, and the
crude hemiacetal was purified by column chromatography
(2:1 petroleum ether–EtOAc) to afford a solid (3.2 g,
3.38mmol). To a solution of the solid in CH2Cl2 (80 mL)
were added trichloroacetonitrile (0.58 mL, 0.52mmol)
and anhyd K2CO3 (2.0 g, 13.5mmol). The reaction mix-
ture was stirred overnight at rt and then filtered, and the
filtrate was concentrated in vacuo. The residue was puri-
fied by column chromatography (2:1 petroleum ether–
3.14. 4-Methoxyphenyl 6-O-acetyl-2,3,4-tri-O-benzoyl-b-
D
-galactopyranosyl-(1fi 6)-2,4-di-O-benzoyl-b-
D
-galacto-
D-galactopyrano-
pyranosyl-(1 fi 6)-2,3,4-tri-O-benzoyl-b-
side (18)
To a solution of 17 (3.14 g, 2.06 mmol) in anhyd CH3OH
(50 mL) was added PdCl2 (100 mg), and the mixture was
stirred at rt for 5 h. Purification of the product by col-
umn chromatography with 1.5:1 petroleum ether–
EtOAc as the eluent gave 18 (2.59 g, 85%) as a syrup:
1
½aꢀ +69.3 (c 1.0, CHCl3); H NMR (400 Hz, CDCl3): d
D
8.09–7.23 (m, 40H, 8PhH), 6.96 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 6.83 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
5.97–5.92 (m, 2H, H-200, H-400), 5.78 (d, 1H, J3;4 3.2 Hz,
H-40), 5.67 (d, 1H, J3;4 3.2 Hz, H-4), 5.65 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-20), 5.57 (dd, 1H, J3;4 3.2 Hz, J2;3
10.4 Hz, H-300), 5.47 (dd, 1H, J3;4 3.2 Hz, J2;3 10.4 Hz, H-
3), 5.26 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2), 5.15 (d,
1H, J1;2 8.0 Hz, H-100), 4.64 (d, 1H, J1;2 8.0 Hz, H-10), 4.53
(d, 1H, J1;2 8.0 Hz, H-1), 4.24 (dd, 1H, J5;6 5.4 Hz, J6;6
11.2 Hz, H-6), 3.70 (s, 3H, CH3O), 1.99 (s, 3H, CH3CO);
13C NMR (100 MHz, CDCl3): d 165.5, 165.4, 165.3,
165.2, 165.2, 165.1, 165.1, 165.0 (8C, 8COPh), 101.2,
100.7, 100.6 (3C, C-1). Anal. Calcd for C83H72O26: C,
67.11; H, 4.88. Found: C, 67.27; H, 4.80.
EtOAc) to give 16 as a syrup (3.2 g, 89%): ½aꢀ +49.2 (c
D
1
1.0, CHCl3); H NMR (400Hz, CDCl3): d 8.24 (s, 1H,
NH), 8.12–7.22 (m, 25H, 5PhH), 6.64 (d, 1H, J1;2 3.6 Hz, a
H-1), 5.90 (d, 1H, J3;4 3.2 Hz, H-40), 5.81 (d, 1H, J3;4
3.2 Hz, H-4), 5.80–5.69 (m, 1H, CH2@CH–CH2O), 5.70
(dd, 1H, J1;2 8.0 Hz, J2;3 10.4Hz, H-20), 5.67 (dd, 1H, J1;2
3.2 Hz, J2;3 10.4 Hz, H-2), 5.57 (dd, 1H, J3;4 3.2 Hz, J2;3
10.4 Hz, H-30), 5.23–5.06 (m, 2H, CH2@CH–CH2O), 4.80
(d, 1H, J1;2 8.0 Hz, H-10), 4.46 (dd, 1H, J5;6 5.4 Hz, J6;6
11.2 Hz, H-6), 3.79 (dd, 1H, J5;6 5.4 Hz, J6;6 11.2Hz, H-6),
1.94 (s, 3H, CH3CO). Anal. Calcd for C54H48Cl3NO17: C,
59.54; H, 4.44. Found: C, 59.71; H, 4.32.
