Synthesis of a natural oligosaccharide antibiotic active against Helicobacter pylori

Article abstract of DOI:10.1021/jo070669p

(Chemical Equation Presented) An oligosaccharide active against Helicobacter pylori was synthesized in a highly efficient manner for the first time. The anti-H. pylori oligosaccharide structure is a core-2 branched-type oligosaccharide with a characterist

Full text of DOI:10.1021/jo070669p

Synthesis of a Natural Oligosaccharide Antibiotic Active against
Helicobacter pylori
Shino Manabe,* Kazuyuki Ishii, and Yukishige Ito*
RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
smanabe@riken.jp
ReceiVed April 2, 2007
An oligosaccharide active against Helicobacter pylori was synthesized in a highly efficient manner for
the first time. The anti-H. pylori oligosaccharide structure is a core-2 branched-type oligosaccharide
with a characteristic R-N-acetylglucosamine at the nonreducing end. The oligosaccharide was synthesized
from the nonreducing end to the reducing end, with an N-benzyl-2,3-oxazolidinone-carrying glycosyl
donor used to introduce an R-N-acetylglucosamine at the nonreducing end. Complete chemoselective
activation of a bromo sugar in the presence of a thioglycoside acceptor was achieved, and the use of
2,6-dimethylphenyl thioglycoside prevented the aglycon transfer observed when the corresponding phenyl
thioglycoside is used as an acceptor.
Introduction
Research on Cancer (IARC) classified Helicobacter pylori as a
class I carcinogenic agent.
Helicobacter pylori, a Gram-negative bacterium, infects the
stomachs of nearly half the human population.1 Phylogeographic
studies indicate that H. pylori originated in Africa and that H.
pylori accompanied anatomically modern humans during their
migrations from Africa.2 Thus, H. pylori has infected humans
for the past 50 000 years. Since the potential pathogenic
character of H. pylori was first demonstrated,3 accumulated
evidence strongly suggests that H. pylori causes gastric ulcers,
carcinoma, and cancer.4 In 1994, the International Agency for
Gastric mucins are classified into two types based on their
histochemical properties.5 The first is a surface mucous cell-
type mucin, secreted from surface mucous cells, while the
second is found in deeper portions of the mucosa and is secreted
by gland mucous cells including mucous neck cells, cardiac
gland cells, and pyloric gland cells. H. pylori bacteria colonize
surface mucous cell-type mucin6 where two carbohydrate
structures, Lewis b and sialyl dimeric Lewis X, act as specific
ligands for H. pylori infection. H. pylori bacteria are rarely found
deep in the mucous. In 2004, Nakayama’s group found an
O-linked glycoprotein, secreted from deeper mucins, that inhibits
H. pylori growth.7 This anti-H. pylori glycoprotein (1a) has a
core-2 branched-type oligosaccharide with a characteristic R-N-
acetylglucosamine at the nonreducing end.8 Growth inhibition
(1) Falush, D.; Wirth, T.; Linz, B.; Pritchard, J. K.; Stephens, M.; Kidd,
M.; Blaser, M. J.; Graham, D. Y.; Vacher, S.; Perez-Perez, G. I.; Yamaoka,
Y.; Me´graud, F.; Otto, K.; Reichard, U.; Katzowitsch, E.; Wang, X.;
Achtman, M.; Suerbaum, S. Science 2003, 299, 1582-1585.
(2) Linz, B.; Balloux, F.; Moodley, Y.; Manica, A.; Liu, H.; Roumagnac,
P.; Falush, D.; Stamer, C.; Prugnolle, F.; van der Merwe, S. W.; Yamaoka,
Y.; Graham, D. Y.; Perez-Trallero, E.; Wadstrom, T.; Suerbaum, S.;
Achtman, M. Nature 2007, 445, 915-918.
(3) (a) Warren, J. R.; Marshall, B. J. Lancet 1983, 321, 1273-1275. (b)
Marshall, B. J.; Armstrong, J. A.; McGechie, D. B.; Glancy, R. J. Med. J.
Aust. 1985, 142, 436-439. (c) Japanese scientists also found the relation-
ships between bacteria and stomach inflammation about 90 years ago: Kasai,
K.; Kobayashi, R. J. Parasitol. 1919, 6, 1-10.
(4) (a) Cave, D. R. Semin. Gastrointest. Dis. 2001, 12, 196-202. (b)
Peek, R. M.; Blaser, M. J., Jr. Nature ReV. Cancer 2002, 2, 28-37.
(5) Ota, H.; Katsuyama, T.; Ishii, K.; Nakayama, J.; Shiozawa, T.;
Tsukahara, Y. Histochem. J. 1991, 23, 22-28.
(6) Hidaka, E.; Ota, H.; Hidaka, H.; Hayama, M.; Matsuzawa, K.;
Akamatsu, T.; Nakayama, J.; Katsuyama, T. Gut 2001, 49, 474-480.
10.1021/jo070669p CCC: $37.00 © 2007 American Chemical Society
Published on Web 07/14/2007
J. Org. Chem. 2007, 72, 6107-6115
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Manabe et al.
R-selectivity in glycosylation reactions near room temperature.
We believed that the preparation, glycosylation, and deprotection
procedures of this novel donor make it an ideal glycosyl donor
for 1,2-cis glycosidic bond formation for 2-amino-2-deoxy
sugars, and thus we expected that this novel glycosyl donor
would prove useful in the synthesis of anti-Helicobacter pylori
oligosaccharides.
The hexasaccharide was synthesized from the nonreducing
end to the reducing end. This strategy should be useful later
for structure-activity relationship studies because the putative
essential structure, R-GlcNAc, is included in all the intermedi-
ates, allowing these intermediates to be screened for biological
activity following deprotection.
FIGURE 1. Structures of the anti-Helicobacter pylori oligosaccharides.
Results and Discussion
is not unique to this O-linked glycoprotein: p-nitrophenyl R-N-
acetylglucosamine also suppresses the growth of bacteria in a
dose dependent manner, although the inhibition is weak. It is
believed that the nonreducing terminal R-1,4-GlcNAc is essential
for growth inhibition of H. pylori and that the antibiotic activity
is due to biosynthesis inhibition of cholesteryl-R-D-glucoside,
an important component of the H. pylori cell membrane. At
present, an anti-H. pylori oligosaccharide is available only as a
recombinant glycoprotein (CD43) form, synthesized using R-1,4-
N-acetylglucosaminyl transferase in Chinese hamster ovary
cells.9,10 Since synthesis by enzymatic synthesis is limited in
the amount that can be produced and does not allow for
structural variations of the hexasaccharide, the validation of these
biological hypotheses is difficult. A facile and efficient strategy
for chemically synthesizing this hexasaccharide and its deriva-
tives would therefore provide a powerful tool for elucidating
the biosynthesis of cholesteryl-R-D-glucoside inhibition mech-
anism central to its antibacterical activity and facilitate structure-
activity relationship studies.
The stereoselective 1,2-cis glycosylation reaction of the
2-amino-2-deoxy sugar was a crucial problem in the synthesis
of anti-Helicobacter pylori oligosaccharide 1b. To date, the
stereoselective glycosylation of 1,2-cis glycosides remains the
principal challenge in complex oligosaccharide syntheses.11,12
In particular, there has been little progress in devising strategies
for the 1,2-cis stereoselective glycosylation of 2-amino-2-deoxy
sugars since Lemieux and Paulsen introduced an azido moiety
at the 2-position as a nonparticipating group about 30 years
ago.13,14 Recently, we reported several 1,2-cis-selective glycosyl
donors for 2-amino-2-deoxy sugars.15,16 The N-benzyl-2,3-
oxazolidinone group carrying glycosyl donors shows high
The R-selective glycosylation reaction was carried out using
cyclic carbamate donor 215 and galactosyl phenyl thioglycoside
3a17 by AgOTf activation (Scheme 1) in dioxane-toluene near
room temperature.18 The moderate yield of 4a (56%) was due
to a side reaction in which the aglycon thiophenyl group was
transferred from 3a to activated donor 2 (Scheme 2). The
aglycon-transferred R-phenyl thioglycoside 5 was isolated as a
byproduct. This aglycon transfer is considered to proceed via
sulfonium ion intermediate.
To prevent this problem, we used 2,6-dimethylphenyl thiogly-
coside 3b, recently reported by Gindersleeve.19 Acceptor 3b was
prepared from the reported benzylidene compound 619 (Scheme
3); following acetylation, subsequent reductive benzylidene
cleavage gave 2,6-dimethylphenyl thioglycoside 3b in 84%
yield. Using 3b, complete chemoselective glycosylation was
performed again under the same reaction conditions to provide
disaccharide 4b in 92% yield (Scheme 1). In both glycosylation
reactions, the corresponding â-products were not observed by
400 MHz 1H NMR after gel filtration column chromatography
of the crude material.
Subsequently, thioglycoside 4b was directly activated by
N-(phenylthio)-ꢀ-caprolactam-Tf2O20 in the presence of the less
reactive glycosyl acceptor, 4-OH of the glucosamine derivative
8,21 to afford trisaccharide 9 in 77% yield (Scheme 4).
Thioglycoside 4a was activated similarly and gave trisaccharide
9 in 75% yield under the same conditions applied to donor 4b
and 8. Oxidative removal of the p-methoxyphenyl group of 9
(14) Reviews for 1,2-cis glycosylations with 2-amino-2-deoxy sugars:
(a) Banoub, J.; Boullanger, P.; Lafont, D. Chem. ReV. 1992, 92, 1167-
1195.
(15) Manabe, S.; Ishii, K.; Ito, Y. J. Am. Chem. Soc. 2006, 128, 10666-
(7) Kawakubo, M.; Ito, Y.; Okimura, Y.; Kobayashi, M.; Sakura, K.;
Kasama, S.; Fukuda, M. N.; Fukuda, M.; Katsuyama, T.; Nakayama, J.
Science 2004, 305, 1003-1007.
(8) Identification of R-1,4-GlcNAc carrying oligosaccharide; van Hal-
beek, H.; Dorland, L.; Vliegenthart, J. F. G.; Kochetkov, N. K.; Arbatsky,
N. P.; Derevitskaya, V. A. Eur. J. Biochem. 1982, 127, 21-29.
(9) Nakayama, J.; Yeh, J-C.; Misra, A. K.; Ito, S.; Katsuyama, T.; Fukuda,
M. Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 8991-8996.
