Efficiently synthesizing lacto-ganglio-series gangliosides by using a glucosyl ceramide cassette approach: The total synthesis of ganglioside X2

Article abstract of DOI:10.1002/asia.201100928

The first total synthesis of the hybrid ganglioside X2, which consisted of a highly branched octasaccharide and ceramide moieties, was accomplished by using a glucosyl ceramide cassette approach. With a disaccharyl donor, the heptasaccharide could not be constructed by glycosylation of the C4 hydroxy group of galactose at the reducing end of the pentasaccharide. In contrast, through an alternative approach with two branched glycan units, a GM2-core trisaccharide, and a lacto-ganglio tetrasaccharide, the heptasaccharyl donor could be prepared and subsequently joined with a glucosyl ceramide cassette to afford the protected ganglioside, X2. Finally, global deprotection completed the synthesis, thus affording the pure ganglioside X2.

Full text of DOI:10.1002/asia.201100928

DOI: 10.1002/asia.201100928
Efficiently Synthesizing Lacto-Ganglio-Series Gangliosides by Using a
Glucosyl Ceramide Cassette Approach: The Total Synthesis of
Ganglioside X2**
Shinya Nakashima,[a, b] Hiromune Ando,*[a, b] Risa Saito,[a] Hideki Tamai,[a, b]
Hideharu Ishida,[a] and Makoto Kiso*[a, b]
Abstract: The first total synthesis of
the hybrid ganglioside X2, which con-
sisted of a highly branched octasacchar-
ide and ceramide moieties, was accom-
plished by using a glucosyl ceramide
cassette approach. With a disaccharyl
donor, the heptasaccharide could not
be constructed by glycosylation of the
C4 hydroxy group of galactose at the
reducing end of the pentasaccharide. In
contrast, through an alternative ap-
proach with two branched glycan units,
a GM2-core trisaccharide, and a lacto-
ganglio tetrasaccharide, the heptasac-
charyl donor could be prepared and
subsequently joined with a glucosyl ce-
ramide cassette to afford the protected
ganglioside, X2. Finally, global depro-
tection completed the synthesis, thus
affording the pure ganglioside X2.
Keywords: amyotrophic
lateral
sclerosis · gangliosides · oligosac-
charides · sialic acid · total synthesis
Introduction
ganglio-series gangliosides in which the core sequences of
lacto- and ganglio-series gangliosides, namely, Galb-
Amyotrophic lateral sclerosis (ALS) is characterized by the
progressive and selective degeneration of motor neurons in
the brain and spinal cord, and the etiology and pathogenesis
of this debilitating disease are still unknown. However, an
ALS-like disorder was found to be induced by the therapeu-
tic intramuscular administration of a mixture of bovine
brain gangliosides to a patient with a neurological disor-
der.[1] Because an extremely high concentration of anti-GM2
IgM was detected in the patientꢀs serum and because the re-
covery was rapid after plasmapheresis,[1,2] anti-GM2 IgM
was thought to be the main cause of the ALS-like disorder.
The target molecule of this study, ganglioside X2 (2), which
contains a GM2 core, was identified in bovine brain ganglio-
sides by using the patientꢀs IgM together with ganglioside
X1 (1)[3] (Scheme 1). These hybrid gangliosides are lacto-
ACHTUNGTERNN(UNG 1,3)GlcNAcbACHUTNGTRENNUG(1,3)Gal and GalbACHTUNGERTNNG(UN 1,3)GalNAcbACHTNUGTREN(GUNN 1,4)Gal, are
hybridized in their glycan moieties. Their unusual structures
are hypothesized to be immunogenic in humans or to be tar-
gets of autoantibodies in some patients who are misdiag-
nosed with ALS. In this context, the gangliosides should be
useful for identifying such patients, who can be treated with
immunotherapy. However, isolating enough gangliosides of
sufficient quality is difficult from natural sources because
they are structurally diverse and present in the cell mem-
brane in very small amounts. To obtain a pure ganglioside,
we recently synthesized ganglioside X1; furthermore, we
confirmed that serum IgM binds to synthetic ganglioside
X1.[4] Accordingly, our next goal was to chemically synthe-
size ganglioside X2 to provide access to the complete set of
these hybrid gangliosides, which are expected to be useful in
distinguishing treatable patients with an ALS-like disorder
from patients diagnosed with ALS. Herein, we report the
total synthesis of ganglioside X2.
[a] S. Nakashima, Dr. H. Ando, R. Saito, H. Tamai, Dr. H. Ishida,
Dr. M. Kiso
Department of Applied Bioorganic Chemistry
Gifu University
1-1 Yanagido, Gifu-shi, Gifu 501-1193 (Japan)
Fax : (+81)58-293-3452
hando@ gifu-u.ac.jp
Results and Discussion
[b] S. Nakashima, Dr. H. Ando, H. Tamai, Dr. M. Kiso
Institute for Integrated Cell-Material Sciences
WPI-iCeMS
We wanted to establish a synthetic route that provided easy
access to both gangliosides X1 (1) and X2 (2) for their use
in advanced immunological and diagnostic studies. In our
synthesis of ganglioside X1, the final coupling between the
heptasaccharide and the ceramide provided a low yield of
the desired product (26%), which was accompanied by the
hemiacetal (61%) and trichloroacetylaminoglycoside (10%)
by-products from the heptasaccharyl trichloroacetimidate
donor. Because the aminoglycoside and ganglioside X1 had
Kyoto University
Yoshida Ushinomiya-cho, Sakyo-ku
Kyoto 606-8501 (Japan)
[**] Part 156 in the series: Synthetic studies on sialoglycoconjugates. For
part 155, see: Synthesis of the disialic acid-embedded glycan part of
ganglioside HPG-1, Ref. [16].
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/asia.201100928.
Chem. Asian J. 2012, 7, 1041 – 1051
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1041

FULL PAPERS
tions on the inner disaccharide
unit (GlcNAcb(1,3)Gal). The
AHCTUNGTRENNUNG
2,2,2-trichloroethoxycarbonyl
(Troc) group was chosen for
protection of the C3 hydroxy
group of the glucosaminyl
donor, and the di-tert-butylsilyl
(DTBS) group was chosen for
the simultaneous protection of
the C4 and C6 hydroxy groups
of the galactosyl acceptor,
Scheme 1. Structures of gangliosides X1 (1) and X2 (2) found in bovine brain.
thereby providing glucosaminyl
unit 7[4] and galactosaminyl unit
8,[7] respectively (Scheme 3).
similar mobilities on silica gel, chromatographic separation
was challenging and some fractions of eluent that contained
the desired compound were inevitably lost. In addition, with
the previous synthetic route developed for ganglioside X1,
common synthetic intermediates could not be fully applied
to the preparation of both gangliosides X1 and X2. Taking
into account the major drawbacks of the previous route, we
envisaged a new approach to ganglioside X2 (Scheme 2). To
avoid the loss of the valuable oligosaccharyl donor during
the coupling of the self-aggregating, bulky, and unreactive
ceramide, we recently developed a glucosyl ceramide (Glc-
Cer) cassette approach.[5] This approach was used to con-
struct the very complicated framework of the target com-
pound, with the aim of improving the coupling yields and ef-
ficiency of the chromatographic purification. Thus, retrosyn-
thetic analysis of the target molecule (2) first provided hep-
tasaccharide 3 and Glc-Cer cassette 4. Heptasaccharide 3
First, inner disaccharide unit 9 was prepared in good yield
by the straightforward glycosidation of compound 7 with
compound 8, followed by conversion into the corresponding
disaccharyl acceptor (10) by the selective deprotection of
the Troc groups and N-acetylation. Next, the glycosylation
of compound 10 (1.0 equiv) with GM2-core donor 11[6]
(1.0 equiv; TMSOTf, CH2Cl2, 08C) produced pentasacchar-
ide 12 in 77% yield. For conversion into acceptor 13, the
DTBS moiety in compound 12 was selectively removed by
treatment with tributylamine hydrofluoride (TBAHF)[8] to
deprotect the C4 and C6 hydroxy groups, and the C6 hy-
droxy group was selectively protected with an acetyl group
under mild conditions. Next, pentasaccharide acceptor 13
was subjected to glycosylation with glycosyl donor 14.[9]
However, the glycosylation reaction, promoted by N-iodo-
succinimide (NIS) and trifluoromethanesulfonic acid
(TfOH),[10] could not produce the desired compound (16).
By using trichloroacetimidate donor 15, the heptasaccharide
was generated in very poor yield (ca. 10–20%). To our dis-
appointment, we were unable to improve the glycosylation
yield.
was disconnected at the bACTHUNRGTNE(NUG 1,4)-linkage between galactosa-
mine and galactose to give disaccharyl donor 6 and penta-
saccharyl acceptor 5, which could also be used for the syn-
thesis of ganglioside X1. Pentasaccharide 5 should be acces-
sible from the known GM2-core donor[6] plus a suitably pro-
tected disaccharide acceptor.
Because of the poor yield from the glycosylation of the
pentasaccharyl acceptor, an alternative route was devised to
synthesize ganglioside X2 (Scheme 4). Although the
common synthetic route to gangliosides X1 and X2 became
shorter than that in the first at-
For the pentasaccharyl acceptor (5), we chose a set of or-
thogonal protecting groups for the latent glycosylation posi-
tempt, the heptasaccharide
moiety (3) in the target mole-
cule was disassembled at the b-
glycosidic linkage between Gal
and GlcN, thereby providing
the GM2-core unit (11) and the
tetrasaccharide
(hybrid-core)
unit (17), which further frag-
mented into disaccharide units
6 and 18.