3.15. 4-Methoxyphenyl 6-O-acetyl-2,3,4-tri-O-benzoyl-b-
3.13. 4-Methoxyphenyl 6-O-acetyl-2,3,4-tri-O-benzoyl-b-
D
-galactopyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a-
binofuranosyl-(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyrano-
syl-(1 fi 6)-2,3,4-tri-O-benzoyl-b- -galactopyranoside (19)
L-ara-
D
-galactopyranosyl-(1 fi 6)-3-O-allyl-2,4-di-O-benzoyl-b-
-galactopyranosyl-(1 fi 6)-2,3,4-tri-O-benzoyl-b-
galactopyranoside (17)
D
D
D
-
D
Coupling of 18 (2.87 g, 1.93 mmol) with 8 (1.52 g,
2.5 mmol) under the same conditions as described for
the coupling of 1 with 2 gave tetrasaccharide 19 (3.3 g,
Compounds 16 (3.0 g, 2.7 mmol) and 4-methoxyphenyl
2,3,4-tri-O-benzoyl-b- -galactopyranoside (5, 1.37 g,
2.25 mmol) in dry CH2Cl2 (50 mL) were coupled by the
D
1
89%) as a syrup: ½aꢀ +41.2 (c 1.0, CHCl3); H NMR
D
same procedure as described in the preparation of 3 to
give trisaccharide 17 (3.14 g, 85%) as a syrup: ½aꢀ +22.3
(400 MHz, CDCl3): d 8.03–7.20 (m, 55H, 11PhH), 6.96
(d, 2H, J 9.1 Hz, CH3OC6H4O–), 6.86 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 5.95–5.90 (m, 2H, H-200, H-400), 5.83 (d,
1H, J3;4 3.4 Hz, H-40), 5.73 (d, 1H, J3;4 3.4 Hz, H-4),
5.66–5.60 (m, 2H, H-20, H-2), 5.58 (dd, 1H, J3;4 3.4 Hz,
J2;3 10.4 Hz, H-300), 5.49 (dd, 1H, J3;4 3.4 Hz, J2;3 10.4 Hz,
H-3), 5.28 (s, 1H, Araf-H-1), 5.26 (d, 1H, J2;3 1.2 Hz,
Araf-H-2), 5.13 (d, 1H, J1;2 8.0 Hz, H-100), 4.68 (d, 1H,
D
1
(c 1.0, CHCl3); H NMR (400 Hz, CDCl3): d 8.09–7.23
(m, 40H, 8PhH), 6.96 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
6.83 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.95–5.90 (m, 2H,
H-200, H-400), 5.78 (d, 1H, J3;4 3.2 Hz, H-40), 5.73 (d, 1H,
J3;4 3.2 Hz, H-4), 5.66 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz,
H-20), 5.61–5.58 (m, 1H, CH2@CH–CH2O), 5.56 (dd,

1854
A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
J1;2 8.0 Hz, H-10), 4.58 (d, 1H, J1;2 8.0 Hz, H-1), 4.21 (dd,
1H, J5;6 3.4 Hz, J6;6 10.8 Hz, H-6), 4.13 (dd, 1H, J3;4
3.2 Hz, J2;3 10.4 Hz, H-30), 4.03 (dd, 1H, J5;6 6.0 Hz, J6;6
10.8 Hz, H-6), 3.68 (s, 3H, OCH3), 3.47 (m, 1H, H-5),
1.99 (s, 3H, CH3CO); 13C NMR (100 MHz, CDCl3): d
166.1, 166.0, 165.8, 165.7, 165.5, 165.4, 165.3, 165.2,
165.2, 165.1, 165.0 (11C, 11COPh), 107.2 (Araf-C-1),
101.5, 101.4, 101.0 (3Galp-C-1). Anal. Calcd for
J3;4 3.6 Hz, H-400), 5.78 (d, 1H, J3;4 3.6 Hz, H-40), 5.74 (d,
1H, J3;4 3.6 Hz, H-4), 5.65 (dd, 1H, J1;2 8.0 Hz, J2;3
10.4 Hz, H-20), 5.61 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2),
5.56 (dd, 1H, J2;3 10.4 Hz, J3;4 3.2 Hz, H-300), 5.49 (s, 1H,
Araf-H-1), 5.43 (dd, 1H, J2;3 10.4 Hz, J3;4 3.6 Hz, H-3), 5.28
(d, 1H, J2;3 2.4 Hz, Araf-H-2), 5.27 (s, 1H, Araf-H-1), 5.13
(d, 1H, J1;2 8.0 Hz, H-100), 4.61 (d, 1H, J1;2 8.0 Hz, H-10),
4.55 (d, 1H, J1;2 8.0Hz, H-1), 3.67 (s, 3H, OCH3), 1.92
(CH3CO); 13C NMR (CDCl3, 100MHz): d 166.2, 166.1,
165.7, 165.7, 165.6, 165.5, 165.4, 165.3, 165.3, 165.2, 165.2,
165.1, 165.0 (13C, 13COPh), 107.6, 105.9 (2Araf-C-1),
101.4, 100.9, 100.6 (3Galp-C-1). Anal. Calcd for
C
109H92O33: C, 67.83; H, 4.81. Found: C, 68.01; H, 4.89.