(10) Nakayama, J.; Kawakubo, M.; Fukuda, M.; Katsuyama, T. PCT
Patent Appl. WO 2005/081904.
10667.
(16) For glycosyl donors with 2,3-oxazolidinone group: (a) Benakli, K.;
Zha, C.; Kerns, R. J. J. Am. Chem. Soc. 2001, 123, 9461-9462; (b) Kerns,
R. J.; Zha, C.; Benakli, K.; Liang, Y.-Z. Tetrahedron Lett. 2003, 44, 8069-
8072; (c) Wei, P.; Kerns, R. J. Tetrahedron Lett. 2005, 46, 6901-6905;
(d) Boysen, M.; Gemma, E.; Lahmann, M.; Oscarson, S. Chem. Commun.
2005, 3044-3046; (e) Wei, P.; Kerns, R. J. J. Org. Chem. 2005, 70, 4195-
4198; (f) Bohn, M. L.; Colombo, M. I.; Stortz, C. A.; Ru´veda, E. A.
Carbohydr. Res. 2006, 341, 1096-1104; (g) 2,3-oxazolidinone carrying
sugar as a good acceptor: Crich, D.; Vinod, A. U. J. Org. Chem. 2005, 70,
1291-1296.
(17) Stahl, W.; Ahlers, M.; Walch, A.; Bartnik, E.; Kretzschmar, G.;
Grabley, S.; Schleyerbach, R.; Eur. Pat. Appl., EPXXDW, EP 601417, 1994.
(18) Demchenko, A. V.; Stauchi, T.; Boons, G-J. Synlett. 1997, 818-
820.
(19) Li, Z.; Gildersleeve, J. C. J. Am. Chem. Soc. 2006, 128, 11612-
11619.
(11) For reviews of 1,2-cis glycosylation: (a) Demchenko, A. V. Synlett.
2003, 1225-1240. (b) Demchenko, A. V. Curr. Org. Chem. 2003, 7, 35-
79. (c) Fairbanks, A. J. Synlett. 2003, 1945-1958.
(12) Recent reports for novel methodology of 1,2-cis glycosylations: (a)
Kim, J-H.; Yang, H.; Boons, G-J. Angew. Chem. Int. Ed. 2005, 44, 947-
949; (b) Kim, J-H.; Yang, H.; Park, J.; Boons, G-J. J. Am. Chem. Soc.
2005, 12, 12090-12097.
(13) (a) Paulsen, H.; Kolar, C.; Stenzel. W. Chem. Ber. 1978, 111, 2358-
2369; (b) Lemieux, R. U.; Ratcliffe, R. M. Can. J. Chem. 1979, 57, 1244-
1251.
(20) Duron, S. G.; Polat, T.; Wong, C.-H. Org. Lett. 2004, 6, 839-841.
(21) Nakano, T.; Ito, Y.; Ogawa, T. Carbohydr. Res. 1993, 243, 43-
69. Now, compound 8 was commercially available from TCI.
6108 J. Org. Chem., Vol. 72, No. 16, 2007

Oligosaccharide Antibiotic ActiVe against H. pylori
SCHEME 1. 1,2-Cis Stereoselective Glycosylation Using an N-Benzyloxazolidinone-Carrying Glycosyl Donor
SCHEME 2. Migration of the Thiophenyl Group
SCHEME 3. Preparation of 2,6-Dimethylphenyl Thioglycoside 3b
was achieved using ceric ammonium nitrate in water to afford
exclusively â-hemiacetal 10, which was subsequently converted
into trichloroacetimidate donor 11 in 82% overall yield for the
two steps. Similarly, the bottom part of trisaccharide 13 was
prepared in 65% yield from disaccharide 4b and O-methyl
galactosamine derivative 12.22 The completely regioselective
reductive opening of the benzylidene group of 13 by Cu(OTf)2-
described cyclic carbamate-equipped glycosyl donor, 2. All
glycosylation reactions were achieved in complete stereoselec-
tivities including the 1,2-cis glycosylation of amino sugar. The
establishment of a facile methodology for the synthesis of 1b,
together with the recent cloning of cholesteryl R-glucosyl
transferase,24,25 means that the structure-activity relationship
of 1 against H. pylori can now be rigorously investigated.25 This
is important because strains of H. pylori resistant to antibiotics
that inhibit bacterial protein biosynthesis have been reported.26
It has also been reported that intrinsic R-glucosylation of
cholesterol abrogates phagocytosis of H. pylori and subsequent
T cell activation.27 It might be possible to develop a novel drug
candidate that produces minimal side effects and is specific
against H. pylori: first, because the putative target, cholesteryl
R-glucosides, have only been detected in H. pylori and Achole-
plasma axanthum28 and second, because few proteins encoded
in other bacterial species such as Clostridium thermocellum and
Lactobacillus johnsonii are homologous to H. pylori cholsteryl
glucosyl transferase.25,29
23
BH3 afforded trisaccharide acceptor 14 in 76% yield. When
0.05 equiv of Cu(OTf)2 was used as described, the yield of 14
was only 22%, and unidentified byproducts were generated.
Increasing the amount of Cu(OTf)2 up to 0.5 equiv gave better
yields.
The final glycosylation reaction was performed using imidate
11 and acceptor 14 in the presence of BF3‚OEt2 (Scheme 5) at
-20 °C to give the hexasaccharide 15 in 83% yield.
Deprotected hexasaccharide 1b was obtained after stepwise
deprotection of 15 (Scheme 6). The phthalimide group was
removed by N,N′-ethylenediamine in BuOH at 90 °C to give
16. The cyclic carbamate group was not opened by this treatment
and was subsequently removed under alkaline conditions. After
both the N- and O-benzyl groups were removed by hydro-
genolysis, selective N-acetylation using Ac2O in MeOH gave
hexasaccharide 1b in 57% overall yield in the four steps.
(24) Lebrun, A-H.; Christian, W.; Hildebrand, J.; Chunin, Y.; Za¨hringer,
U.; Lindner, B.; Meyer, T. F.; Heinz, E.; Warnecke, D. J. Biol. Chem. 2006,
281, 27765-27772.
(25) During our manuscript preparation, it was reported that R-GlcNAc
having pentasaccharide inhibits Helicobacter pylori cholesterol R-glucosyl
transferase: Lee, H.; Kobayashi, M.; Wang, P.; Nakayama, J.; Seeberger,
P. H.; Fukuda, M. Biochem. Biophys. Res. Commun. 2006, 349, 1235-
1241.
Conclusion
We have achieved the first total synthesis of an anti-
Helicobacter pylori oligosaccharide, compound 1b, which is
completed with high overall efficancy by employing a previously
(26) Me´graud, F. Gut 2004, 53, 1374-1384.
(27) Wunger, C.; Churin, Y.; Winau, F.; Warnecke, D.; Vieth, M.;
Lindner, B.; Za¨hringer, U.; Mollenkopf, H.-J.; Heinz, E.; Meyer, T. F. Nat.
Med. 2006, 12, 1030-1038.
(22) Komarova, B. S.; Tsvetkov, Y. E.; Knirel, Y. A.; Za¨hringer, U.;
Pier, G. B.; Nifantiev, N. E. Tetrahedron Lett. 2006, 47, 3583-3587.
(23) Shie, C-R.; Tzeng, Z-H.; Kulkami, S. S.; Uang, B-J.; Hsu, C-Y.;
Hung, S-C.; Angew. Chem,. Int. Ed. 2005, 44, 1665-1668.
(28) Mayberry, W. R.; Smith, P. F. Biochim. Biophys. Acta. 1983, 752,
434-443.
(29) Closridium thermocellum (41% identity); Lactocacillus johnsonii
(35% identity).
J. Org. Chem, Vol. 72, No. 16, 2007 6109

Manabe et al.
SCHEME 4. The Synthesis of Trisaccharides
Hz, 1 H, H-2), 5.47 (s, 1 H, acetal-CHPh), 4.95 (dd, J2,3 ) 10.0
Structure-activity relationship study will be reported in due
course.
Hz, J3,4 ) 3.5 Hz, 1 H, H-3), 4.48 (d, 1 H, H-1), 4.35 (dd, J4,5
)
1.0 Hz, 1 H, H-4), 4.18 (dd, J5,6a ) 1.5 Hz, J6a,6b ) 12.5 Hz, 1 H,
H-6a), 3.95 (dd, J5,6b ) 1.5 Hz, 1 H, H-6b), 3.34 (d, 1 H, H-5),
2.57 (s, 6 H, 2 CH3), 2.14 and 2.08 (s, 3 H each, COCH3); 13C
NMR (125 MHz, CDCl3) δ: 170.7 (COCH3), 169.4 (COCH3),
144.3, 137.5, 131.4, 129.1, 128.2 and 126.4 (aromatic C), 101.0
(acetal-CHPh), 88.5 (C-1), 73.4 (C-4), 73.0 (C-3), 69.3 (C-5), 69.1
(C-6), 67.8 (C-2), 22.4 (2 C, 2 CH3), 20.9 (COCH3), 20.8 (COCH3).
Anal. Calcd for C25H28O7S: C, 63.54; H, 5.97. Found: C, 63.61;
H, 5.91.
Compound 3b. A solution of hydrogen chloride in 1,4-dioxane
(4 M; 28 mL) was added to an ice-cold mixture of the 4,6-O-
benzylidene acetal 7 (4.4 g, 9.31 mmol), sodium cyanoborohydride
(7.2 g, 111.7 mmol), and molecular sieves 3 Å (3.0 g) in THF (70
mL) containing methyl orange as a pH indicator. The deep red
Experimental Section
NMR peak assignments including the identification of the residue
connection were carried out by DQF (double-quantum-filtered)-
COSY, HMBC, and HMQC experiments.
Compound (7). A diol 2,6-dimethylphenyl 4,6-O-benzylidene-
1-thio-â-D-galactopyranoside 6 (3.0 g, 7.72 mmol) was acetylated
with Ac2O-pyridine (1:2, 30 mL) at room temperature overnight.
The mixture was concentrated with toluene several times to give a
crystalline residue. Crystallization of the residue from EtOAc/
24
hexane gave 7 (3.3 g, 90%). Mp 184-185 °C. [R]D +18 (c 1.0,
CHCl3). 1H NMR (500 MHz, CDCl3) δ: 7.55-7.36 (m, 5 H,
aromatic H), 7.26-7.11 (m, 3 H, aromatic H), 5.47 (t, J1,2 ) 10.0
6110 J. Org. Chem., Vol. 72, No. 16, 2007

Oligosaccharide Antibiotic ActiVe against H. pylori
SCHEME 5. The Hexasaccharide Synthesis
SCHEME 6. The Deprotection Sequence To Provide 1b
mixture was stirred for 30 min and then filtered through Celite.