Hybrid-core unit 17 was suit-
ably protected to give com-
pound 24 in high overall yield
(Scheme 5). First, disaccharyl
acceptor 20 was synthesized
from compound 9 with the pro-
tecting groups being manipulat-
Scheme 2. Retrosynthetic analysis of target compound 2. P=protecting group, LG=leaving group.
1042
www.chemasianj.org
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 2012, 7, 1041 – 1051

A Glucosyl Ceramide Cassette Approach to Gangliosides
comparison of the results from
the glycosylation of heptasac-
charide 13 and disaccharide 20
with compound 14 suggested
that the reactivity of the C4 hy-
droxy group in compound 13
was attenuated by the steric
bulk of the GlcN residue.
In line with our expectations,
glycosyl acceptor 24 was a good
coupling partner for GM2-core
donor 11, and generated highly
branched heptasaccharide 25 in
81% yield (Scheme 6). Then,
compound 25 was converted
into the corresponding glycosyl
imidate donor. To replace the
acid-labile benzylidene acetal
moiety with acetyl groups, com-
pound 25 was treated with 90%
AcOH (aq.) at 608C and then
with Ac2O and DMAP in pyri-
dine to afford compound 26. Fi-
nally, the p-methoxyphenyl
group at the anomeric position
of compound 26 was selectively
cleaved by treatment with CAN
and water,[12] and the resulting
hemiacetal was treated with
CCl3CN in the presence of
DBU[13] to furnish heptasac-
charyl imidate donor 27 in good
yield.
In our previous study on the
synthesis of GQ1b,[5a] we found
that Glc-Cer cassette 34 could
accept highly branched oligo-
saccharyl donors to provide
ganglioside frameworks in high
yields. However, the moderate
yield (48%) from the coupling
of the Glc donor (1.5 equiv)
Scheme 3. First approach to the heptasaccharide fragment: a) (i) Zn, AcOH/MeCN, RT; (ii) Ac2O, CH2Cl2/
MeOH 2:1, RT, 93% (2 steps); b) (i) TBAHF, RT; (ii) Ac2O, pyridine, THF, ꢀ208C to RT, 75% (2 steps);
c) (i) NBS, H2O/acetone 1:20, RT; (ii) CCl3CN, DBU, CH2Cl2, RT, 91% (2 steps); d) compound 14, NIS, TfOH,
CH2Cl2, 4 ꢂ M.S., ꢀ208C; e) compound 15, TMSOTf, CH2Cl2, 4 ꢂ M.S. (AW-300), 08C to RT. Troc=2,2,2-tri-
chloroethoxycarbonyl, MP=p-methoxyphenyl, Bz=benzoyl, NIS=N-iodosuccinimide, TfOH=trifluorome-
thanesulfonic acid, M.S.=molecular sieves, TMSOTf=trimethylsilyl trifluoromethanesulfonate, TBAHF=tri-
and
the
Cer
acceptor
(1.0 equiv) limited the scope of
its applications in ganglioside
synthesis. Herein, we improved
the glycosylation yield by intro-
ducing a tert-butyldimethylsilyl
n-butylamine hydrofluoride, NBS=N-bromosuccinimide, DBU=1,8-diazabicyclo
di-tert-butylsilylene.
ACHTUNGTNER[NUNG 5.4.0]undec-7-ene, DTBS=
ed in a similar manner to the conversion of compound 12
into compound 13. Next, the NIS/TfOH-mediated coupling
of acceptor 20 with Gal-GalN donor 14 was performed to
yield tetrasaccharide 23 in 82% yield. By using GalN donor
21,[11] compound 20 was converted into the hybrid-core
structure of ganglioside X1 in high yield. In the final step,
deprotection of the Troc groups and subsequent acetylation
of the resulting amine group in compound 23 produced
hybrid-core acceptor 24 in 93% yield over two steps. A
(TBS) group at the C4 hydroxy group of the Glc donor.
Phenylthioglycoside donor 30 and imidate donor 31, which
were derived from compound 28[14] through a sequence of
conventional reactions, provided high yields (77% and
78%) of Glc-Cer 33 from the glycosidation reaction with ce-
ramide acceptor 32[15] (Scheme 7). Next, the TBS group was
cleaved to afford Glc-Cer cassette 34 in 95% yield.
In the final stage of this synthesis, to build the glycolipid
framework of ganglioside X2, the coupling reaction between
Chem. Asian J. 2012, 7, 1041 – 1051
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
1043

H. Ando, M. Kiso et al.
FULL PAPERS
heptasaccharyl donor (27) and
the Glc-Cer cassette (34) was
promoted by a catalytic amount
of TMSOTf in CHCl3 at 08C,
thus providing compound 35 in
83% yield together with the tri-
chloroactylaminoglycoside ana-
logue of compound 27 (about
7%; Scheme 8). Chromato-
graphic separation of the reac-
tion mixture was straightfor-
ward owing to the large differ-
ence in mobility on silica gel
between the heptasaccharyl by-
product and the desired octa-
Scheme 4. Revised retrosynthetic analysis of the heptasaccharide part.
saccharyl ceramide 35. The Glc-
Cer cassette method afforded a
high yield, and, more importantly, allowed for the efficient
production of pure ganglioside with a high degree of repro-
ducibility. Finally, p-methoxybenzyl groups were removed
under acidic conditions (TFA, CH2Cl2, 08C, 98%), followed
by deacylation under Zemplꢃn conditions and subsequent
saponification of methyl ester in sialic acid (97% yield over
two steps). This global deprotection successfully provided
30.6 mg of pure ganglioside X2 (2), which is a sufficient
amount for use in immunological and diagnostic studies.
Conclusions
Although our first attempted route was unsuccessful, we
successfully completed the first total synthesis of the hybrid
ganglioside X2 by using a modified convergent route. By ap-
plying the Glc-Cer cassette approach, the assembly of the
glycolipid framework, which is critical in ganglioside synthe-
Scheme 5. Synthesis of inner-hyprid-core acceptor 24: a) Ac2O, pyridine,
THF, ꢀ208C to RT, 83%; b) (i) Zn, AcOH, THF, RT; (ii) Ac2O, CH2Cl2/
MeOH 2:1, RT, 93% (2 steps). Gal=2,3,4,6-tetra-O-acetyl-b-d-galacto-
pyranosyl.
Scheme 7. Synthesis of the Glc-Cer acceptor 34. a) DBTO, toluene,
reflux, then MBnCl, TBAB, 83% (crystal); b) (i) NBS, H2O/acetone 1:20,
RT; (ii) CCl3CN, DBU, CH2Cl2, RT, 83% (2 steps); c) compound 30
(1.0 equiv), DMTST, CH2Cl2, 4 ꢂ M.S., RT, 77%; d) compound 31
(1.0 equiv), TMSOTf, CH2Cl2, 4 ꢂ M.S. (AW-300), RT, 78%; e) TBAF,
AcOH, THF, RT, 95%. MBn=p-methoxybenzyl, DBTO=dibutyltin(IV)
oxide, TBAB=n-tetrabutylammonium bromide, TBSOTf=tert-butyldi-
methylsilyl trifluoromethanesulfonate, DMTST=dimethyl(methylthio)-
sulfonium trifluoromethanesulfonate, TBAF=n-tetrabutylammonium
fluoride.
Scheme 6. Assembly of heptasaccharide and conversion into the glycosyl
donor: a) (i) 90% AcOH (aq.), 608C; (ii) Ac2O, DMAP, pyridine, RT,
96% (2 steps); b) (i) CAN, MeCN/toluene/H2O 6:5:3, 08C; (ii) CCl3CN,
DBU, CH2Cl2, RT, 84% (2 steps). Bzld=benzylidene, DMAP=4-dime-
thylaminopyridine, CAN=ceric(IV) ammonium nitrate.
1044
www.chemasianj.org
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 2012, 7, 1041 – 1051

A Glucosyl Ceramide Cassette Approach to Gangliosides
pension was stirred for 30 min at
ꢀ208C, whereupon NIS (91 mg,
407 mmol)
and
TfOH
(3.6 mL,
40.7 mmol) were added. Stirring was
continued for 30 min at ꢀ208C (com-
pletion of the reaction was confirmed
by TLC analysis; EtOAc/n-hexane,
2:5). The reaction mixture was
quenched with saturated aqueous
NaHCO3, filtered through celite, and
the molecular sieves were washed with
CHCl3. The combined filtrate and
washings were extracted with CHCl3,
and the organic layer was washed with
saturated aqueous Na2S2O3, dried
(Na2SO4), and concentrated under
vacuum. The residue was purified by
column chromatography on silica gel
(EtOAc/toluene, 1:4!1:3) and column
chromatography on Sephadex LH-20
(CHCl3/MeOH, 1:1) to give compound
9 (157 mg, 77%). [a]D =+3.5 (c=1.0,
CHCl3); 1H NMR (600 MHz, CDCl3):
d=8.08–7.32 (m, 10H; 2ꢄPh), 6.89–
Scheme 8. Final coupling and global deprotection to afford ganglioside X2 (2): a) TFA, CH2Cl2, 08C, 98%.
TFA=trifluoroacetic acid.