3.16. 4-Methoxyphenyl 2,3,4-tri-O-benzoyl-b-
pyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -arabinofur-
anosyl-(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyranosyl-
(1 fi 6)-2,3,4-tri-O-benzoyl-b- -galactopyranoside (20)
D-galacto-
L
D
C128H108O39: C, 67.72; H, 4.79. Found: C, 67.87; H, 4.65.
D
3.18. 4-Methoxyphenyl 2,3,4-tri-O-benzoyl-b-
pyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -arabinofur-
anosyl-(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofuranosyl-
(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-
2,3,4-tri-O-benzoyl-b- -galactopyranoside (22)
D-galacto-
To a solution of 19 (2 g, 1.03 mmol) in 1:1 CH3OH–
CH2Cl2 (100 mL) was added CH3COCl (1 mL), and the
reaction was carried out at rt for 24 h. Tetrasaccharide 20
(1.7 g, 87%) was obtained as a syrup after purifying the
product by column chromatography with 1.5:1 petro-
L
L
D
D
leum ether–EtOAc as the eluent: ½aꢀ +31.6 (c 1.0,
To a solution of 21 (1.9 g, 0.84 mmol) in 1:1 CH3OH–
CH2Cl2 (100 mL) was added CH3COCl (1 mL), and the
reaction was carried out at rt for 24 h. After purifying the
product by column chromatography with 1.5:1 petro-
leum ether–EtOAc as the eluent, 22 was obtained as a
D
1
CHCl3); H NMR (400 MHz, CDCl3): d 8.03–7.19 (m,
55H, 11PhH), 6.96 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 6.86
(d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.95–5.90 (m, 2H, H-
200, H-400), 5.89 (d, 1H, J3;4 3.6 Hz, H-40), 5.71 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-20), 5.68 (d, 1H, J3;4 3.6 Hz, H-4),
5.62 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2), 5.58 (dd, 1H,
J2;3 10.4 Hz, J3;4 3.6 Hz, H-300), 5.46 (dd, 1H, J2;3 10.4 Hz,
J3;4 3.6 Hz, H-3), 5.28 (s, 1H, Araf-H-1), 5.23 (d, 1H, J2;3
1.2 Hz, Araf-H-2), 5.13 (d, 1H, J1;2 8.0 Hz, H-100), 5.04
(dd, 1H, J5;6 6.0 Hz, J6;6 12 Hz, H-6), 4.75 (dd, 1H, J5;6
3.4 Hz, J6;6 12 Hz, H-6), 4.64 (d, 1H, J1;2 8.0 Hz, H-10),
4.57 (d, 1H, J1;2 8.0 Hz, H-1), 4.21 (dd, 1H, J5;6 3.4 Hz,
J6;6 10.8 Hz, H-6), 4.13 (dd, 1H, J2;3 10.4 Hz, J3;4 3.2 Hz,
H-30), 3.64 (s, 3H, OCH3), 3.51 (m, 1H, H-5), 3.36 (dd,
1H, J5;6 6.0 Hz, J6;6 10.8 Hz, H-6), 3.24 (dd, 1H, J5;6
5.6 Hz, J6;6 10.8 Hz, H-6); 13C NMR (CDCl3, 100 MHz):
d 166.1, 166.0, 165.8, 165.7, 165.5, 165.4, 165.3, 165.2,