The filtrate was diluted with EtOAc and washed with 1 M HCl.
The separated aqueous layer was extracted with EtOAc. The
combined organic extracts were washed with water and brine, dried
(Na2SO4), filtered, and concentrated. Purification by flash column
chromatography on silica gel (4:1, CHCl3-EtOAc) gave 3b (3.7
g, 84%) which was crystallized from Et2O/hexane. Mp 117-118
(COCH3), 169.6 (COCH3), 144.0, 137.5, 131.3, 129.2, 128.4, 128.2,
127.8 and 127.6 (aromatic C), 88.9 (C-1), 76.6 (C-5), 74.5 (C-3),
73.7 (CH2Ph), 69.5 (C-6), 68.3 (C-2), 68.2 (C-4), 22.4 (2 C, 2 CH3),
20.9 and 20.8 (COCH3). Anal. Calcd for C25H30O7S: C, 63.27; H,
6.37. Found: C, 62.97; H, 6.29.
Compound 4a. To an ice-cold suspension of 2,6-di-tert-butyl-
4-methylpyridine (DTBMP; 0.49 g, 2.38 mmol), silver trifluo-
romethanesulfonate (AgOTf; 0.76 g, 2.97 mmol), and molecular
sieves 4 Å (2.0 g) in 1,4-dioxane-toluene (3:1, 20 mL) was added
a mixture of N-benzyl-6-O-benzyl-2,3,-N,O-carbonyl-4-O-chloro-
acetyl-2-deoxy-R-D-glucopyranosyl bromide 2 (1.04 g, 1.98 mmol)
and phenyl 2,3-di-O-acetyl-6-O-benzyl-1-thio-â-D-galactopyrano-
side 3a (0.59 g, 1.32 mmol) in 1,4-dioxane-toluene (3:1, 20 mL)
via a cannula. The stirring mixture was allowed to warm to room
temperature and stirred for 1 day. The mixture was diluted with
24
1
°C. [R]D +14 (c 1.0, CHCl3). H NMR (500 MHz, CDCl3) δ:
7.35-7.10 (m, 8 H, aromatic H), 5.41 (t, J1,2 ) 10.5 Hz, 1 H, H-2),
4.93 (dd, J2,3 ) 9.5 Hz, J3,4 ) 3.0 Hz, 1 H, H-3), 4.53 and 4.50 (d,
J ) 12.0 Hz, 1 H each, CH2Ph), 4.41 (d, 1 H, H-1), 4.15 (br t,
JH-4,4-OH ) 4.0 Hz, 1 H, H-4), 3.73 (dd, J5,6a ) 5.0 Hz, J6a,6b
)
11.0 Hz, 1 H, H-6a), 3.66 (dd, J5,6b ) 5.0 Hz, 1 H, H-6b), 3.52 (br
t, 1 H, H-5), 2.75 (d, 1 H, 4-OH), 2.54 (s, 6 H, 2 CH3), 2.12 and
2.11 (s, 3 H each, COCH3); 13C NMR (125 MHz, CDCl3) δ: 170.2
J. Org. Chem, Vol. 72, No. 16, 2007 6111

Manabe et al.
EtOAc and filtered through Celite. The filtrate was washed with
saturated aqueous NaHCO3. The separated aqueous layer was
extracted with EtOAc. The combined organic extracts were washed
with brine, dried (Na2SO4), filtered, and concentrated. Purification
by flash column chromatography (3:2, hexane-EtOAc) gave an
3), 73.6 (CH2Ph), 71.2 (C-5), 69.9 (C-4), 67.2 (C-6), 59.6 (C-2),
47.9 (N-CH2Ph), 40.3 (COCH2Cl). Anal. Calcd for C29H28-
ClNO6S: C, 62.87; H, 5.09; N, 2.53. Found: C, 62.65; H, 5.05;
N, 2.42.
Compound 9. Using Compound 4a as a Glycosyl Donor. To
a mixture of donor 4a (410 mg, 0.46 mmol), acceptor 8 (411 mg,
0.69 mmol), N-(phenylthio)-ꢀ-caprolactam (102 mg, 0.46 mmol),
and molecular sieves 4 Å (3.0 g) in CH2Cl2 was added Tf2O (78
µL, 0.46 mmol) slowly at -20 °C. After the mixture was stirred at
-20 °C for 45 min, the mixture was quenched with saturated
aqueous NaHCO3 and filtered through Celite. The filtrate was
extracted with CHCl3. The combined organic extracts were washed
with water, dried (Na2SO4), filtered, and concentrated. Purification
by flash column chromatography (4:3 f 5:4, hexane-EtOAc) gave
compound 9 (477 mg, 75%) as a colorless foam.
Using Compound 4b as a Glycosyl Donor. To a mixture of
donor 4b (1.45 g, 1.58 mmol), acceptor 8 (1.41 g, 2.37 mmol),
N-(phenylthio)-ꢀ-caprolactam (0.35 g, 1.58 mmol), and activated
molecular sieves 4 Å (4.0 g) in CH2Cl2 (40 mL) was added Tf2O
(0.27 mL, 0.46 mmol) slowly at 4 °C. After the ice-cold mixture
was stirred for 1 h, the mixture was worked-up in a manner similar
to that described above for preparation of 9 using 4a. Purification
by flash column chromatography (4:3, hexane-EtOAc) gave 9 (1.68
mg, 77%) as a colorless foam. [R]D27 +51 (c 1.0, CHCl3). 1H NMR
(500 MHz, CDCl3) δ: 7.68-7.01 (m, 33 H, aromatic H), 5.59 (d,
24
R-linked disaccharide 4a (645 mg, 56%) as a colorless foam. [R]D
1
-30 (c 0.83, CHCl3). H NMR (500 MHz, CDCl3) δ: 7.50-7.05
II II
(m, 20 H, aromatic H), 5.33 (t, J4
) 9.5 Hz, 1 H, H-4II), 5.08
,5
(t, J2 ,3I ) 10.5 Hz, 1 H, H-2I), 4.92 (dd, J3 ,4I ) 2.5 Hz, 1 H, H-3I),
I
I
II II
4.90 (d, J1
) 3.0 Hz, 1 H, H-1II), 4.87 and 3.92 (d, J ) 14.5
,2
I
Hz, 1 H each, N-CH2Ph), 4.64 (d, J1 ,2I ) 9.5 Hz, 1 H, H-1I), 4.59
and 4.51 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.49 and 4.33 (d, J
II II
) 12.0 Hz, 1 H each, CH2Ph), 4.23 (d, 1 H, H-4I), 4.19 (dd, J2
,3
II II
) 12.0 Hz, J3
) 10.5 Hz, 1 H, H-3II), 3.99 and 3.89 (d, J )
,4
14.5 Hz, 1 H each, COCH2Cl), 3.87 (m, 1 H, H-5I), 3.79 (dddd,
II II
II II
I
J5
) J5
) 3.0 Hz, 1 H, H-5II), 3.74 (dd, J5 ,6Ia ) 8.5 Hz,
I I
,6
a
,6
b
J6 a,6 b ) 10.0 Hz, 1 H, H-6Ia), 3.66 (dd, J5 ,6 b ) 6.0 Hz, 1 H,
I
I
H-6Ib), 3.45 (dd, J6
) 11.0 Hz, 1 H, H-6IIa), 3.38 (dd, 1 H,
II II
a,6
b
H-6IIb), 3.20 (dd, 1 H, H-2II), 2.09 and 1.92 (s, 3 H each, COCH3);
13C NMR (125 MHz, CDCl3) δ: 170.3 (COCH3), 169.1 (COCH3),
165.6 (oxazolidinone, CdO), 158.4 (COCH2Cl), 137.1, 134.6,
134.1, 129.7 and 129.1-127.9 (aromatic C), 96.7 (C-1II), 84.6 (C-
1I), 76.0 (C-5I), 75.8 (C-4I), 74.1 (C-3I), 73.7 (CH2Ph), 73.5 (CH2-
Ph), 72.9 (C-3II), 71.4 (C-5II), 70.2 (C-4II), 66.9 (C-2I), 66.7 (C-
6II), 55.5 (C-6I), 59.7 (C-2II), 47.2 (N-CH2Ph), 40.4 (COCH2Cl),
20.9 (COCH3), 20.8 (COCH3). Anal. Calcd for C46H48ClNO13S:
C, 62.05; H, 5.43; N, 1.57. Found: C, 61.90; H, 5.33; N, 1.64.