6.72 (m, 4H; Ar), 5.80 (dd, JACHTUNGTRENNUNG
7.6 Hz,
JACHTUNGTRENNUNG
5.63 (t, J
N
ACHTUNGTRENNUNG
3c), 5.51 (s, 1H; PhCH), 5.30 (d, J-
(1,2)=8.2 Hz, 1H; H-1c), 5.21 (d, J(2,NH)=6.1 Hz, 1H; NH), 4.92 (d,
1H; H-1b), 4.69 (d, J(3,4)=2.8 Hz, 1H; H-4b), 4.67–4.65 (m, 2H; CH2),
4.46 (d, J(gem)=11.7 Hz, 1H; CH2), 4.34 (dd, J(5,6)=4.8 Hz, J(gem)=
10.3 Hz, 1H; H-6c), 4.31–4.28 (m, 2H; H-6b, H-6’b), 3.82 (dd, 1H; H-
3b), 3.75–3.69 (m, 2H; H-4c, H-6’c), 3.73 (s, 3H; OMe), 3.61 (m, 1H; H-
5c), 3.52 (s, 1H; H-5b), 3.36–3.34 (m, 2H; CH2, H-2c), 1.15 and 1.09 ppm
(2 s, 18H; 2ꢄtBu); 13C NMR (150 MHz, CDCl3): d=165.2, 155.6, 153.4,
151.4, 136.6, 133.3, 129.8, 129.2, 128.7, 128.2, 126.1, 119.6, 114.3, 101.6,
101.4, 100.8, 95.2, 94.2, 81.3, 78.8, 74.4, 73.3, 72.3, 71.4, 70.3, 68.6, 67.0,
65.7, 57.5, 55.5, 27.5, 27.5, 23.5, 20.7 ppm; HRMS (ESI): m/z calcd for
C47H55Cl6NO16Si+Na+: 1150.1313 [M+Na]+; found: 1150.1313.
G
ACHTUNGTRENNUNG
sis, was successfully performed. The quantity of X2 prepared
from this first synthesis (30.6 mg) accentuated the efficacy
and practicality of this synthetic route. Based on the synthe-
sized compounds X1 and X2, we are currently working to
develop a diagnostic method for distinguishing between pa-
tients with ALS and treatable patients with an ALS-like dis-
order.
AHCTUNGTRENNUNG
G
U
ACHTUNGTRENNUNG
Experimental Section
4-Methoxyphenyl 2-acetamido-4,6-O-benzylidene-2-deoxy-b-d-
glucopyranosyl-(1!3)-2-O-benzoyl-4,6-O-di-tert-butylsilylene-b-d-
galactopyranoside (10)
General Procedures
1H and 13C NMR spectra were recorded on JEOL JNM-ECA500 and 600
spectrometers. H NMR chemical shifts are expressed in ppm (d) relative
Zinc powder (1.5 g) was added to a solution of compound 9 (296 mg,
262 mmol) in MeCN (8.0 mL) and AcOH (2.0 mL) and the mixture was
stirred for 20 min at room temperature (completion of the reaction was
confirmed by TLC analysis; CHCl3/MeOH, 20:1). The reaction mixture
was filtered through celite and the zinc powder was washed with EtOAc.
The combined filtrate and washings were extracted with EtOAc, and the
organic layer was washed with saturated aqueous Na2CO3 and brine,
dried (Na2SO4), concentrated under vacuum, and exposed to high
vacuum for 14 h. The residue was treated with a solution of Ac2O (74 mL,
786 mmol) in CH2Cl2/MeOH (1.7 mL:0.9 mL) for 30 min at room temper-
ature (completion of the reaction was confirmed by TLC analysis;
CHCl3/MeOH, 20:1). The mixture was concentrated under vacuum and
the residue was purified by column chromatography on silica gel (CHCl3/
acetone, 80:1!50:1) to give compound 10 (201 mg, 93%). [a]D =ꢀ5.0
1
to Me4Si as an internal standard. 13C NMR chemical shifts are expressed
in ppm (d) relative to the solvent as a standard. High-resolution mass
spectrometry (HRMS) was performed on a Bruker Daltonics micrOTOF
(ESI-TOF) mass spectrometer. Specific rotations were measured with a
Horiba SEPA-300 high-sensitivity polarimeter. Melting points were deter-
mined by using an AS ONE ATM-01. Molecular sieves were purchased
from Wako Chemicals Inc. and dried at 3008C for 2 h in a muffle furnace
prior to use. Reactions were carried out under an argon atmosphere
unless otherwise specified. Solvents as reaction media were dried over
molecular sieves and used without further purification. TLC analysis was
performed on Merck TLC plates (silica gel 60F254 on glass). Compounds
were visualized either by exposure to UV light (254 nm), or by spraying
with a 10% H2SO4 solution in EtOH or ninhydrin, followed by heating.
Flash column chromatography on silica gel (Fuji Silysia Co., 80 mesh,
300 mesh and Mitsubishi Chemical Medience Co., Iatrobeads 6RS-8060)
or Sephadex (Pharmacia LH-20) was performed with the solvent systems
(v/v) specified. Evaporation and concentration were conducted in vacuo.
1
(c=1.3, CHCl3); H NMR (600 MHz, CDCl3): d=8.07–7.31 (m, 10H; 2ꢄ
Ph), 6.92–6.74 (m, 4H; Ar), 5.90 (br s, 1H; NH), 5.79 (dd, J
(2,3)=10.0 Hz, 1H; H-2b), 5.55 (s, 1H; PhCH), 4.98 (d, 1H; H-1b), 4.85
(d, J(1,2)=7.6 Hz, 1H; H-1c), 4.77 (s, 1H; OH), 4.65 (d, J(3,4)=2.7 Hz,
1H; H-4b), 4.33–4.27 (m, 3H; H-6b, H-6’b, H-6c), 4.11 (t, J(2,3)=J-
(3,4)=9.0 Hz, 1H; H-3c), 3.84 (dd, 1H; H-3b), 3.74 (s, 3H; OMe), 3.73
(t, J(5,6’)=J(gem)=10.0 Hz, 1H; H-6’c), 3.53 (s, 1H; H-5b), 3.53 (t, J-
(4,5)=9.0 Hz, 1H; H-4c), 3.44 (ddd, J(5,6)=4.8 Hz, 1H; H-5c), 3.30
(ddd, J
ACHTUNGTREN(NUNG 1,2)=7.6 Hz,
JACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
4-Methoxyphenyl-4,6-O-benzylidene-2-deoxy-2-(2,2,2-
trichloroethoxycarbamoyl)-3-O-(2,2,2-trichloroethoxycarbonyl)-b-d-
glucopyranosyl-(1!3)-2-O-benzoyl-4,6-O-di-tert-butylsilylene-b-d-
galactopyranoside (9)
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
AHCTUNGTREG(NNNU 2,NH)=4.1 Hz, 1H; H-2c), 1.70 (s, 3H; Ac), 1.14 and 1.09 ppm
(2 s, 18H; 2ꢄtBu); 13C NMR (150 MHz, CDCl3): d=172.6, 166.0, 155.7,
151.3, 136.9, 129.7, 129.3, 129.2, 128.8, 128.2, 126.3, 119.6, 114.4, 101.9,
101.4, 101.3, 81.5, 80.1, 72.5, 71.5, 71.3, 70.3, 68.6, 66.9, 66.3, 60.2, 55.6,
Molecular sieves (4 ꢂ, 500 mg) were added to a solution of compounds 7
(192 mg, 271 mmol) and 8 (96 mg, 181 mmol) in CH2Cl2 (4.5 mL). The sus-
Chem. Asian J. 2012, 7, 1041 – 1051
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
1045

H. Ando, M. Kiso et al.
FULL PAPERS
27.5, 27.4, 23.4, 22.8, 20.7 ppm; HRMS (ESI): m/z calcd for
C43H55NO13Si+Na+: 844.3335 [M+Na]+; found: 844.3334.
and pyridine (46.0 mL, 560 mmol) were added to the mixture and stirring
was continued for 84 h at room temperature (completion of the reaction
was confirmed by TLC analysis; CHCl3/MeOH, 15:1; developed twice).