165.2, 165.1, 165.0 (11C, 11COPh), 107.2 (Araf-C-1),
101.5, 101.4, 101.0 (3Galp-C-1). Anal. Calcd for
1
syrup (1.5 g, 81%): ½aꢀ +61.4 (c 1.0, CHCl3); H NMR
D
(400 Hz, CDCl3): d 8.08–7.15 (m, 65H, 13PhH), 6.91 (d,
2H, J 9.1 Hz, CH3OC6H4O–), 6.73 (d, 2H, J 9.1 Hz,
CH3OC6H4O–), 5.95 (dd, 1 H, J1;2 8.0 Hz, J2;3 10.4 Hz,
H-200), 5.93 (d, 1H, J3;4 3.6 Hz, H-400), 5.84 (d, 1H, J3;4
3.6 Hz, H-40), 5.50 (s, 1H, Araf-H-1), 5.46 (dd, 1H, J2;3
10.4 Hz, J3;4 3.6 Hz, H-3), 5.28 (d, 1H, J2;3 2.4 Hz, Araf-
H-2), 5.27 (s, 1H, Araf-H-1), 5.14 (d, 1H, J1;2 8.0 Hz, H-
100), 4.68 (dd, 1H, J5;6 4.4 Hz, J6;6 10.4 Hz, H-6), 4.61 (d,
1H, J1;2 8.0 Hz, H-10), 4.55 (d, 1H, J1;2 8.0 Hz, H-1), 3.67
(s, 3H, OCH3), 3.49 (dd, 1H), 3.37 (dd, 1H, J5;6 6.8 Hz,
J
6;6 12 Hz, H-6), 3.28 (dd, 1H, J5;6 6.8 Hz, J6;6 12 Hz, H-6);
13C NMR (CDCl3, 100 MHz): d 166.2, 166.1, 165.7,
165.7, 165.6, 165.5, 165.4, 165.3, 165.3, 165.2, 165.2,
165.1, 165.0 (13C, 13COPh), 107.6, 105.9 (2Araf-C-1),
101.4, 100.9, 100.6 (3Galp-C-1). Anal. Calcd for
C
107H90O32: C, 68.07; H, 4.81. Found: C, 68.37; H, 4.69.
C
126H106O38: C, 67.91; H, 4.79. Found: C, 67.73; H, 4.72.
3.17. 4-Methoxyphenyl 6-O-acetyl-2,3,4-tri-O-benzoyl-b-
-galactopyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -ara-
binofuranosyl-(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofur-
anosyl-(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyranosyl-
(1 fi 6)-2,3,4-tri-O-benzoyl-b- -galactopyranoside (21)
D
L
3.19. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-
pyranosyl-(1 fi 6)-[2,3,5-tri-O-benzoyl-a- -arabinofur-
anosyl-(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyranosyl-
(1 fi 6)-2,3,4-tri-O-benzoyl-b- -galactopyranosyl-(1fi 6)-
2,3,4-tri-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-[2,3,5-
tri-O-benzoyl-a- -arabinofuranosyl-(1 fi 5)-2,3-di-O-ben-
zoyl-a-
D-galacto-
L
L
D
D
D
D
D
Compounds 18 (1.50 g, 1.01 mmol) and 11 (1.14 g,
1.21 mmol) in dry CH2Cl2 (50 mL) were coupled by the
same procedure as described in the preparation of 3 to
L
L
-arabinofuranosyl-(1 fi 3)]-2,4-di-O-benzoyl-b-
D-
galactopyranosyl-(1 fi 6)-2,3,4-tri-O-benzoyl-b-
topyranoside (23)
D-galac-
give pentasaccharides 21 as a syrup (1.90 g, 83%): ½aꢀ
D
+67.2 (c 1.0, CHCl3); 1H NMR (400 Hz, CDCl3): d 8.03–