Compound 4b. To an ice-cold suspension of DTBMP (0.39 g,
1.90 mmol), AgOTf (0.61 g, 2.37 mmol), and molecular sieves 4
Å (2.0 g) in 1,4-dioxane-toluene (3:1, 20 mL) was added a mixture
of donor 2 (0.83 g, 1.58 mmol) and acceptor 3b (0.5 g, 1.05 mmol)
in 1,4-dioxane-toluene (3:1, 20 mL) via a cannula. After addition,
the ice-bath was removed. The mixture was stirred at room
temperature overnight. The work-up was achieved in the same
manner as described for 4a. Purification by flash column chroma-
tography (3:2, hexane-EtOAc) gave an R-linked disaccharide 4b
(896 mg, 93%) as a colorless foam. [R]D27 +33 (c 1.0, CHCl3). 1H
NMR (500 MHz, CDCl3) δ: 7.34-7.07 (m, 18 H, aromatic H),
I
III
J1 ,2I ) 8.5 Hz, 1 H, H-1I), 5.36 (t, J4 III ) 10.0 Hz, 1 H, H-4III),
,5
II II
II II
5.14 (dd, J1
) 8.0 Hz, J2
) 11.0 Hz, 1 H, H-2II), 4.89 (d,
,2
,3
III
J1 III ) 3.0 Hz, 1 H, H-1III), 4.78 and 4.50 (d, J ) 12.5 Hz, 1 H
,2
each, CH2Ph), 4.76 (dd, J3 II ) 2.5 Hz, 1 H, H-3II), 4.76 and 4.51
II
,4
(d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.73 and 3.83 (d, J ) 15.0 Hz,
1 H each, N-CH2Ph), 4.67 (d, 1 H, H-1II), 4.51 and 4.35 (d, J )
12.0 Hz, 1 H each, CH2Ph), 4.49 (dd, J2 III ) 12.0 Hz, J3
)
III
III III
,3
,4
10.5 Hz, 1 H, H-3III), 4.45 (s, 2 H, CH2Ph), 4.40 (dd, J2 ,3I ) 11.0
I
I
I
I I
Hz, 1 H, H-2I), 4.30 (dd, J3 ,4 ) 8.5 Hz, 1 H, H-3I), 4.14 (t, J4 ,5
III III
) 9.5 Hz, 1 H, H-4I), 4.14 (d, 1 H, H-4II), 4.02 (dddd, J5
)
,6
a
III III
) 3.0 Hz, 1 H, H-5III), 3.80 (br s, 2 H, H-6Ia and H-6Ib),
5
,6 b
3.70 (s, 3 H, PhOCH3), 3.62 and 3.51 (d, J ) 15.0 Hz, 1 H each,
COCH2Cl), 3.61 (m, 1 H, H-5I), 3.59 (m, 1 H, H-6IIa), 3.56 (m, 1
H, H-5II), 3.55 (m, 1 H, H-6IIIa), 3.45 (m, 2 H, H-6IIb and H-6IIIb),
2.02 and 1.96 (s, 3 H each, COCH3); 13C NMR (125 MHz, CDCl3)
δ: 170.2 (COCH3), 169.1 (COCH3), 165.6 (COCH2Cl), 158.1
(oxazolidinone, CdO), 155.3 (phthalimide, CdO), 150.8 (phthal-
imide, CdO), 138.0, 137.9, 137.2, 137.1, 134.0, 133.8, 131.5,
129.1-127.2, 123.4, 118.7 and 114.3 (aromatic C), 100.3 (C-1I),
97.6 (C-1II), 96.4 (C-1III), 77.8 (C-4I), 76.1 (C-3I), 75.5 (C-4II), 75.0
(C-5I), 74.1 (CH2Ph), 73.6 (CH2Ph), 73.5 (2 C, 2 CH2Ph), 73.4
(C-3III), 72.7 (C-3II), 72.2 (C-5II), 71.5 (C-5III), 70.0 (C-4III), 69.7
(C-2II), 67.6 (C-6I), 66.7 (C-6III), 66.5 (C-6II), 59.7 (C-2III), 55.5
(PhOCH3), 55.5 (C-2I), 47.1 (N-CH2Ph), 40.1 (COCH2Cl), 20.8
(COCH3), 20.7 (COCH3). Anal. Calcd for C75H75ClN2O21: C, 65.47;
H, 5.49; N, 2.04. Found: C, 65.46; H, 5.48; N, 2.00.
Compound 10. Compound 9 (733 mg, 0.53 mmol) was treated
with cerium (IV) ammonium nitrate (CAN; 1.75 g, 3.20 mmol) in
CH3CN-H2O-toluene (8:3:2, 26 mL) on an ice-water bath for
20 min. The mixture was diluted with EtOAc and washed with
water. The separated aqueous layer was extracted with EtOAc. The
combined organic extracts were washed with water and brine, dried
(Na2SO4), filtered and concentrated. Purification by flash column
chromatography (3:2, EtOAc /hexane) gave hemiacetal 10 (603 mg,
II II
I
I
I I
5.43 (t, J4
) 9.5 Hz, 1 H, H-4II), 5.23 (t, J1 ,2 ) J2 ,3 ) 10.5
,5
Hz, 1 H, H-2I), 4.97 (d, J1 II ) 2.5 Hz, 1 H, H-1II), 4.91 (dd, J3 ,4
I
I
I
I
,2
) 2.5 Hz, 1 H, H-3I), 4.89 and 3.98 (d, J ) 15.0 Hz, 1 H each,
N-CH2Ph), 4.71 (dd, J2 II ) 12.0 Hz, J3 II ) 10.5 Hz, 1 H, H-3II),
II
II
,3
,4
4.52 and 4.37 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.48 (s, 2 H,
II II
CH2Ph), 4.47 (d, 1 H, H-1I), 4.23 (d, 1 H, H-4I), 4.08 (dd, J5
,6
a
II II
) J5
) 2.5 Hz, 1 H, H-5II), 4.02 and 3.90 (d, J ) 15.0 Hz, 1
,6
b
I I I I
H each, COCH2Cl), 3.73 (dd, J5 ,6 a ) 8.5 Hz, J6 a,6 b ) 10.0 Hz, 1
I
I
II II
H, H-6Ia), 3.66 (dd, J5 ,6 b ) 5.5 Hz, 1 H, H-5I), 3.54 (dd, J6
a,6
b
) 11.0 Hz, 1 H, H-6IIa), 3.52 (dd, 1 H, H-6Ib), 3.48 (dd, 1 H,
H-6IIb), 3.32 (dd, 1 H, H-2II), 2.53 (s, 6 H, 2 CH3), 2.11 and 1.96
(s, 3 H each, COCH3); 13C NMR (125 MHz, CDCl3) δ: 170.2
(COCH3), 169.3 (COCH3), 165.7 (COCH2Cl), 158.4 (oxazolidinone,
CdO), 144.0, 137.1, 137.1, 134.1, 130.8 and 129.3-127.6 (aromatic
C), 96.6 (C-1II), 88.6 (C-1I), 75.8 (C-5I), 75.6 (C-4I), 73.9 (C-3I),
73.6 (CH2Ph), 73.5 (CH2Ph), 73.2 (C-3II), 71.5 (C-5II), 70.3 (C-
4II), 68.1 (C-2I), 66.9 (C-6I), 66.9 (C-6II), 59.8 (C-2II), 47.2 (N-
CH2Ph), 40.4 (COCH2Cl), 22.4 (2 C, 2 CH3), 20.8 and 20.7
(COCH3). Anal. Calcd for C48H52ClNO13S: C, 62.77; H, 5.71; N,
1.53. Found: C, 62.76; H, 5.75; N, 1.48.
Compound 5. [R]D24 +220 (c 1.0, CHCl3). 1H NMR (500 MHz,
CDCl3) δ: 7.44-7.24 (m, 15 H, aromatic H), 5.41 (d, J1,2 ) 5.0
Hz, 1 H, H-1), 5.40 (t, J3,4 ) 10.5 Hz, 1 H, H-4), 4.81 and 4.17 (d,
J ) 14.5 Hz, 1 H each, N-CH2Ph), 4.57 and 4.19 (d, J ) 11.5 Hz,
1 H each, CH2Ph), 4.44 (dd, J2,3 ) 12.0 Hz, 1 H, H-3), 4.30 (dddd,
J4,5 ) 9.5 Hz, J5,6a ) 2.5 Hz, J5,6b ) 4.0 Hz, 1 H, H-5), 3.97 and
3.89 (d, J ) 15.0 Hz, 1 H each, COCH2Cl), 3.64 (dd, 1 H, H-2),
3.58 (dd, J6a,6b ) 11.0 Hz, 1 H, H-6a), 3.56 (dd, 1 H, H-6b). 13C
NMR (125 MHz, CDCl3) δ 165.6 (COCH2Cl), 157.8 (oxazolidi-
none, CdO), 137.1, 134.1, 132.3, 131.9, 129.3, 129.1, 128.9, 128.6,
128.4, 128.2, 128.1 and 128.0 (aromatic C), 84.8 (C-1), 75.8 (C-
25
1
89%) as a yellow foam. [R]D +54 (c 0.82, CHCl3). H NMR
(500 MHz, CDCl3) δ: 7.73-7.00 (m, 29 H, aromatic H), 5.36 (t,
J4 III ) 9.5 Hz, 1 H, H-4III), 5.31 (t, J1 ,2I ) JH-1 ,1-OHI ) 8.5 Hz,
III
I
I
,5
1 H, H-1I), 5.11 (dd, J1 II ) 7.5 Hz, J2 II ) 10.5 Hz, 1 H, H-2II),
II
II
,2
,3
III III
4.87 (d, J1
) 2.5 Hz, 1 H, H-1III), 4.79 and 4.48 (d, J ) 12.0
,2
Hz, 1 H each, CH2Ph), 4.77 and 4.47 (d, J ) 12.0 Hz, 1 H each,
CH2Ph), 4.72 and 3.82 (d, J ) 14.5 Hz, 1 H each, N-CH2Ph), 4.71
II II
(dd, J3
) 2.5 Hz, 1 H, H-3II), 4.59 (d, 1 H, H-1II), 4.50 and
,4
4.35 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.47 (m, 1 H, H-3III),
4.44 (s, 2 H, CH2Ph), 4.31 (dd, J2 ,3I ) 10.5 Hz, J3 ,4I ) 8.5 Hz, 1
I
I
6112 J. Org. Chem., Vol. 72, No. 16, 2007

Oligosaccharide Antibiotic ActiVe against H. pylori
I
H, H-3I), 4.12 (d, 1 H, H-4II), 4.10 (dd, J4 ,5I ) 9.5 Hz, 1 H, H-4I),
H-3II), 4.85 and 3.92 (d, J ) 14.5 Hz, 1 H each, N-CH2Ph), 4.80
III III III III
III III
III III
4.00 (dddd, J5
) J5
) 3.0 Hz, 1 H, H-5III), 3.80 (dd,
(d, 1 H, H-1II), 4.66 (dd, J2
) 12.0 Hz, J3
) 10.5 Hz, 1
,6
a
I
,6
b
,3
,4
I
I
I
I I
J5 ,6 a ) 3.0 Hz, J6 a,6 b ) 10.5 Hz, 1 H, H-6Ia), 3.76 (dd, J5 ,6 b
)
H, H-3III), 4.56 (s, 2 H, CH2Ph), 4.52 and 4.35 (d, J ) 11.5 Hz, 1
I
I
2.0 Hz, 1 H, H-6Ib), 3.62 and 3.51 (d, J ) 15.0 Hz, 1 H each,
H each, CH2Ph), 4.38 (d, J3 ,4 ) 3.5 Hz, 1 H, H-3I), 4.23 (dd,
I I I I
COCH2Cl), 3.58 (m, 1 H, H-6IIa), 3.56 (m, 1 H, H-5I), 3.54 (m, 1
J5 ,6 a ) 1.5 Hz, J6 a,6 b ) 12.0 Hz, 1 H, H-6Ib), 4.21 (d, 1 H, H-4II),
I III III III III
III III
H, H-6IIIa), 3.51 (m, 1 H, H-5II), 3.45 (dd, J6
) 11.0 Hz, 1
4.11 (dd, J2 ,3I ) 10.5 Hz, 1 H, H-3I), 4.07 (dddd, J5
a ) J5
b
,6
,6 b
) 5.0 Hz, J6 a,6 ) 9.5 Hz, 1 H,
)3.0 Hz, 1 H, H-5III), 3.97 (dd, J5 ,6 b ) 1.5 Hz, 1H, H-6Ib), 3.90
II II
II II
I I
H, H-6IIIb), 3.42 (dd, J5
,6
b
a,6 b
H-6IIb), 3.22 (dd, 1 H, H-2III), 3.09 (d, 1 H, OH-1I), 2.00 and 1.95
(s, 3 H each, COCH3); 13C NMR (125 MHz, CDCl3) δ: 170.2
(COCH3), 169.1 (COCH3), 168.0 (2 C, phthalimide, CdO), 165.6
(COCH2Cl), 158.1 (oxazolidinone, CdO), 138.1, 137.7, 137.2,
137.1, 134.0, 133.8, 131.5, 129.0-127.2 and 123.3 (aromatic C),
100.2 (C-1II), 96.4 (C-1III), 92.8 (C-1I), 77.7 (C-4I), 75.7 (C-3I),
75.5 (C-4II), 74.7 (C-5I), 73.9 (CH2Ph), 73.6 (CH2Ph), 73.5 (3 C,
2 CH2Ph and C-3III), 72.7 (C-3II), 72.1 (C-5II), 71.5 (C-5III), 69.9
(C-4III), 69.6 (C-2II), 67.6 (C-6I), 66.6 (C-6III), 66.5 (C-6II), 59.7
(C-2III), 57.4 (C-2I), 47.1 (N-CH2Ph), 40.1 (COCH2Cl), 20.8
(COCH3), 20.7 (COCH3). Anal. Calcd for C68H69ClN2O20: C, 64.32;
H, 5.48; N, 2.21. Found: C, 64.10; H, 5.50; N, 2.13.