Then the reaction mixture was quenched with MeOH and concentrated
under vacuum. The residue was purified by column chromatography on
silica gel (CHCl3/MeOH, 40:1!30:1, then CHCl3/acetone, 3:2!1:2) to
4-Methoxyphenyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-
d-glycero-a-d-galacto-2-nonulopyranosylonate)-(2!3)-{2-acetamido-
3,4,6-tri-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-
b-d-galactopyranosyl-(1!3)-2-acetamido-4,6-O-benzylidene-2-deoxy-b-d-
glucopyranosyl-(1!3)-2-O-benzoyl-4,6-O-di-tert-butylsilylene-b-d-
galactopyranoside (12)
1
give compound 13 (43 mg, 75%). [a]D =ꢀ12.1 (c=0.7, CHCl3); H NMR
(600 MHz, CDCl3): d=8.01–7.09 (m, 20H; 4ꢄPh), 6.87–6.70 (m, 4H;
Ar), 6.07 (d, J
(2,3)=9.7 Hz, 1H; H-2b), 5.57 (dd, J
H-3h), 5.49 (br s, 1H; NHc), 5.48 (s, 1H; PhCH), 5.37 (m, 1H; H-8g),
5.29 (d, 1H; H-4h), 5.28–5.25 (m, 2H; H-1c, H-2f), 5.19 (dd, J(6,7)=
2.1 Hz, J(7,8)=10.3 Hz, 1H; H-7g), 5.10 (d, J(5,NH)=8.3 Hz, 1H; NHg),
5.05 (d, J(1,2)=9.0 Hz, 1H; H-1h), 4.89 (ddd, J(3eq,4)=4.2 Hz, J(3ax,4)=
(4,5)=10.4 Hz, 1H; H-4g), 4.86 (d, J(1,2)=8.3 Hz, 1H; H-1f), 4.85 (d,
1H; H-1b), 4.64 (dd, J(5,6)=6.9 Hz, J(gem)=11.0 Hz, 1H; H-6c), 4.48 (t,
(2,3)=J(3,4)=9.3 Hz, 1H; H-3c), 4.44 (dd, J(5,6)=7.6 Hz, J(gem)=
11.7 Hz, 1H; H-6f), 4.40 (dd, J(5,6’)=4.8 Hz, 1H; H-6’f), 4.24–4.21 (m,
2H; H-6b, H-3f), 4.08–4.03 (m, 3H; H-4b, H-6’c, H-9g), 3.99 (dd, J-
(8,9’)=5.5 Hz, (gem)=12.4 Hz, 1H; H-9g), 3.95 (t, (5,6)=J(5,6’)=
A
ACHTUNGTREN(NGNU 1,2)=8.3 Hz, J-
A
R
ACHTUNGTRENNUNG
AW-300 molecular sieves (4 ꢂ, 300 mg) were added to a solution of com-
pounds 11 (104 mg, 77.9 mmol) and 10 (64 mg, 77.9 mmol) in CH2Cl2
(1.6 mL). The suspension was stirred for 30 min at 08C, whereupon
TMSOTf (0.7 mL, 3.90 mmol) was added. Stirring was continued for
30 min at 08C (completion of the reaction was confirmed by TLC analy-
sis; CHCl3/acetone, 1:1). The reaction mixture was quenched with satu-
rated aqueous NaHCO3, filtered through celite, and the molecular sieves
were washed with CHCl3. The combined filtrate and washings were ex-
tracted with CHCl3, and the organic layer was washed with saturated
aqueous NaHCO3, dried (Na2SO4), and concentrated under vacuum. The
residue was purified by column chromatography on silica gel (CHCl3/ace-
tone, 5:2!2:1) and column chromatography on Sephadex LH-20
(CHCl3/MeOH, 1:1) to give compound 12 (120 mg, 77%). [a]D =+10.5
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
R
ACHTUNGTRENNUNG
J
N
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
J
G
E
N
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
J
E
J
N
ACHTUNGTRENNUNG
6.5 Hz, 1H; H-5h), 3.91–3.83 (m, 4H; H-3b, H-5g, H-2h, H-6h), 3.81 (dd,
1H; H-5f), 3.79–3.74 (m, 3H; H-4f, H-6g, H-6h), 3.76 and 3.72 (2 s, 6H;
2ꢄOMe), 3.71–3.68 (m, 2H; H-6’b, H-4c), 3.53–3.49 (m, 2H; H-5b, H-
1
(c=1.0, CHCl3); H NMR (600 MHz, CDCl3): d=7.99–7.07 (m, 20H; 4ꢄ
5c), 3.12 (ddd, J
ACHUTGTNRNEUG(N 1,2)=JACHTUGNTREN(NNGU 2,NH)=8.3 Hz, 1H; H-2c), 2.86 (s, 1H; OH),
Ph), 6.87–6.70 (m, 4H; Ar), 6.03 (d, J
(dd, J(1,2)=8.3 Hz, J(2,3)=9.6 Hz, 1H; H-2b), 5.61 (dd, J
(3,4)=3.5 Hz, 1H; H-3h), 5.50 (s, 1H; PhCH), 5.43 (d, J
6.8 Hz, 1H; NHc), 5.36 (m, 1H; H-8g), 5.32 (d, J(1,2)=7.5 Hz, 1H; H-
1c), 5.31–5.28 (m, 2H; H-2f, H-4h), 5.21 (dd, J(6,7)=2.1 Hz, J(7,8)=
10.3 Hz, 1H; H-7g), 5.07 (d, J(1,2)=8.3 Hz, 1H; H-1h), 5.05 (d, J(1,2)=
9.6 Hz, 1H; NHg), 4.90–4.86 (m, 2H; H-1b, H-4g), 4.84 (d, J(1,2)=
8.3 Hz, 1H; H-1f), 4.70 (t, J(2,3)=J(3,4)=9.3 Hz, 1H; H-3c), 4.66 (d, J-
(3,4)=3.4 Hz, 1H; H-4b), 4.64 (dd, (5,6)=8.2 Hz, (gem)=11.0 Hz,
1H; H-6f), 4.29–4.20 (m, 4H; H-6b, H-6’b, H-6c, H-3f), 4.07–3.99 (m,
3H; H-6’f, H-9g, H-9g), 3.92 (t, J(5,6)=J(5,6’)=6.9 Hz, 1H; H-5h), 3.89–
3.75 (m, 6H; H-4f, H-5g, H-6g, H-2h, H-6h, H-6h), 3.74 and 3.72 (2 s,
6H; 2ꢄOMe), 3.70–3.68 (m, 3H; H-3b, H-4c, H-6’c), 3.55 (ddd, J(4,5)=
(5,6’)=4.8 Hz, 1H; H-5c), 3.47 (s, 1H; H-5b), 3.43 (dd,
(5,6)=4.2 Hz, 1H; H-5f), 2.99 (ddd, 1H; H-2c), 2.39 (dd, J(3eq,4)=
(gem)=13.1 Hz, 1H; H-3geq), 2.14, 2.10, 2.01, 2.00, 1.99, and 1.92
ACHTUNGTRENNUNG
2.37 (dd, J(gem)=13.0 Hz, 1H; H-3geq), 2.15, 2.11, 2.09, 2.00, 2.00, 1.95
AHCTUNGTRENNUNG
A
R
ACHTUNGTRENNUNG
and 1.92 (7 s, 21H; 7ꢄAc), 1.84–1.73 (m, 10H; H-3gax, 3ꢄAc), 1.63 ppm
(s, 3H; Ac); 13C NMR (150 MHz, CDCl3): d=171.3, 170.9, 170.7, 170.6,
170.6, 170.4, 170.4, 170.3, 170.1, 169.8, 169.7, 168.1, 165.4, 165.0, 164.6,
155.5, 151.3, 136.9, 133.3, 133.3, 133.2, 129.9, 129.7, 129.6, 129.4, 128.8,
128.5, 128.4, 128.1, 126.1, 118.9, 114.3, 101.4, 101.0, 100.4, 100.2, 100.0,
98.1, 80.6, 80.2, 76.3, 74.8, 73.7, 72.1, 71.9, 71.7, 70.9, 70.7, 70.0, 69.8, 68.8,
68.6, 68.2, 67.1, 66.9, 66.4, 66.0, 63.1, 63.0, 62.2, 61.4, 57.8, 55.6, 53.0, 52.0,
49.0, 36.2, 23.4, 23.1, 21.8, 21.2, 20.8, 20.7, 20.7, 20.6, 20.4, 20.3 ppm;
HRMS (ESI): m/z calcd for C91H105N3O41+Na+: 1918.6116 [M+Na]+;
found: 1918.6116.
J
N
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
J
A
JACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
2,3,4,6-Tetra-O-acetyl-b-d-galactopyranosyl-(1!3)-4,6-di-O-acetyl-2-
deoxy-2-(2,2,2-trichloroethoxycarbamoyl)-a-d-galactopyranosyl
trichloroacetimidate (15)
J
J
CAHTUNGTRENNUNG(5,6)=9.6 Hz, JACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
4.1 Hz, JACHTUNGTRENNUNG
N-Bromosuccinimide (125 mg, 697 mmol) was added to a solution of com-
pound 14 (300 mg, 348 mmol) in acetone/H2O (3.3 mL:0.2 mL). The mix-
ture was stirred for 15 min at room temperature (completion of the reac-
tion was confirmed by TLC analysis; EtOAc/n-hexane, 5:2), then the re-
action mixture was extracted with CHCl3 and the organic layer was
washed with saturated aqueous NaHCO3, dried (Na2SO4), and concen-
trated under vacuum. The residue was purified by column chromatogra-
phy on silica gel (EtOAc/n-hexane, 1:1!3:2) to give the 1-OH deriva-
tives. The derivatives were treated with a solution of trichloroacetonitrile
(700 mL, 6.97 mmol) and DBU (10.0 mL, 69.7 mmol) in CH2Cl2 (3.5 mL)
for 30 min at room temperature (completion of the reaction was con-
firmed by TLC analysis; CHCl3/MeOH, 25:1). The mixture was concen-
trated under vacuum and the residue was purified by column chromatog-
raphy on silica gel (EtOAc/n-hexane, 1:2!2:3) to give compound 15
(289 mg, 91%). [a]D =+75.0 (c=0.6, CHCl3); 1H NMR (600 MHz,
(6 s, 18H; 6ꢄAc), 1.86–1.73 (m, 10H; H-3gax, 3ꢄAc), 1.62 (s, 3H; Ac),
1.13 and 1.08 ppm (2 s, 18H; 2ꢄtBu); 13C NMR (150 MHz, CDCl3): d=
171.2, 170.6, 170.6, 170.5, 170.4, 170.3, 170.3, 170.1, 169.6, 169.5, 168.1,
165.3, 165.1, 164.5, 155.5, 151.4, 137.1, 133.3, 133.2, 133.2, 129.9, 129.7,
129.6, 129.4, 128.7, 128.4, 128.4, 128.1, 126.1, 119.6, 114.2, 101.6, 101.3,
100.4, 100.3, 100.1, 98.0, 81.1, 81.0, 75.9, 74.5, 73.7, 72.3, 71.9, 71.4, 71.4,
70.7, 70.2, 69.9, 69.7, 69.0, 68.8, 67.1, 67.0, 66.9, 66.2, 65.5, 62.7, 62.0, 61.4,
58.6, 55.5, 52.9, 52.2, 49.0, 36.2, 27.5, 27.4, 23.5, 23.4, 23.1, 21.4, 21.2, 20.8,
20.7, 20.6, 20.5, 20.2 ppm; HRMS (ESI): m/z calcd for
C97H119N3O40Si+Na+: 2016.7031 [M+Na]+; found: 2016.7030.