7.18 (m, 65H, 13PhH), 6.93 (d, 2H,
CH3OC6H4O–), 6.73 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
5.95 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-200), 5.93 (d, 1H,
J
9.1 Hz,
Compounds 10 (436 mg, 0.22 mmol) and 22 (400 mg,
0.18 mmol) in dry CH2Cl2 (50 mL) were coupled by the
same procedure as described in the preparation of 3 to

A. Li, F. Kong / Carbohydrate Research 339 (2004) 1847–1856
1855
give 23 as a syrup (595 mg, 81%): ½aꢀ +73.6 (c 1.0,
give 25 as a syrup (712 mg, 81%): ½aꢀ +71.3 (c 1.0,
D
D
CHCl3); 1H NMR (400 Hz, CDCl3): d 8.03–7.16 (m,
125H, 25PhH), 6.88 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
6.73 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.90 (dd, 1H, J1;2
8.0 Hz, J2;3 10.4 Hz, H-2), 5.89 (d, 1H, J3;4 3.2 Hz, H-4),
5.88 (d, 1H, J3;4 3.2 Hz, H-4), 5.72 (d, 1H, J3;4 3.2 Hz, H-
4), 5.38 (dd, 1H, J2;3 10.4 Hz, J3;4 3.2 Hz, H-3), 5.09 (d,
1H, J1;2 8.0 Hz, H-1), 4.56 (d, 1H, J1;2 8.0 Hz, H-1), 4.43
(d, 1H, J1;2 8.0 Hz, H-1), 4.41 (d, 1H, J1;2 8.0 Hz, H-1),
4.29 (d, 1H, J1;2 7.6 Hz, H-1), 4.23 (d, 1H, J1;2 8.0 Hz, H-
1), 3.69 (s, 3H, CH3O); 13C NMR (CDCl3, 100 MHz): d
167.3, 167.1, 167.0, 166.3, 166.3, 166.2, 166.1, 166.0,
165.8, 165.7, 165.6, 165.6, 165.5, 165.4, 165.4, 165.3,
165.3, 165.2, 165.2, 165.1, 165.0, 164.9, 164.7, 164.7,
164.5 (25C, 25COPh), 107.9, 107.7, 105.7 (3Araf-C-1),
101.5, 101.4, 101.1, 101.0, 100.9, 100.5 (6Galp-C-1).
Anal. Calcd for C233H192O69: C, 68.32; H, 4.72. Found:
C, 68.49; H, 4.61.
CHCl3); 1H NMR (400 Hz, CDCl3): d 8.11–7.17 (m,
125H, 25PhH), 6.92 (d, 2H, J 9.1 Hz, CH3OC6H4O–),
6.83 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.91 (d, 1H, J3;4
3.2 Hz, H-4), 5.90 (dd, 1H, J1;2 8.0 Hz, J2;3 10.4 Hz, H-2),
5.89 (d, 1H, J3;4 3.2 Hz, H-4), 5.27 (d, 1H, J2;3 2.4 Hz,
Araf-H-2), 5.26 (s, 1H, Araf-H-1), 5.10 (d, 1H, J1;2
8.0 Hz, H-1), 4.59 (d, 1H, J1;2 8.0 Hz, H-1), 3.69 (s, 3H,
CH3O); 13C NMR (CDCl3, 100 MHz): d 167.2, 167.1,
167.0, 166.4, 166.3, 166.2, 166.1, 166.0, 165.8, 165.7,
165.7, 165.6, 165.5, 165.4, 165.4, 165.3, 165.3, 165.2,
165.2, 165.1, 165.0, 164.8, 164.7, 164.7, 164.5 (25C,
25COPh), 107.8, 107.7, 105.8 (3Araf-C-1), 101.5, 101.4,
101.3, 101.0, 100.9, 100.5 (6Galp-C-1). Anal. Calcd
for C233H192O69: C, 68.32; H, 4.72. Found: C, 68.61; H,
4.89.