(dd, 1 H, H-2I), 3.87 and 3.74 (d, J ) 14.5 Hz, 1 H each, COCH2-
II II
II II
Cl), 3.86 (br t, J5
) J5
) 7.5 Hz, 1 H, H-5II), 3.77 (dd,
,6
a
,6 b
II II
J6
) 9.5 Hz, 1 H, H-6IIa), 3.64 (dd, 1 H, H-6IIb), 3.64 (br s,
a,6
b
III III
1 H, H-5I), 3.54 (dd, J6
b )11.0 Hz, 1 H, H-6IIIa), 3.46 (dd, 1
a,6
H, H-6IIIb), 3.45 (s, 3 H, OCH3), 3.30 (dd, 1 H, H-2III), 2.03 and
1.95 (s, 3 H each, COCH3); 13C NMR (125 MHz, CDCl3) δ: 170.4
(COCH3), 169.4 (COCH3), 165.7 (COCH2Cl), 158.4 (oxazolidinone,
CdO), 137.5, 137.1, 134.0, 129.2-127.7 and 126.1 (aromatic C),
102.2 (C-1II), 100.8 (acetal-CHPh), 99.5 (C-1I), 96.8 (C-1III), 75.9
(C-4II), 75.8 (C-3I), 75.7 (C-4I), 73.6 (CH2Ph). 73.5 (2 C, C-3III
and CH2Ph), 73.1 (C-3II), 72.5 (C-5II), 71.6 (C-5I), 70.1 (C-4III),
69.0 (C-6I), 68.7 (C-2II), 67.2 (C-6II), 66.5 (C-6III), 62.9 (C-5I), 59.8
(C-2III), 59.0 (C-2I), 55.6 (OCH3), 47.3 (N-CH2Ph), 40.4 (COCH2-
Cl), 20.9 (COCH3), 20.7 (COCH3). Anal. Calcd for C54H59-
ClN4O18: C, 59.64; H, 5.47; N, 5.15. Found: C, 59.73; H, 5.49;
N, 4.98.
Compound 11. To an ice-cold mixture of hemiacetal 10 (358
mg, 0.28 mmol) and trichloroacetonitrile (0.28 mL, 2.80 mmol) in
CH2Cl2 (6 mL) was added 0.32 M solution of 1,8-diazabicyclo-
[5.4.0]undec-7-ene (DBU) in CH2Cl2 (88 µL, 0.028 mmol). After
the mixture was stirred for 10 min, the mixture was purified directly
by flash column chromatography (1:1, hexane-EtOAc) to give
Compound 14. To a solution of compound 13 (674 mg, 0.62
mmol) in CH2Cl2 (15 mL) were added BH3‚THF in THF (1 M;
3.1 mL, 3.10 mmol) and copper(II) trifluoromethanesulfonate (112
mg, 0.31 mmol). After being stirred for 30 min at room temperature,
the mixture was cooled on an ice-water bath, quenched by
sequential addition of triethylamine (68 µL, 0.62 mmol) and
methanol. The mixture was filtered through Celite. The filtrate was
washed with water and the separated aqueous layer was extracted
with CHCl3. The combined organic extracts were washed with brine,
dried (Na2SO4), filtered and concentrated. Purification by flash
column chromatography on silica gel (3:2, CHCl3-EtOAc) gave
14 (512 mg, 76%) as a colorless foam. [R]D24 +53 (c 1.0, CHCl3).
1H NMR (500 MHz, CDCl3) δ: 7.39-7.05 (m, 20 H, aromatic
25
compound 11 (366 mg, 92%) as a pale yellow foam. [R]D +70
1
(c 0.66, CHCl3). H NMR (500 MHz, CDCl3) δ: 8.53 [s, 1 H,
I
I
C(NH)CCl3], 7.67-7.01 (m, 29 H, aromatic H), 6.36 (d, J1 ,2
)
9.0 Hz, 1 H, H-1I), 5.36 (t, J4 III ) 9.5 Hz, 1 H, H-4III), 5.12 (dd,
III
,5
II II
II II
III III
J1
) 8.0 Hz, J2
) 11.0 Hz, 1 H, H-2II), 4.88 (d, J1
)
,2
,3
,2
2.5 Hz, 1 H, H-1III), 4.80 and 4.51 (d, J ) 12.5 Hz, 1 H each,
CH2Ph), 4.77 and 4.51 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.73
II II
and 3.84 (d, J ) 15.0 Hz, 1 H each, N-CH2Ph), 4.37 (dd, J3
)
3.0 Hz, 1 H, H-3II), 4.64 (d, 1 H, H-1II), 4.51 and 4.35 (d, J ),411.5
Hz, 1 H each, CH2Ph), 4.48 (dd, J2 III ) 12.0 Hz, J3 III ) 10.0
III
III
,3
,4
Hz, 1 H, H-3III), 4.47 and 4.45 (d, J ) 11.5 Hz, 1 H each, CH2Ph),
4.44 (dd, J2 ,3I ) 10.5 Hz, 1 H, H-2I), 4.34 (t, J3 ,4I ) 10.0 Hz, 1 H,
H), 5.37 (t, J4
) 9.5 Hz, 1 H, H-4III), 5.28 (dd, J1
) 7.5
I
I
III III
II II
,5
,2
I
I
II II
III III
H-3I), 4.20 (t, J4 ,5 ) 10.0 Hz, 1 H, H-4I), 4.13 (d, 1 H, H-4II),
Hz, J2
) 10.5 Hz, 1 H, H-2II), 4.95 (d, J1
) 2.5 Hz, 1 H,
,3
,2
III III
III III
I I
4.01 (dddd, J5
a ) J5
b ) 3.5 Hz, 1 H, H-5III), 3.83 (d, J5 ,6 a
H-1III), 4.91 and 4.57 (d, J ) 11.0 Hz, 1 H each, CH2Ph), 4.90
,6
,6
I
I
II
) J5 ,6 b ) 2.5 Hz, 2 H, H-6Ia and H-6Ib), 3.71 (dddd, 1 H, H-5I),
(dd, J3 II ) 2.5 Hz, 1 H, H-3II), 4.84 and 3.98 (d, J ) 15.0 Hz, 1
,4
I
I
3.60 and 3.49 (d, J ) 15.0 Hz, 1 H each, COCH2Cl), 3.59 (m, 1
H, N-CH2Ph), 4.83 (d, J1 ,2 ) 3.0 Hz, 1 H, H-1I), 4.82 (d, 1 H,
III III
H, H-6IIa), 3.55 (dd, J6
b ) 11.0 Hz, 1 H, H-6IIIa), 3.53 (m, 1
H-1II), 4.67 and 4.58 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.52 (dd,
a,6
III III
III III
H, H-5II), 3.45 (dd, 1 H, H-6IIIb), 3.45 (m, 1 H, H-6IIb), 3.22 (dd,
1 H, H-2III), 2.02 and 1.96 (s, 3 H each, COCH3); 13C NMR (125
MHz, CDCl3) δ: 170.2 (COCH3), 169.1 (COCH3), 168.0 and 167.4
(broadened each, phtalimide, CdO), 165.6 (COCH2Cl), 160.9
[C(NH)CCl3], 158.1 (oxazolidinone, CdO), 138.0, 137.8, 137.2,
137.1, 134.0, 133.9, 131.3, 129.1-127.3 and 123.3 (aromatic C),
100.1 (C-1II), 96.4 (C-1III), 94.0 (C-1I), 90.3 [C(NH)CCl3], 77.3
(C-4I), 75.8 (2 C, C-3I and C-5I), 75.5 (C-4II), 74.0 (CH2Ph), 73.5
(4 C, 3 CH2Ph and C-3III), 72.7 (C-3II), 72.1 (C-5II), 71.5 (C-5III),
69.9 (C-4III), 69.6 (C-2III), 67.1 (C-6I), 66.7 (C-6III), 66.5 (C-6II),
59.7 (C-2III), 54.4 (C-2I), 47.1 (N-CH2Ph), 40.1 (COCH2Cl), 20.8
(COCH3), 20.7 (COCH3). Anal. Calcd for C70H69Cl4N3O20: C,
59.45; H, 4.92; N, 2.97. Found: C, 59.20; H, 4.96; N, 2.93.