4-Methoxyphenyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-
d-glycero-a-d-galacto-2-nonulopyranosylonate)-(2!3)-{2-acetamido-
3,4,6-tri-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-
b-d-galactopyranosyl-(1!3)-2-acetamido-4,6-O-benzylidene-2-deoxy-b-d-
glucopyranosyl-(1!3)-6-O-acetyl-2-O-benzoyl-b-d-galactopyranoside
(13)
CDCl3): d=8.75 (s, 1H; C=NH), 6.57 (d, J
(d, J(3,4)=2.8 Hz, 1H; H-4d), 5.42 (d, J(2,NH)=7.6 Hz, 1H; NH), 5.39
(d, J(3,4)=3.1 Hz, 1H; H-4e), 5.25 (dd, J(1,2)=8.2 Hz, J(2,3)=10.3 Hz,
1H; H-2e), 4.99 (dd, 1H; H-3e), 4.84 (d, J(gem)=12.1 Hz, 1H; CH2),
4.76 (d, 1H; H-1e), 4.62 (d, 1H; CH2), 4.39 (ddd, J(2,3)=10.3 Hz, 1H;
H-2d), 4.31 (t, J(5,6)=J(5,6’)=6.6 Hz, 1H; H-5e), 4.22–4.16 (m, 4H; H-
ACHTUNGTNER(NUNG 1,2)=3.5 Hz, 1H; H-1d), 5.44
A
ACHTUNGTRENNUNG
A
R
ACHTUNGTRENNUNG
Compound 12 (61 mg, 30.6 mmol) was treated with a solution of tributyla-
mine hydrofluoride (1.0m in THF; 1.0 mL, 1.00 mmol) for 1 h at room
temperature (completion of the reaction was confirmed by TLC analysis;
CHCl3/MeOH, 12:1). The reaction mixture was extracted with CHCl3,
and the organic layer was washed with H2O and saturated aqueous
NaHCO3, dried (Na2SO4), and concentrated under vacuum. The residue
was purified by column chromatography on silica gel (CHCl3/MeOH,
30:1!25:1) and column chromatography on Sephadex LH-20 (CHCl3/
MeOH, 1:1) to give the diol derivative. The derivative was treated with a
solution of Ac2O (2.7 mL, 28.0 mmol) and pyridine (11.5 mL, 140 mmol) in
THF (930 mL). The mixture was stirred for 1 h 15 min at ꢀ208C, for 2.5 h
at 08C, and for 2.5 h at room temperature (monitored by TLC analysis;
CHCl3/MeOH, 15:1; developed twice). Next, Ac2O (24.3 mL, 252 mmol)
AHCTUNGTRENNUNG
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
3d, H-6d, H-6’d, H-6e), 4.14–3.97 (m, 2H; H-5d, H-6’e), 2.19, 2.14, 2.10,
2.04, 2.04, and 1.98 ppm (6 s, 18H; 6ꢄAc); 13C NMR (150 MHz, CDCl3):
d=170.4, 170.2, 170.1, 170.0, 169.9, 169.6, 160.3, 154.1, 99.7, 95.3, 91.0,
74.6, 71.3, 70.9, 69.8, 68.0, 67.5, 66.4, 61.7, 60.4, 50.5, 20.8, 20.7, 20.7, 20.6,
20.5 ppm; HRMS (ESI): m/z calcd for C29H36Cl6N2O18+Na+: 932.9986
[M+Na]+; found: 932.9986.
1046
www.chemasianj.org
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 2012, 7, 1041 – 1051

A Glucosyl Ceramide Cassette Approach to Gangliosides
4-Methoxyphenyl 4,6-O-benzylidene-2-deoxy-2-(2,2,2-
TLC analysis; EtOAc/n-hexane, 3:2). The reaction mixture was quenched
with saturated aqueous NaHCO3, filtered through celite and the molecu-
lar sieves were washed with CHCl3. The combined filtrate and washings
were extracted with CHCl3, and the organic layer was washed with satu-
rated aqueous Na2S2O3, dried (Na2SO4), and concentrated under vacuum.
The residue was purified by column chromatography on silica gel
(EtOAc/n-hexane, 2:3, then CHCl3/acetone, 20:1!15:1) and column
chromatography on Sephadex LH-20 (CHCl3/MeOH, 1:1) to give com-
pound 22 (59 mg, 91%). [a]D =ꢀ10.0 (c=0.5, CHCl3); 1H NMR
(600 MHz, CDCl3): d=8.07–7.35 (m, 10H; 2ꢄPh), 6.89–6.73 (m, 4H;
trichloroethoxycarbamoyl)-3-O-(2,2,2-trichloroethoxycarbonyl)-b-d-
glucopyranosyl-(1!3)-2-O-benzoyl-b-d-galactopyranoside (19)
Compound 9 (257 mg, 227 mmol) was treated with a solution of tributyla-
mine hydrofluoride (1.0m in THF; 2.3 mL, 2.30 mmol) for 1 h at room
temperature (completion of the reaction was confirmed by TLC analysis;
CHCl3/MeOH, 20:1). The reaction mixture was extracted with CHCl3,
and the organic layer was washed with 2m aqueous HCl and saturated
aqueous NaHCO3, dried (Na2SO4), and concentrated under vacuum. The
residue was recrystallized from CHCl3/n-hexane to give compound 19
(210 mg, 94%). M.p. 2768C; [a]D =ꢀ8.0 (c=0.5, THF); 1H NMR
(600 MHz, [D6]acetone): d=8.08–7.33 (m, 10H; 2ꢄPh), 6.95 (d, J-
Ar), 5.96 (d, J
PhCH), 5.41 (d, J
H-1d), 5.21 (dd, J
NHc, CH2, CH2), 4.91 (d, J
11.7 Hz, 1H; CH2), 4.71–4.56 (m, 4H; H-1c, CH2, CH2), 4.43–4.40 (m,
2H; H-6c, H-6d), 4.35 (dd, J(5,6)=7.5 Hz, J(gem)=11.7 Hz, 1H; H-6’d),
4.30–4.25 (m, 2H; H-4b, H-6b), 4.20–3.98 (m, 3H; H-3b, H-6b, H-2d),
3.93 (t, J(5,6)=J(gem)=10.4 Hz, 1H; H-6’c), 3.91–3.88 (m, 2H; H-5b, H-
5d), 3.82 (t, J(3,4)=J(4,5)=9.6 Hz, 1H; H-4c), 3.74 (s, 3H; OMe), 3.64
(q, J(1,2)=J(2,3)=J(2,NH)=8.9 Hz, 1H; H-2c), 3.51 (m, 1H; H-5c),
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
T
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
N
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
A
R
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
1H; H-3b), 3.99 (d, 1H; OH-4b), 3.98–3.96 (m, 2H; H-6b, CH2), 3.90–
3.84 (m, 5H; H-5b, H-6’b, OH-6b, H-4c, H-6’c), 3.77 (ddd, 1H; H-2c),
3.69 (s, 3H; OMe), 3.62 ppm (ddd, JACTHNUTRGENN(UG 4,5)=JAHCUTNGTRENN(GUN 5,6)=9.8 Hz, 1H; H-5c);
A
R
ACHTUNGTRENNUNG
2.21, 2.10, 2.09, and 2.02 ppm (4 s, 12H; 4ꢄAc); 13C NMR (150 MHz,
CDCl3): d=170.9, 170.5, 170.3, 170.3, 170.2, 164.6, 155.5, 154.9, 154.4,
154.0, 151.2, 136.4, 133.6, 129.7, 129.4, 129.3, 128.8, 128.2, 126.1, 118.8,
114.4, 102.5, 101.5, 100.8, 100.4, 96.0, 95.2, 93.9, 79.1, 78.3, 74.6, 74.6, 74.4,
73.1, 72.2, 70.8, 70.6, 70.4, 68.2, 66.5, 66.4, 63.7, 61.0, 57.0, 55.6, 52.7, 29.7,
20.9, 20.8, 20.6 ppm; HRMS (ESI): m/z calcd for C56H59Cl9N2O26+Na+:
1513.0445 [M+Na]+; found: 1513.0445.
13C NMR (150 MHz, [D6]acetone): d=165.7, 156.2, 154.8, 154.5, 152.6,
138.5, 133.8, 131.4, 130.6, 129.7, 129.3, 128.8, 127.1, 119.0, 115.1, 103.2,
101.9, 101.8, 96.8, 95.5, 81.9, 79.3, 77.4, 77.3, 76.3, 74.2, 71.9, 69.6, 69.0,
66.8, 62.1, 57.2, 55.7 ppm; HRMS (ESI): m/z calcd for
C39H39Cl6NO16+Na+: 1010.0292 [M+Na]+; found: 1010.0292.
4-Methoxyphenyl 4,6-O-benzylidene-2-deoxy-2-(2,2,2-
trichloroethoxycarbamoyl)-3-O-(2,2,2-trichloroethoxycarbonyl)-b-d-
glucopyranosyl-(1!3)-6-O-acetyl-2-O-benzoyl-b-d-galactopyranoside
(20)
4-Methoxyphenyl 4,6-O-benzylidene-2-deoxy-2-(2,2,2-
trichloroethoxycarbamoyl)-3-O-(2,2,2-trichloroethoxycarbonyl)-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-4,6-di-O-acetyl-2-deoxy-2-(2,2,2-trichloroethoxycarbamoyl)-b-d-
galactopyranosyl-(1!4)]-6-O-acetyl-2-O-benzoyl-b-d-galactopyranoside
(23)
Ac2O (4.0 mL, 42.4 mmol) and pyridine (10.5 mL, 127 mmol) were added to
a solution of compound 19 (42 mg, 42.4 mmol) in THF (850 mL). The mix-
ture was stirred for 69 h at room temperature (monitored by TLC analy-
sis; CHCl3/MeOH, 20:1), then Ac2O (6.0 mL, 63.6 mmol) and pyridine
(5.2 mL, 63.6 mmol) were added to the mixture and stirring was continued
for 81 h at room temperature (completion of the reaction was confirmed
by TLC analysis; CHCl3/MeOH, 20:1). Then, the reaction mixture was
quenched with MeOH and concentrated under vacuum. The residue was
purified by column chromatography on silica gel (CHCl3/acetone, 15:1!