3.22. 4-Methoxyphenyl b-
L
D
-galactopyranosyl-(1fi 6)-[a-
-arabinofuranosyl-(1fi 5)-a- -arabinofuranosyl-(1fi 3)]-
-galactopyranosyl-(1fi 6)-b- -galactopyranosyl-
-galactopyranosyl-(1 fi 6)-[a- -arabinofur-
-galactopyranosyl-(1 fi 6)-b- -galac-
L
3.20. 4-Methoxyphenyl b-
arabinofuranosyl-(1 fi 3)]-b-
D
-galactopyranosyl-(1 fi 6)-[a-
-galactopyranosyl-(1 fi 6)-b-
-galactopyranosyl-
L
-
b-D
D
D
(1 fi 6)-b-
D
L
D
-galactopyranosyl-(1 fi 6)-b-
D
anosyl-(1 fi 3)]-b-
D
D
(1 fi 6)-[a-
anosyl-(1 fi 3)]-b-
topyranoside (24)
L
-arabinofuranosyl-(1 fi 5)-a-
L
-arabinofur-
topyranoside (26)
D
-galactopyranosyl-(1 fi 6)-b-
D-galac-
Compound 25 (712 mg, 0.17 mmol) was dissolved in a
satd solution of NH3 in MeOH (80 mL). After a week at
rt, the reaction mixture was concentrated, and the resi-
due was purified by chromatography on Sephadex LH-
20 (MeOH) to afford 26 as an amorphous solid (218 mg,
Compound 23 (595 mg, 0.14 mmol) was dissolved in a
satd solution of NH3 in MeOH (80 mL). After a week at
rt, the reaction mixture was concentrated, and the resi-
due was purified by chromatography on Sephadex LH-
20 (MeOH) to afford 24 as an amorphous solid(175 mg,
84%): ½aꢀ +49.1 (c 1.0, H2O); 1H NMR (D2O,
D
400 MHz): d 7.07 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 6.98
(d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.21 (s, 1H, Araf-H-1),
5.11 (s, 1H, Araf-H-1), 5.01 (s, 1H, Araf-H-1), 4.95 (d,
1H, J1;2 8.0 Hz, Galp-H-1), 4.85 (d, 1H, J1;2 7.6 Hz, Galp-
H-1), 4.66 (d, 1H, J1;2 8.0 Hz, Galp-H-1), 4.38 (d, 1H, J1;2
7.2 Hz, Galp-H-1), 4.32 (m, 2H, 2Galp-H-1); 13C NMR
(100 MHz, D2O): d 109.3, 109.3, 107.2 (3 Araf-C-1),
103.4, 103.3, 103.3, 103.1, 102.8, 101.6 (6Galp-C-1).
MALDITOF-MS calcd for C58H92O44: 1493.32 [M].
Found: 1493.2 [M].
81%): ½aꢀ +56.7 (c 1.0, H2O); 1H NMR (D2O,
D
400 MHz): d 7.08 (d, 2H, J 9.1 Hz, CH3OC6H4O–), 6.89
(d, 2H, J 9.1 Hz, CH3OC6H4O–), 5.29 (s, 1H, Araf-H-1),
5.13 (s, 1H, Araf-H-1), 5.11 (s, 1H, Araf-H-1), 4.97 (d,
1H, J1;2 8.0 Hz, Galp-H-1), 4.86 (d, 1H, J1;2 7.6 Hz, Galp-
H-1), 4.70 (d, 1H, J1;2 8.0 Hz, Galp-H-1), 4.40 (d, 1H, J1;2
7.2 Hz, Galp-H-1), 4.38 (m, 2H, 2Galp-H-1); 13C NMR
(100 MHz, D2O): d 109.4, 109.3, 107.4 (3Araf-C-1),
103.4, 103.4, 100.3, 103.2, 102.9, 101.7 (6Galp-C-1).
MALDITOF-MS calcd for C58H92O44: 1493.32 [M].
Found: 1493.2 [M].
Acknowledgements
3.21. 4-Methoxyphenyl 2,3,4,6-tetra-O-benzoyl-b-
galactopyranosyl-(1fi 6)-[2,3,5-tri-O-benzoyl-a- -arabino-
furanosyl-(1 fi 5)-2,3-di-O-benzoyl-a- -arabinofuranosyl-
(1 fi 3)]-2,4-di-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-
2,3,4-tri-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-2,3,4-
tri-O-benzoyl-b- -galactopyranosyl-(1 fi 6)-[2,3,5-tri-O-
benzoyl-a- -arabinofuranosyl-(1 fi 3)]-2,4-di-O-benzoyl-
b- -galactopyranosyl-(1 fi 6)-2,3,4-tri-O-benzoyl-b-
galactopyranoside (25)
D-
L
This work was supported by The National Natural
Science Foundation of China (Projects 30070185 and
39970864).
L
D
D
D
L
References
D
D-
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1856
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