Compound 13. To a mixture of donor 4b (877 mg, 0.96 mmol),
acceptor 12 (352 mg, 1.15 mmol), N-(phenylthio)-ꢀ-caprolactam
(211 mg, 0.96 mmol), and molecular sieves 4 Å (3.0 g) in CH2Cl2
(20 mL) was added Tf2O (162 µL, 0.96 mmol) slowly at 4 °C.
After the chilled mixture was stirred for 30 min, the mixture was
warmed to room temperature and stirred for 30 min. Then the
mixture was worked-up in a manner similar to that described for
9. The crude mixture was purified by flash column chromatography
(1:1, hexane-EtOAc) to give 13 (674 mg, 65%) as a colorless foam.
[R]D27 +89 (c 1.0, CHCl3). 1H NMR (500 MHz, CDCl3) δ: 7.50-
7.07 (m, 20 H, aromatic H), 5.52 (s, 1 H, acetal-CHPh), 5.42 (t,
J2
) 11.5 Hz, J3
) 11.5 Hz, 1 H, H-3III), 4.51 and 4.34
,3
,4
(d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.25 (d, 1 H, H-4II), 4.07 (dd,
J2 ,3I ) 10.5 Hz, J3 ,4I ) 3.0 Hz, 1 H, H-3I), 4.01 (dddd, J5
)
I
I
III III
,6
a
III III
J5
b ) 2.5 Hz, 1 H, H-5III), 3.96 (br s, 1 H, H-4I), 3.86 (m, 2 H,
,6
H-6IIa and H-5II), 3.81 (dd, 1 H, H-2I), 3.74 (m, 1 H, H-5I), 3.70
II II
II II
(m, 1 H, H-6Ia), 3.64 (dd, J5
) 9.5 Hz, J6
) 13.0 Hz, 1
,6
b
a,6 b
III III
H, H-6II), 3.55 (dd, J6
) 11.0 Hz, 1 H, H-6IIIa), 3.49 (m, 1
a,6
b
H, H-6Ib), 3.47 and 3.39 (d, J ) 15.0 Hz, 1 H each, COCH2Cl),
3.43 (dd, 1 H, H-6IIIb), 3.40 (s, 3 H, OCH3), 3.28 (dd, 1 H, H-2III),
2.09 and 1.97 (s, 3 H each, COCH3); 13C NMR (125 MHz, CDCl3)
δ: 170.4 (COCH3), 169.6 (COCH3), 165.5 (COCH2Cl), 158.3
(oxazolidinone, CdO), 137.7, 137.1, 137.0, 134.0, and 129.2-127.7
(aromatic C), 102.1 (C-1II), 98.9 (C-1I), 96.8 (C-1III), 77.8 (C-3I),
76.1 (C-4I), 76.0 (C-4II), 74.6 (CH2Ph), 73.7 (CH2Ph), 73.6 (C-
3III), 73.4 (CH2Ph), 72.7 (C-3II), 72.4 (C-5II), 71.7 (C-5III), 70.4
(C-5I), 69.7 (C-4III), 69.1 (C-2II), 66.7 (C-6II), 66.4 (C-6III), 62.0
(C-6I), 60.3 (C-2I), 59.8 (C-2III), 55.3 (OCH3), 47.4 (N-CH2Ph),
40.0 (COCH2Cl), 20.8 and 20.7 (COCH3). Anal. Calcd for C54H61-
ClN4O18: C, 59.53; H, 5.64; N, 5.14. Found: C, 59.33; H, 5.69;
N, 4.97.
Compound 15. A solution of BF3‚Et2O in CH2Cl2 (0.1 M; 50
µL, 0.050 mmol) was added to a mixture of donor 11 (359 mg,
0.254 mmol), acceptor 14 (254 mg, 0.233 mmol), and molecular
sieves 4 Å (0.5 g) in CH2Cl2 (10 mL) at -20 °C. After being stirred
for 30 min at -20 °C, the mixture was quenched by addition of
saturated aqueous NaHCO3 and filtered through Celite. The filtrate
was extracted with CHCl3. The combined organic extracts were
J4 III ) 10.0 Hz, 1 H, H-4III), 5.23 (dd, J1 II ) 7.5 Hz, J2
)
III
II
II II
,5
,2
,3
III III
10.5 Hz, 1 H, H-2II), 4.93 (d, J1
) 2.5 Hz, 1 H, H-1III), 4.92
,2
I
I
II II
(d, J1 ,2 ) 3.5 Hz, 1 H, H-1I), 4.85 (dd, J3
) 3.0 Hz, 1 H,
,4
J. Org. Chem, Vol. 72, No. 16, 2007 6113

Manabe et al.
washed with water, dried (Na2SO4), filtered and concentrated.
Purification by flash column chromatography on silica gel (1:1 f
4:3, EtOAc-hexane) gave a hexasaccharide 15 (434 mg, 80%) as a
11.5 Hz, 1 H each, CH2Ph), 4.50 and 4.42 (d, J ) 11.5 Hz, 1 H
Gal′ Gal′
each, CH2Ph), 4.41 (d, J1
) 7.5 Hz, 1 H, H-1Gal′), 4.37 and
,2
GlcN′ GlcN′
4.34 (d, J ) 11.5 Hz, 1 H each, CH2Ph), 4.37 (dd, J2
)
,3
24
1
GlcN′
GlcN GlcN
colorless foam. [R]D +48 (c 1.0, CHCl3). H NMR (500 MHz,
12.0 Hz, J3
GlcN′ ) 9.5 Hz, 1 H, H-3GlcN′), 4.28 (dd, J2
,4
GlcN GlcN
,3
IV IV
II II
CDCl3) δ: 7.66-7.05 (m, 49 H, aromatic H), 5.35 (t, J3
)
) 12.0 Hz, J3
) 9.5 Hz, 1 H, H-3GlcN), 4.20 (d, J1
)
,4
,4
,2
IV IV
VI VI
,4
VI VI
I
I
J4
) 10.0 Hz, 1 H, H-4IV), 5.34 (t, J3
) J4
) 10.0
7.5 Hz, 1 H, H-1II), 4.08 (dd, J2 ,3I ) 10.5 Hz, J3 ,4I ) 3.0 Hz, 1 H,
II II II II
,5
,5
Hz, 1 H, H-4VI), 5.22 (dd, J1 V ) 7.5 Hz, J2 V ) 11.0 Hz, 1 H,
H-3I), 4.06 (br s, 1 H, H-4Gal), 4.03 (t, J3
) J4
) 9.5 Hz, 1
V
V
,2
,3
,4
,5
H-2V), 5.09 (dd, J1 III ) 8.0 Hz, J2 III ) 11.0 Hz, 1 H, H-2III),
H, H-4II), 4.00 (dd, J5 a ) 3.0 Hz, J6 b ) 11.5 Hz, 1 H, H-6IIa),
,
III
III
II II
II II
,2
,3
,6
a 6
II II
VI VI
,2
5.02 (d, J1
) 8.0 Hz, 1 H, H-1II), 4.94 (d, J1
) 2.5 Hz, 1
3.95 (br s, 1 H, H-4Gal’), 3.91 (br s, 1 H, H-4Gal), 3.95-3.90 (m, 3
H, H-5GlcN, H-5GlcN′ and H-5I), 3.84 (dd, 1 H, H-2I), 3.70 (m, 1 H,
H-6IIb), 3.68 (m, 1 H, H-4GlcN), 3.67 (m, 1 H, H-4GlcN′), 3.62 (m,
1 H, H-2Gal), 3.59 (m, 2 H, H-3Gal and H-6Galb), 3.56 (m, 1 H,
H-6Gal′a), 3.49 (m, 1 H, H-2Gal′), 3.46 (m, 1 H, H-5II), 3.71-3.52
(m, 6 H, H-6Ia, H-6Ib, H-6GlcNa, H-6GlcNb, H-6GlcN’a and H-6GlcN′b),
,2
IV IV
V V
H, H-1VI), 4.86 (d, J1
) 3.0 Hz, 1 H, H-1IV), 4.86 (dd, J3
,2
,4
) 3.5 Hz, 1 H, H-3V), 4.86 and 3.96 (d, J ) 15.0 Hz, 1 H each,
N-CH2Ph), 4.84 and 4.45 (d, J ) 11.0 Hz, 1 H each, CH2Ph), 4.77
and 4.41 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.74 and 4.45 (d, J
) 11.5 Hz, 1 H each, CH2Ph), 4.72 and 3.82 (d, J ) 15.0 Hz, 1 H
each, N-CH2Ph), 4.72 (d, 1 H, H-1V), 4.68 (dd, J3
) 3.0 Hz,
3.39 (t, J2 II ) 9.5 Hz, 1 H, H-2II), 3.40 (m, 1 H, H-5Gal′), 3.36 (s,
III III
II
,4
,3
1 H, H-3III), 4.62 and 4.60 (d, J ) 12.0 Hz, 1 H each, CH2Ph),
4.57 (d, 1 H, H-1III), 4.51 and 4.35 (d, J ) 12.0 Hz, 1 H each,
CH2Ph), 4.50 and 4.32 (d, J ) 11.5 Hz, 1 H each, CH2Ph), 4.47
3 H, OCH3), 3.30 (dd, J5
) 5.0 Hz, J6
) 9.5 Hz,
Gal′ Gal′
Gal′ Gal′
,6
b
a,6
b
1 H, H-6Gal′b), 3.29 (m, 1 H, H-3Gal′), 3.11 (dd, 1 H, H-2GlcN′), 3.04
(dd, 1 H, H-2GlcN), 2.80 (dd, 1 H, H-2II). 13C NMR (125 MHz,
CDCl3) δ: 158.8 and 158.6 (oxazolidinone, CdO), 138.8, 138.3,
138.1, 137.5, 137.4 (2 C), 137.3, 134.2 (2 C), 129.1-127.0
(aromatic C), 104.8 (C-1Gal), 103.5 (C-1II), 103.1 (C-1Gal′), 98.7
(C-1I), 96.6 (C-1GlcN), 96.2 (C-1GlcN′), 81.7 (C-3II), 78.6 (C-4Gal),
77.9 (2 C, C-3I and C-4Gal′), 76.9 (C-4II), 76.5 (C-3GlcN′), 76.2 (2
C, C-4I and C-3GlcN), 74.6 (C-5GlcN), 74.5 (C-5II), 74.3 (CH2Ph),
74.2 (C-5GlcN′), 74.0 (CH2Ph), 73.5 (3 C, 2 CH2Ph and C-3Gal′),
73.3 (2 C, C-3Gal and CH2Ph), 73.0 (2 C, 2 CH2Ph), 72.4 (C-5Gal),
72.4 (C-2Gal′), 72.0 (2 C, C-2Gal and C-5Gal′), 69.7 (C-5I), 69.5 (C-
6I), 68.9 (C-4GlcN′), 68.7 (2 C, C-4GlcN and C-6GlcN either C-6GlcN′),
68.6 (C-6GlcN either C-6GlcN′), 67.4 (C-6Gal), 66.8 (C-6Gal′), 59.9 (C-
2I), 59.2 (C-2GlcN′), 58.9 (C-2GlcN), 55.1 (OCH3), 47.2 (N-CH2Ph),
46.7 (N-CH2Ph).