10:1) to give compound 20 (36 mg, 83%). [a]D =ꢀ2.5 (c=1.0, CHCl3);
1H NMR (600 MHz, CDCl3): d=8.06–7.28 (m, 10H; 2ꢄPh), 6.83–6.65
Molecular sieves (4 ꢂ, 300 mg) were added to a solution of compounds
14 (88 mg, 102 mmol) and 20 (70 mg, 67.8 mmol) in CH2Cl2 (1.7 mL). The
suspension was stirred for 30 min at ꢀ408C, whereupon NIS (34 mg,
153 mmol) and TfOH (1.4 mL, 15.3 mmol) were added. Stirring was contin-
ued for 15 min at ꢀ408C (completion of the reaction was confirmed by
TLC analysis; EtOAc/n-hexane, 1:1; developed twice). The reaction mix-
ture was quenched with saturated aqueous NaHCO3, filtered through
celite, and the molecular sieves were washed with CHCl3. The combined
filtrate and washings were extracted with CHCl3, and the organic layer
was washed with saturated aqueous Na2S2O3, dried (Na2SO4), and con-
centrated under vacuum. The residue was purified by column chromatog-
raphy on silica gel (EtOAc/n-hexane, 1:1) to give compound 23 (99 mg,
82%). [a]D =+7.0 (c=1.0, CHCl3); 1H NMR (600 MHz, CDCl3): d=
(m, 4H; Ar), 5.83 (d, J
7.5 Hz, J(2,3)=9.7 Hz, 1H; H-2b), 5.38 (t, J
H-3c), 5.33 (s, 1H; PhCH), 5.20 (d, J(1,2)=8.3 Hz, 1H; H-1c), 4.88 (d,
1H; H-1b), 4.78 (d, J(gem)=11.7 Hz, 1H; CH2), 4.57 (d, 1H; CH2), 4.46
(dd, (5,6)=7.6 Hz, (gem)=11.7 Hz, 1H; H-6b), 4.43 (dd, (5,6’)=
4.8 Hz, 1H; H-6’b), 4.29 (dd, J(5,6)=4.8 Hz, J(gem)=11.0 Hz, 1H; H-
6c), 4.21 (br s, 1H; H-4b), 4.11 (d, J(gem)=11.7 Hz, 1H; CH2), 4.05 (dd,
(3,4)=3.5 Hz, 1H; H-3b), 3.88 (dd, 1H; H-5b), 3.79 (d, 1H; CH2), 3.73
(dd, J(5,6’)=10.0 Hz, 1H; H-6’c), 3.68 (s, 3H; OMe), 3.63–3.55 (m, 2H;
H-2c, H-5c), 3.51 (t, J(4,5)=9.6 Hz, 1H; H-4c), 2.94 (br s, 1H; OH),
A
ACHTUNGTRNE(NUNG 1,2)=
A
R
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
ACHTUNGTRENNUNG
J
A
J
A
JACHTUNGTRENNUNG
8.07–7.35 (m, 10H; 2ꢄPh), 6.83–6.72 (m, 4H; Ar), 5.95 (d, J
9.0 Hz, 1H; NHd), 5.62–5.57 (m, 2H; H-2b, PhCH), 5.42 (d, J
3.5 Hz, 1H; H-4d), 5.36 (d, J(3,4)=2.7 Hz, 1H; H-4e), 5.26 (d, J
8.2 Hz, 1H; H-1d), 5.21–5.12 (m, 2H; H-3c, H-2e), 5.11 (d, J(2,NH)=
8.9 Hz, 1H; NHc), 4.97–4.85 (m, 4H; H-1b, H-3e, CH2), 4.77 (m, 3H; H-
1c, H-1e, CH2), 4.67 (d, J(gem)=11.6 Hz, 1H; CH2), 4.56 (d, J(gem)=
12.4 Hz, 1H; CH2), 4.46–4.29 (m, 4H; H-4b, H-6c, H-6e, CH2), 4.21–4.16
(m, 5H; H-5b, H-6b, H-6’b, H-3d, H-6d), 4.07 (dd, J(5,6)=6.9 Hz, J-
(gem)=11.0 Hz, 1H; H-6’d), 4.01 (dd, J(2,3)=10.3 Hz, J(3,4)=2.8 Hz,
1H; H-3b), 3.92–3.79 (m, 6H; H-4c, H-6’c, H-2d, H-5d, H-5e, H-6’e),
3.73 (s, 3H; OMe), 3.60 (q, J(1,2)=J(2,3)=8.9 Hz, 1H; H-2c), 3.53 (m,
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
JACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
2.09 ppm (s, 3H; Ac); 13C NMR (150 MHz, CDCl3): d=170.7, 165.5,
155.5, 153.8, 153.8, 151.1, 136.5, 133.5, 129.9, 129.4, 129.1, 128.7, 128.3,
126.0, 118.7, 114.3, 101.5, 101.1, 100.8, 95.4, 94.2, 81.3, 78.2, 75.0, 73.5,
72.1, 70.8, 68.3, 68.3, 66.2, 63.1, 56.6, 55.5, 20.8 ppm; HRMS (ESI): m/z
calcd for C41H41Cl6NO17+Na+: 1052.0398 [M+Na]+; found: 1052.0395.
AHCTUNGTRENNUNG
A
R
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
1H; H-5c), 2.19, 2.16, 2.12, 2.10, 2.09, 2.04, and 1.97 ppm (7s, 21H; 7ꢄ
Ac); 13C NMR (150 MHz, CDCl3): d=170.8, 170.6, 170.3, 170.2, 170.1,
170.0, 169.9, 169.5, 164.6, 155.6, 154.7, 154.5, 153.7, 151.2, 136.3, 133.6,
129.6, 129.4, 129.3, 128.8, 128.2, 126.0, 118.8, 114.3, 102.2, 101.5, 101.3,
100.8, 99.6, 95.8, 95.2, 93.9, 79.3, 78.6, 74.8, 74.6, 74.5, 74.4, 72.5, 72.2,
71.2, 70.8, 70.8, 70.6, 68.5, 68.1, 66.7, 66.3, 63.7, 62.0, 60.7, 57.0, 55.6, 54.6,
20.9, 20.8, 20.8, 20.8, 20.6, 20.5 ppm; HRMS (ESI): m/z calcd for
C68H75Cl9N2O34+Na+: 1801.1290 [M+Na]+; found: 1801.1290.
4-Methoxyphenyl 4,6-O-benzylidene-2-deoxy-2-(2,2,2-
trichloroethoxycarbamoyl)-3-O-(2,2,2-trichloroethoxycarbonyl)-b-d-
glucopyranosyl-(1!3)-{3,4,6-tri-O-acetyl-2-deoxy-2-(2,2,2-
trichloroethoxycarbamoyl)-b-d-galactopyranosyl-(1!4)}-6-O-acetyl-2-O-
benzoyl-b-d-galactopyranoside (22)
Molecular sieves (4 ꢂ, 300 mg) were added to a solution of compounds
21 (38 mg, 65.4 mmol) and 20 (45 mg, 43.6 mmol) in CH2Cl2 (1.1 mL). The
suspension was stirred for 30 min at ꢀ408C, whereupon NIS (22 mg,
98.1 mmol) and TfOH (0.9 mL, 9.8 mmol) were added. Stirring was contin-
ued for 15 min at ꢀ408C (completion of the reaction was confirmed by
Chem. Asian J. 2012, 7, 1041 – 1051
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
1047

H. Ando, M. Kiso et al.
FULL PAPERS
4-Methoxyphenyl 2-acetamido-4,6-O-benzylidene-2-deoxy-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)]-6-
O-acetyl-2-O-benzoyl-b-d-galactopyranoside (24)
1.4 Hz, J
11.6 Hz, 1H; H-3h), 5.05 (dd, J
(1,2)=8.2 Hz, J(2,3)=10.3 Hz, 1H; H-2f), 4.97 (dd, J
H-2e), 4.94 (d, 1H; H-1b), 4.93 (m, 1H; H-4g), 4.89 (d, 1H; H-1f), 4.88
(d, J(1,2)=8.9 Hz, 1H; H-1d), 4.83 (d, J(1,2)=8.9 Hz, 1H; H-1h), 4.71
(d, 1H; H-1e), 4.54–4.50 (m, 2H; H-3f, H-6f), 4.44 (br s, 1H; H-1c), 4.24
(dd, J(5,6)=4.9 Hz, J(gem)=10.4 Hz, 1H; H-6c), 4.21–3.74 (m, 27H; H-
G
ACHTUNGTRENNUNG(2,3)=
AHCTUNGTRENNUNG
R
G
ACHTUNGTRENNUNG
E
ACHTUNGTRENNUNG
Zinc powder (860 mg) was added to a solution of compound 23 (86 mg,
48.2 mmol) in THF (1.6 mL) and AcOH (0.4 mL) and the mixture was
stirred for 40 min at room temperature (completion of the reaction was
confirmed by TLC analysis; CHCl3/MeOH, 20:1). The reaction mixture
was filtered through celite and the zinc powder was washed with EtOAc.
The combined filtrate and washings were extracted with EtOAc, and the
organic layer was washed with saturated aqueous Na2CO3 and brine,
dried (Na2SO4), concentrated under vacuum and exposed to high vacuum
R
ACHTUNGTRENNUNG
3b, H-4b, H-5b, H-6b, H-6’b, H-2c, H-3c, H-4c, H-6’c, H-2d, H-3d, H-5d,
H-6d, H-6’d, H-5e, H-6e, H-6’e, H-4f, H-6’f, H-5g, H-6g, H-9g, H-9g, H-
2h, H-5h, H-6h, H-6h), 3.73 and 3.69 (2s, 6H; 2ꢄOMe), 3.59 (t, J
ACHTUNGTRENNUNG(5,6)=J-
A
R
ACHTUNGTRENNUNG
2.15–1.76 ppm (m, 56H; H-3geq, H-3gax, 18ꢄAc); 13C NMR (150 MHz,
CD3CN): d=171.7, 171.4, 171.2, 171.1, 171.1, 170.9, 170.9, 170.8, 170.7,
170.6, 170.5, 169.3, 166.5, 165.9, 165.3, 156.5, 152.0, 138.5, 134.4, 134.4,
134.2, 131.0, 130.7, 130.6, 130.6, 130.5, 130.2, 129.7, 129.6, 129.5, 129.4,
129.0, 127.1, 119.2, 115.4, 104.1, 103.2, 102.1, 102.1, 102.0, 101.3, 101.2,
100.2, 81.4, 80.1, 79.4, 79,1, 79.0, 78.3, 74.9, 74.1, 73.2, 72.6, 72.5, 72.2,
72.2, 71.8, 71.8, 71.6, 71.4, 71.0, 70.6, 70.3, 69.5, 69.2, 68.6, 68.2, 67.9, 67.6,
67.3, 64.4, 63.9, 63.7, 63.0, 62.2, 62.0, 56.1, 54.0, 51.3, 50.8, 48.7, 35.8, 23.6,
23.3, 23.1, 23.0, 21.4, 21.3, 21.2, 21.1, 21.1, 21.0, 20.9, 20.9, 20.8, 20.6 ppm;
HRMS (ESI): m/z calcd for C117H140N4O57+Na+: 2535.8072 [M+Na]+;
found: 2535.8072.
for 2 h. The residue was treated with
a solution of Ac2O (23 mL,
241 mmol) in CH2Cl2/MeOH (1.0 mL:0.5 mL) for 50 min at room temper-
ature (completion of the reaction was confirmed by TLC analysis;
CHCl3/MeOH, 20:1; developed twice). The mixture was concentrated
under vacuum and the residue was purified by column chromatography
on silica gel (CHCl3/MeOH, 50:1!30:1) to give compound 24 (60 mg,
93%). [a]D =ꢀ12.0 (c=0.5, CHCl3); 1H NMR (600 MHz, CDCl3): d=
8.04–7.36 (m, 10H; 2ꢄPh), 6.89–6.72 (m, 4H; Ar), 6.51 (br s, 1H; NHd),
5.67 (br s, 1H; NHc), 5.60 (dd, J
2b), 5.59 (s, 1H; PhCH), 5.38 (d, J
(3,4)=2.8 Hz, 1H; H-4e), 5.23 (d, J(1,2)=8.2 Hz, 1H; H-1d), 5.12 (dd, J-
(1,2)=7.5 Hz, J(2,3)=10.3 Hz, 1H; H-2e), 4.97 (dd, 1H; H-3e), 4.87 (d,
1H; H-1b), 4.74(d, 1H; H-1e), 4.64 (d, J(1,2)=8.3 Hz, 1H; H-1c), 4.38–
A
ACHTUNGTREN(NUGN 2,3)=9.7 Hz, 1H; H-
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
4-Methoxyphenyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-
d-glycero-a-d-galacto-2-nonulopyranosylonate)-(2!3)-{2-acetamido-
3,4,6-tri-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-
b-d-galactopyranosyl-(1!3)-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)]-6-
O-acetyl-2-O-benzoyl-b-d-galactopyranoside (26)
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
4.30 (m, 4H; H-6c, H-3d, H-6e, H-6’e), 4.22–4.19 (m, 2H; H-4b, H-6d),
4.15–4.09 (m, 3H; H-6b, H-6’b, H-6’d), 3.97–3.85 (m, 5H; H-3b, H-3c, H-
2d, H-5d, H-5e), 3.82–3.78 (m, 2H; H-5b, H-6’c), 3.74 (s, 3H; OMe), 3.62
(ddd, J
G
N
ACHTUNGTRENN(UNG 3,4)=J-
A
R
ACHTUNGTRENNUNG
Compound 25 (82 mg, 32.6 mmol) was treated with a solution of 90%
aqueous AcOH (3.3 mL) for 12 h at 608C (completion of the reaction
was confirmed by TLC analysis; CHCl3/MeOH, 18:1; developed three
times). The reaction mixture was extracted with CHCl3, and the organic
layer was washed with saturated aqueous Na2CO3, dried (Na2SO4), con-
centrated under vacuum, and exposed to high vacuum for 2 h. The diol
derivative was treated with a solution of Ac2O (62 mL, 652 mmol) and
DMAP (1.0 mg, 8.15 mmol) in pyridine (1.1 mL). The mixture was stirred
for 7 h at room temperature (completion of the reaction was confirmed
by TLC analysis; CHCl3/MeOH, 18:1; developed three times). Then the
reaction mixture was quenched with MeOH and concentrated under
vacuum. Then, the mixture was extracted with CHCl3, and the organic
layer was washed with 2m aqueous HCl and saturated aqueous NaHCO3,
dried (Na2SO4), and concentrated under vacuum. The residue was puri-
fied by column chromatography on silica gel (CHCl3/MeOH, 30:1!25:1)
to give compound 26 (79 mg, 96%). [a]D =ꢀ10.0 (c=1.3, CHCl3);
1H NMR (600 MHz, CD3CN): d=8.06–7.48 (m, 15H; 3ꢄPh), 6.83–6.75
H-5c), 3.25 (br s, 1H; OH), 2.16, 2.15, 2.14, 2.11, 2.10, 2.08, 2.03, 1.98,
and 1.77 ppm (9 s, 27H; 9ꢄAc); 13C NMR (150 MHz, CDCl3): d=171.6,
171.2, 170.9, 170.7, 170.6, 170.4, 170.3, 170.2, 169.6, 169.4, 155.6, 151.0,
136.7, 133.7, 129.6, 129.4, 128.8, 128.4, 126.3, 119.2, 114.4, 102.5, 102.0,
100.9, 100.8, 99.9, 81.6, 79.0, 74.6, 73.4, 72.4, 71.5, 71.0, 70.8, 70.5, 69.9,
68.7, 68.4, 66.8, 66.4, 63.8, 62.4, 60.8, 57.6, 55.6, 52.9, 23.6, 23.3, 20.9, 20.8,
20.8, 20.7, 20.7, 20.6 ppm; HRMS (ESI): m/z calcd for C63H76N2O30+Na+:
1363.4375 [M+Na]+; found: 1363.4375.