(dd, J2
) 12.0 Hz, 1 H, H-3VI), 4.46 (dd, J2
) 12.0 Hz,
VI VI
IV IV
,3
,3
1 H, H-3IV), 4.44 and 4.41 (d, J ) 11.0 Hz, 1 H each, CH2Ph),
I
I
4.34 (d, J1 ,2 ) 3.0 Hz, 1 H, H-1I), 4.25 (d, 1 H, H-4V), 4.23 (dd,
J2 II ) 10.5 Hz, J3 II ) 8.5 Hz, 1 H, H-3II), 4.12 (d, 1 H, H-4III),
II
II
,3
,4
4.11 (t, J4 II ) 8.5 Hz, 1 H, H-4II), 4.11 (d, 1 H, H-2II), 4.00 (m,
II
,5
I
I
I
I
1 H, H-5IV), 3.98 (m, 1 H, H-5VI), 3.87 (dd, J2 ,3 ) 10.5 Hz, J3 ,4
V
V
V
V
) 2.5 Hz, 1 H, H-3I), 3.84 (t, J5
) J6
) 9.5 Hz, 1 H,
,6
a
a,6 b
H-6Va), 3.81 (m, 1 H, H-6IIa), 3.80 (m, 1 H, H-5V), 3.79 (br s, 1 H,
II II
II II
H-4I), 3.75 (dd, J5 b ) 1.0 Hz, J6
b ) 11.0 Hz, 1 H, H-6IIb),
,6
a,6
I
I
I
I
3.71 (dd, J5 ,6 a ) 3.0 Hz, J6 a,6 b ) 11.5 Hz, 1 H, H-6Ia), 3.64 (m,
1 H, H-5I), 3.64 (m, 1 H, H-6Vb), 3.61 and 3.50 (d, J ) 15.0 Hz,
1 H each, COCH2Cl), 3.60 (dd, 1 H, H-2I), 3.55 (m, 1 H, H-6IIIa),
IV IV
IV IV
3.54 (dd, J5
3.51 (dd, J5
) 2.5 Hz, J6
) 2.5 Hz, J6
) 11.0 Hz, 1 H, H-6IVa),
,6
a
a,6
b
VI VI
,6
VI VI
a,6
) 11.0 Hz, 1 H, H-6VIa),
a
b
Compound 1b. A solution of compound 16 (77 mg, 0.041 mmol)
in 1 M NaOH (4 mL) and 1,4-dioxane (4 mL) was stirred at 80 °C
overnight. The mixture was cooled to room temperature, diluted
with EtOAc, and washed with water. The separated aqueous layer
was extracted with EtOAc. The combined organic extracts were
washed with water and brine, dried (Na2SO4), filtered, and
concentrated. Purification by flash column chromatography on silica
gel (8:1, CHCl3-MeOH) gave a N,O-deacylated intermediate (68
mg, 90%). [R]D24 +54 (c 1.0, CHCl3). 1H NMR (500 MHz, CDCl3)
3.50 and 3.43 (d, J ) 15.0 Hz, 1 H each, COCH2Cl), 3.49 (m, 1
IV IV
H, H-5II), 3.46 (m, 1 H, H-5III), 3.44 (dd, J5
) 2.5 Hz, 1 H,
,6
b
H-6IVb), 3.41 (m, 1 H, H-6Ib), 3.40 (m, 1 H, H-6IIIb), 3.39 (dd,
VI VI
J5
b ) 2.5 Hz, 1 H, H-6VIb), 3.27 (dd, 1 H, H-2VI), 3.21 (dd, 1
,6
H, H-2IV), 2.86 (s, 3 H, OCH3), 2.03, 2.01, 1.95 and 1.95 (s, 3 H
each, COCH3); 13C NMR (125 MHz, CDCl3) δ: 170.3 (COCH3),
170.2 (COCH3), 169.6 (COCH3), 169.1 (COCH3), 167.8 (broadened
each, phthalimide, CdO), 167.4 (broadened each, phthalimide, Cd
O), 165.5 (2 C, 2 COCH2Cl), 158.2 and 158.0 (oxazolidinone, Cd
O), 138.1, 138.0, 137.8, 137.2, 137.1, 137.0, 137.0, 134.0, 134.0,
133.7, 131.5, 129.1-127.1, 123.2 and 122.9 (aromatic C), 102.1
(C-1V), 100.1 (C-1III), 98.8 (C-1II), 98.3 (C-1I), 96.8 (C-1VI), 96.5
(C-1IV), 77.9 (C-3I), 77.5 (C-4II), 76.6 (C-4I), 75.8 (C4V), 75.7 (C-
3II), 75.5 (C-4III), 74.7 (CH2Ph), 74.6 (C-5II), 73.9 (CH2Ph), 73.7
(CH2Ph), 73.6 (CH2Ph), 73.5 (2 C, C-3IV and C-3VI), 73.4 (2 C, 2
CH2Ph), 73.4 (CH2Ph), 72.7 (C-3III), 72.6 (C-3V), 72.2 (C-5V), 71.9
(C-5III), 71.5 (C-5VI), 71.4 (C-5IV), 69.9 (C-4VI), 69.8 (C-4IV), 69.6
(2 C, C-6I and C-2V), 69.4 (C-5I), 69.0 (C-2III), 67.6 (C-6II), 66.6
(2 C, C-6III and C-6V), 66.4 (2 C, C-6IV and C-6VI), 59.9 (C-2I),
59.7 (2 C, C-2IV and C-2VI), 55.6 (C-2II), 54.4 (OCH3), 47.2 and
47.0 (N-CH2Ph), 40.1 (2 C, 2 COCH2Cl), 20.8-20.6 (COCH3).
Anal. Calcd for C122H128Cl2N6O37: C, 62.59; H, 5.51; N, 3.59.
Found: C, 62.31; H, 5.48; N, 3.59.
δ: 7.34-7.15 (m, 45 H, aromatic H), 5.15 and 4.60 (d, J ) 11.5
GlcN′
Hz, 1 H each, CH2Ph), 5.00 (d, J1
GlcN′ ) 3.5 Hz, 1 H, H-1GlcN′),
,2
GlcN
4.89 (d, J1
GlcN ) 3.5 Hz, 1 H, H-1GlcN), 4.88 and 4.55 (d, J )
I I
,2
11.5 Hz, 1 H each, CH2Ph), 4.82 (d, J1 ,2 ) 4.0 Hz, 1 H, H-1I),
4.61 and 4.43 (d, J ) 11.0 Hz, 1 H each, CH2Ph), 4.55 and 4.49
(d, J ) 11.5 Hz, 1 H each, CH2Ph), 4.53 and 4.48 (d, J ) 11.0 Hz,
Gal Gal
1 H each, CH2Ph), 4.50 (d, J1
) 8.0 Hz, 1 H, H-1Gal), 4.40
,2
Gal’ Gal’
and 4.36 (d, J ) 12.0 Hz, 1 H each, CH2Ph), 4.38 (d, J1
)
,2
8.0 Hz, 1 H, H-1Gal’), 4.22 (s, 2 H, CH2Ph), 4.19 (d, J1
) 8.0
II II
,2
Hz, 1 H, H-1II), 4.05 (dd, J2 ,3 ) 10.5 Hz, J3 ,4 ) 3.0 Hz, 1 H,
I
I
I I
H-3I), 4.04 (m, 1 H, H-5GlcN′), 4.00 (t, J3
) J4
) 9.5 Hz, 1
II II
II II
,4
,5
H, H-4II), 3.98 (br s, 1 H, H-4Gal), 3.97 (m, 1 H, H-5GlcN), 3.95 (dd,
II II
II II
J5
) 3.0 Hz, J6
) 11.0 Hz, H-6IIa), 3.92 (m, 1 H, H-5I),
,6
a
a,6 b
3.90 (br s, 1 H, H-4I), 3.84 (dd, 1 H, H-2I), 3.82 (br s, 1 H, H-4Gal′),
3.76 (m, 1 H, H-6GlcNa), 3.76 (m, 1 H, H-6Ia), 3.75 (m, 1 H, H-5Gal),
3.74 (m, 1 H, H-6Gal′a), 3.74 and 3.64 (d, J ) 15.0 Hz, 1 H each,
N-CH2Ph), 3.69 and 3.56 (d, J ) 15.0 Hz, 1 H each, N-CH2Ph),
3.67 (m, 1 H, H-6Ib), 3.65 (m, 1 H, H-2Gal), 3.56 (m, 1 H, H-6Galb),
Compound 16. A solution of compound 15 (102 mg, 0.043
mmol) and N,N′-ethylenediamine (0.5 mL) in BuOH (5 mL) was
stirred at 90 °C overnight. The mixture was concentrated in Vacuo,
and the residue was chromatographed on silica gel with CHCl3-
MeOH (9:1) to give a N-dephthaloylated compound 16 (77 mg,
95%). [R]D25 +26 (c 1.0, CHCl3). 1H NMR (500 MHz, CDCl3) δ:
GlcN GlcN
GlcN GlcN
3.56 (m, 1 H, H-6GlcN′b), 3.53 (dd, J5
b ) 7.5 Hz, J6
,6
a,6
b
Gal′
) 10.0 Hz, H-6GlcNb), 3.49 (dd, J2
Gal′ ) 10.0 Hz, 1 H, H-2Gal′),
,3
GlcN′ GlcN′
GlcN′ GlcN′
3.45 (dd, J2
) 10.0 Hz, J3
,
) 8.5 Hz, 1 H,
,3
4
7.37-7.00 (aromatic H), 5.08 and 4.58 (d, J ) 11.5 Hz, 1 H each,
H-3GlcN′), 3.44 (m, 1 H, H-5II), 3.40 (m, 1 H, H-4GlcN′), 3.38 (t,
GlcN′ GlcN′
II II
II II
CH2Ph), 5.08 (d, J1
) 2.5 Hz, 1 H, H-1GlcN′), 4.97 (d,
J2
) J3
) 9.5 Hz, 1 H, H-3II), 3.38 (m, 1 H, H-5Gal′), 3.38
,2
,3
,4
GlcN
J1
GlcN ) 3.0 Hz, 1 H, H-1GlcN), 4.92 and 4.65 (d, J ) 12.0 Hz,
(s, 3 H, OCH3), 3.35 (m, 1 H, H-4GlcN), 3.34 (m, 1 H, H-3GlcN),
,2
Gal′ Gal′
Gal′ Gal′
1 H each, CH2Ph), 4.83 and 3.91 (d, J ) 15.0 Hz, 1 H each, N-CH2-
3.31 (dd, J5
b ) 4.5 Hz, J6
b ) 8.5 Hz, 1 H, H-6Gal′b),
,6
a,6
Ph), 4.80 and 3.78 (d, J ) 15.0 Hz, 1 H each, N-CH2Ph), 4.78 (d,
3.19 (br m, 1 H, H-3Gal′), 2.79 (dd, 1 H, H-2II), 2.54 (dd, 1 H,
H-2GlcN′), 2.47 (dd, 1 H, H-2GlcN). 13C NMR (125 MHz, CDCl3) δ:
139.7, 139.6, 139.2, 138.4, 138.0, 137.7 (2 C), 137.6, 137.3 and
128.5-127.1 (aromatic C), 104.9 (C-1II), 104.1 (C-1Gal), 103.1 (C-
I
I
J1 ,2 ) 3.5 Hz, 1 H, H-1I), 4.65 and 4.45 (d, J ) 12.0 Hz, 1 H
each, CH2Ph), 4.58 and 4.54 (d, J ) 11.0 Hz, 1 H each, CH2Ph),
Gal Gal
4.56 (d, J1
) 7.5 Hz, 1 H, H-1Gal), 4.52 and 4.42 (d, J )
,2
6114 J. Org. Chem., Vol. 72, No. 16, 2007

Oligosaccharide Antibiotic ActiVe against H. pylori
IV
1Gal′), 98.8 (C-1I), 98.5 (C-1GlcN), 98.2 (C-1GlcN′), 82.9 (C-3II), 78.8
(C-4Gal′), 78.0 (C-3I), 77.7 (C-4Gal), 76.9 (C-4II), 76.4 (C-4I), 74.8
(C-5II), 74.5 (CH2Ph), 74.3 (CH2Ph), 74.1 (C-3Gal’), 73.6 (3 C, 2
CH2Ph and C-3Gal), 73.4 (CH2Ph), 73.2 (CH2Ph), 73.0 (CH2Ph),
72.8 (C-5Gal), 72.6 (C-5Gal’), 72.5 (C-3GlcN), 72.4 (C-2Gal’), 72.2 (C-
3GlcN′), 71.9 (C-2Gal), 71.7 (C-5GlcN), 71.5 (C-5GlcN′), 71.3 (C-4GlcN),
71.2 (C-4GlcN′), 69.7 (C-5I), 69.6 (C-6GlcN), 69.5 (C-6GlcN′), 69.0 (C-
6I), 68.3 (C-6II), 67.7 (C-6Gal), 67.4 (C-6Gal’), 61.2 (C-2GlcN′), 61.00
(C-2GlcN), 59.7 (C-2I), 56.7 (C-2II), 55.3 (OCH3), 51.6 (N-CH2Ph),
51.4 (N-CH2Ph).
3.0 Hz, 1 H, H-4V), 3.92 (dd, J2 IV ) 10.5 Hz, 1 H, H-2IV), 3.91
,3
VI VI II II
(dd, J2
) 10.5 Hz, 1 H, H-2VI), 3.85 (dd, J5
) 5.5 Hz, 1
,3
,6 b
IV IV
IV IV
H, H-6IIb), 3.83 (dd, J5
) 3.5 Hz, J6
) 12.5 Hz, 1 H,
,6
a
a,6
b
H-6IVa), 3.79 (dd, J3 IV ) 9.0 Hz, 1 H, H-3IV), 3.79 (dd, J3
IV
VI VI
,4
,4
II II
) 9.0 Hz, 1 H, H-3VI), 3.77 (dd, J2
) 10.0 Hz, 1 H, H-2II),
III III
,3
3.77 (m, 1 H, H-6IVb), 3.76 (m, 1 H, H-6VIb), 3.74 (dd, J2
)
,3
10.5 Hz, 1 H, H-3III), 3.73 (m, 1 H, H-4II), 3.73 (m, 1 H, H-6Ib),
3.69 (dd, J2 V ) 10.5 Hz, 1 H, H-3V), 3.61 (m, 1 H, H-5II), 3.59
V
,3
(dd, 1 H, H-2III), 3.55 (dd, 1 H, H-2V), 3.54 (dd, J4 IV ) 9.5 Hz,
IV
,5
VI VI
1 H, H-4IV), 3.54 (dd, J4
) 10.0 Hz, 1 H, H-4VI), 3.79-3.67
,5
(m, 6 H, H-5III, H-6IIIa, H-6IIIb, H-5V, H-6Va and H-6Vb), 3.36 (s,
3 H, OCH3), 2.08, 2.06, 2.02 and 2.01 (s, 3 H each, NAc); 13C
NMR (125 MHz, D2O at 30 °C) δ: 175.3, 175.0 and 174.9 (2 C)
(NCOCH3), 105.5 (C-1V), 103.9 (C-1III), 102.1 (C-1II), 99.1 (C-
1VI), 98.9 (C-1I), 98.8 (C-1IV), 79.4 (C-4II), 77.7 (2 C, C-3I and
C-4III), 77.3 (C-4V), 76.3 (C-5III either C-5V), 76.0 (C-5III either
C-5V), 75.5 (C-5II), 73.1 (C-3II), 72.6 (4 C, C-3III, C-3V, C-5IV and
C-5VI), 71.4 (C-3III), 71.1 (2 C, C-3IV and C-3VI), 71.1 (C-2V), 70.6
(C-6I), 70.3 (2 C, C-4IV and C-4VI), 70.1 (C-5I), 69.7 (C-4I), 60.9
(C-6V either C-6III), 60.8 (C-6V either C-6III), 60.7 (3 C, C-6II, C-6IV
and C-6VI), 55.9 (C-2II), 55.6 (OCH3), 54.6 (2 C, C-2IV and C-2VI),
49.2 (C-2I), 22.8, 22.7, 22.5 and 22.5 (NCOCH3). HRMS (ESI-Q-
TOF) calcd for C45H76N4O31+Na 1191.4391; found 1191.4387.
The mixture of the N,O-deacylated compound (68 mg, 0.037
mmol) and 20% Pd(OH)2/C (50 mg) in 80% acetic acid (6 mL)
was stirred at 60 °C under H2 atmosphere overnight. The mixture
was filtered through a syringe filter (Millipore Millex LG, hydro-
philic PTFE 0.2 µm cartridge), and the cartridge was washed with
MeOH and water. The filtrates were concentrated with toluene and
dried in Vacuo. The residue was dissolved in MeOH-water (1:1,
4 mL), neutralized by ion-exchange resin (PS-Trisamine; Argonaut
Tecnologies), and filtered. The filtrate was concentrated in Vacuo,
and the residue was N-acetylated with Ac2O-MeOH (3:7, 5 mL)
at room temperature for 2 h. The residue was concentrated,
neutralized, and re-N-acetylated as described above to give fully
N-acetylated products containing partial O-acetates. The product
was dissolved in MeOH (3 mL), and the solution was adjusted to
pH 9 by addition of a 0.1 M solution of NaOMe in methanol for
3 h, neutralized by Amberlyst (15 DRY), filtered, and concentrated.
The residue was fractionated by size-exclusion chromatography
(Sephadex LH-20; 1:1, MeOH-water) and lyophilized to give 1b
Acknowledgment. S. M. thanks the RIKEN’s matching fund
for PRESTO, President’s Discretionary Fund from RIKEN. We
thank Dr. Teiji Chihara and his staff for elemental analyses,
Dr. Kaori Otsuki and Dr. Masaya Usui at the Research Resource
Center of RIKEN’s Brain Science Center for high-resolution
MS measurement. We thank Ms. Akemi Takahashi for her
technical assistance.
26
1
(29 mg, 67%) as a white powder. [R]D +110 (c 1.0, H2O). H
NMR (500 MHz, D2O at 30 °C) δ: 4.88 (d, J1 VI ) 4.0 Hz, 1 H,
VI
,2
IV
I
H-1VI), 4.87 (d, J1 IV ) 3.5 Hz, 1 H, H-1IV), 4.76 (d, J1 ,2I ) 3.5
,2
Hz, 1 H, H-1I), 4.57 (d, J1 II ) 8.0 Hz, 1 H, H-1II), 4.53 (d, J1
II
III III
,2
,2
V
V
) 7.5 Hz, 1 H, H-1III), 4.52 (d, J1
) 8.0 Hz, 1 H, H-1V), 4.36
,2
(dd, J2 ,3I ) 11.0 Hz, 1 H, H-2I), 4.18 (d, 1 H, J3 ,4I ) 3.5 Hz, 1 H,
I
I
Supporting Information Available: Copies of NMR spectra
for all new compounds. This material is available free of charge
via the Internet at http://pubs.acs.org.
I
I
H-4I), 4.18 (m, 1 H, H-5IV), 4.17 (m, 1 H, H-5VI), 4.08 (dd, J5 ,6 a
I
I
) 3.0 Hz, J6 a,6 b ) 12.5 Hz, 1 H, H-6Ia), 4.05 (m, 1 H, H-5I), 4.04
(dd, 1 H, H-3I), 4.02 (dd, J5 a ) 2.0 Hz, J6
b ) 11.0 Hz, 1 H,
II II
II II
,6
a,6
H-6IIa), 3.99 (d, J3
) 3.5 Hz, 1 H, H-4III), 3.97 (d, J3
)
JO070669P
III III
V V
,4
,4
J. Org. Chem, Vol. 72, No. 16, 2007 6115