4-Methoxyphenyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-
d-glycero-a-d-galacto-2-nonulopyranosylonate)-(2!3)-{2-acetamido-
3,4,6-tri-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-
b-d-galactopyranosyl-(1!3)-2-acetamido-4,6-O-benzylidene-2-deoxy-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)]-6-
O-acetyl-2-O-benzoyl-b-d-galactopyranoside (25)
AW-300 molecular sieves (4 ꢂ, 600 mg) were added to a solution of com-
pounds 11 (174 mg, 132 mmol) and 24 (118 mg, 88.0 mmol) in CH2Cl2
(2.2 mL). The suspension was stirred for 30 min at 08C, whereupon
TMSOTf (1.2 mL, 6.60 mmol) was added. The mixture was stirred for 3 h
at 08C (monitored by TLC analysis; CHCl3/MeOH, 18:1; developed
twice), TMSOTf (1.2 mL, 6.60 mmol) was added to the mixture, and stir-
ring was continued for 1 h at 08C (completion of the reaction was con-
firmed by TLC analysis; CHCl3/MeOH, 18:1; developed twice). The reac-
tion mixture was quenched with saturated aqueous NaHCO3, filtered
through celite, and the molecular sieves were washed with CHCl3. The
combined filtrate and washings were extracted with CHCl3, and the or-
ganic layer was washed with saturated aqueous NaHCO3, dried
(Na2SO4), and concentrated under vacuum. The residue was purified by
column chromatography on silica gel (CHCl3/MeOH, 25:1) and column
chromatography on Sephadex LH-20 (CHCl3/MeOH, 1:1) to give com-
pound 25 (179 mg, 81%). [a]D =ꢀ11.5 (c=1.0, CHCl3); 1H NMR
(m, 5H; NHd, Ar), 6.32 (d, J
(2,NH)=9.6 Hz, 1H; NHh), 6.04 (d, J
5.27 (m, 2H; H-2b, H-4h), 5.21–5.20 (m, 2H; H-4d, H-4e), 5.16–5.13 (m,
2H; H-7g, H-8g), 5.12 (dd, J(2,3)=11.0 Hz, J(3,4)=3.5 Hz, 1H; H-3h),
4.98 (d, J(1,2)=8.2 Hz, 1H; H-1b), 4.97 (dd, J(1,2)=7.5 Hz, J(2,3)=
10.3 Hz, 1H; H-2f), 4.91–4.86 (m, 5H; H-4c, H-2e, H-3e, H-4g, H-1h),
4.76 (d, J(1,2)=8.9 Hz, 1H; H-1d), 4.74 (d, 1H; H-1f), 4.53 (dd, J(5,6)=
5.5 Hz, J(gem)=11.7 Hz, 1H; H-6f), 4.49–4.45 (m, 3H; H-3f, H-6’f, H-
1e), 4.26–4.24 (m, 2H; H-1c, H-6e), 4.19 (dd, J(5,6)=5.5 Hz, J(gem)=
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
E
ACHTUNGTRENNUNG
R
G
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
E
ACHTUNGTRENNUNG
12.3 Hz, 1H; H-6c), 4.17–4.09 (m, 4H; H-4b, H-2d, H-2h, H-6h), 4.07–
3.98 (m, 9H; H-6b, H-6’c, H-6d, H-5e, H-6’e, H-5g, H-9g, H-9g, H-5h),
3.97 (d, J
2.7 Hz, 1H; H-3b), 3.92–3.77 (m, 9H; H-6’b, H-2c, H-3c, H-3d, H-5d, H-
6’d, H-5f, H-6g, H-6h), 3.75, and 3.70 (2 s, 6H; 2ꢄOMe), 3.51 (t, J(5,6)=
(5,6’)=6.2 Hz, 1H; H-5b), 3.39 (m, 1H; H-5c), 2.15–1.61 ppm (m, 62H;
ACHTUNGTRNE(UNGN 3,4)=2.8 Hz, 1H; H-4f), 3.94 (dd, JAHCTUNRTGEGUN(NN 2,3)=10.3 Hz, JACHTUNGTRENNUNG(3,4)=
ACHTUNGTRENNUNG
JACHTUNGTRENNUNG
H-3geq, H-3gax, 20ꢄAc); 13C NMR (150 MHz, CD3CN): d=171.6, 171.4,
171.4, 171.4, 171.3, 171.2, 171.2, 171.1, 170.9, 170.9, 170.9, 170.8, 170.5,
170.5, 170.4, 169.2, 167.0, 165.9, 165.4, 156,5, 152.0, 134.5, 134.5, 131.1,
130.8, 130.7, 130.6, 130.5, 130.4, 129.7, 129.6, 129.5, 119.2, 115.4, 104.0,
103.0, 102.4, 102.2, 101.3, 100.8, 100.2, 80.7, 78.5, 76.6, 75.6, 74.5, 73.2,
73.0, 72.6, 72.3, 72.2, 72.1, 72.0, 71.6, 71.5, 71.3, 71.1, 70.5, 70.4, 69.9, 69.3,
68.5, 68.1, 68.0, 67.5, 64.5, 63.3, 62.9, 62.4, 61.8, 56.1, 55.2, 54.0, 51.2, 51.0,
(600 MHz, CD3CN): d=7.95–7.13 (m, 20H; 4ꢄPh), 6.90 (d, J
10.3 Hz, 1H; NHd), 6.83–6.75 (m, 4H; Ar), 6.35 (d, J(2,NH)=9.7 Hz,
1H; NHh), 6.07 (d, J(5,NH)=9.7 Hz, 1H; NHg), 5.93 (d, J(2,NH)=
9.7 Hz, 1H; NHc), 5.59 (s, 1H; PhCH), 5.31 (d, J(3,4)=3.5 Hz, 1H; H-
4e), 5.29 (d, J(3,4)=2.7 Hz, 1H; H-4d), 5.28 (dd, J(1,2)=7.6 Hz, J(2,3)=
9.7 Hz, 1H; H-2b), 5.22 (d, J(3,4)=3.5 Hz, 1H; H-4h), 5.12 (dd, J(6,7)=
ACHTUNGTRNE(NUNG 2,NH)=
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
R
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
1048
www.chemasianj.org
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 2012, 7, 1041 – 1051

A Glucosyl Ceramide Cassette Approach to Gangliosides
48.7, 35.8, 23.5, 23.3, 23.1, 21.4, 21.1, 21.1, 21.1, 21.0, 20.9, 20.9, 20.8,
20.8 ppm; HRMS (ESI): m/z calcd for C114H140N4O59+Na+: 2531.7970
[M+Na]+; found: 2531.7970.
ACHTUNGTNER(NUNG 5,6)=9.2 Hz, JAHCTUNGTRENN(GUN 5,6’)=4.6 Hz, 1H; H-5), 2.72 ppm (s, 1H; OH);
13C NMR (150 MHz, CDCl3): d=165.2, 159.3, 159.2, 133.2, 133.0, 132.3,
130.0, 129.9, 129.7, 129.4, 128.8, 128.4, 127.7, 113.8, 113.8, 86.4, 83.2, 78.3,
74.3, 73.4, 72.1, 72.0, 70.1, 55.3, 55.1 ppm; HRMS (ESI): m/z calcd for
C35H36O8S+Na+: 639.2023 [M+Na]+; found: 639.2023.
Methyl-5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-d-glycero-a-d-
galacto-2-nonulopyranosylonate-(2!3)-{2-acetamido-3,4,6-tri-O-acetyl-2-
deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-b-d-
Phenyl 2-O-benzoyl-4-O-tert-butyldimethylsilyl-3,6-di-O-4-
methoxybenzyl-1-thio-b-d-glucopyranoside (30)
galactopyranosyl-(1!3)-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)]-6-
O-acetyl-2-O-benzoyl-a-d-galactopyranosyl trichloroacetimidate (27)
2,6-Lutidine (283 mL, 2.43 mmol) and TBSOTf (280 mL, 1.22 mmol) were
added to a solution of 29 (500 mg, 811 mmol) in CH2Cl2 (2.7 mL). The
mixture was stirred for 1 h at room temperature (monitored by TLC
analysis; EtOAc/n-hexane, 1:3), 2,6-lutidine (190 mL, 1.62 mmol) and
TBSOTf (186 mL, 811 mmol) were added to the mixture and stirring was
continued for 20 min at room temperature (completion of the reaction
was confirmed by TLC analysis; EtOAc/n-hexane, 1:3). Then the reaction
mixture was quenched with MeOH. The mixture was extracted with
CHCl3, and the organic layer was washed with saturated aqueous
NaHCO3, dried (Na2SO4), and concentrated under vacuum. The residue
was purified by column chromatography on silica gel (EtOAc/n-hexane,
1:7) to give 30 (572 mg, 97%). [a]D =+60.0 (c=1.0, CHCl3); 1H NMR
Diammonium cerium(IV) nitrate (137 mg, 250 mmol) was added to a so-
lution of compound 26 (63 mg, 25.0 mmol) in MeCN/toluene/H2O
(1.1 mL:0.9 mL:0.5 mL) and the mixture was stirred for 1 h at 08C (com-
pletion of the reaction was confirmed by TLC analysis; CHCl3/MeOH,
10:1). The reaction mixture was extracted with EtOAc, and the organic
layer was washed with H2O, saturated aqueous NaHCO3, and brine,
dried (Na2SO4), and concentrated under vacuum. The residue was puri-
fied by column chromatography on silica gel (CHCl3/MeOH, 25:1!20:1)
and column chromatography on Sephadex LH-20 (CHCl3/MeOH, 1:1) to
give 1-OH derivatives. The derivatives were treated with a solution of tri-
chloroacetonitrile (64 mL, 625 mmol) and DBU (3.0 mL, 20.0 mmol) in
CH2Cl2 (500 mL) for 30 min at room temperature (completion of the re-
action was confirmed by TLC analysis; CHCl3/MeOH, 10:1). The mixture
was concentrated under vacuum and the residue was purified by column
chromatography on silica gel (CHCl3/acetone, 1:1) to give 27 (54 mg,
84%). [a]D =+3.6 (c=0.7, CHCl3); 1H NMR (600 MHz, CD3CN): d=
(500 MHz, CDCl3): d=7.99–6.62 (m, 18H; 2 Ph, 2 Ar), 5.27 (t, J
(2,3)=9.2 Hz, 1H; H-2), 4.82 (d, 1H; H-1), 4.60–4.53 (m, 3H; CH2,
CH2), 4.46 (d, J(gem)=11.4 Hz, 1H; CH2), 3.81 (s, 3H; OMe), 3.79 (m,
ACHTUNGTRENNUNG(1,2)=J-
AHCTUNGTRENNUNG
AHCTUNGTRENNUNG
1H; H-6), 3.71–3.57 (m, 7H; H-3, H-4, H-5, H-6’, OMe), 0.86 (s, 9H;
tBu), 0.01 ppm (s, 6H; 2 Me); 13C NMR (125 MHz, CDCl3): d=165.2,
159.1, 158.8, 133.6, 133.1, 131.9, 130.5, 130.0, 129.9, 129.8, 129.2, 128.7,
128.3, 127.4, 113.7, 113.4, 86.2, 84.4, 80.9, 74.8, 73.1, 72.8, 71.2, 69.2, 55.3,
55.0, 25.9, 18.0, ꢀ3.7, ꢀ4.7 ppm; HRMS (ESI): m/z calcd for
C41H50O8SSi+Na+: 753.2888 [M+Na]+; found: 753.2889.
8.88 (s, 1H; C=NH), 8.10–7.45 (m, 15H; 3ꢄPh), 6.66 (d, J
10.3 Hz, 1H; NHd), 6.48 (d, J(1,2)=3.4 Hz, 1H; H-1b), 6.33 (d, J-
(2,NH)=9.0 Hz, 1H; NHc), 6.26 (d, J(2,NH)=9.0 Hz, 1H; NHh), 6.04
(d, J(5,NH)=9.6 Hz, 1H; NHg), 5.33 (dd, J(2,3)=10.3 Hz, 1H; H-2b),
5.28 (d, J(3,4)=2.7 Hz, 1H; H-4h), 5.21–5.20 (m, 2H; H-4d, H-4e), 5.17–
5.14 (m, 2H; H-7g, H-8g), 5.13 (dd, J(2,3)=11.0 Hz, 1H; H-3h), 4.97 (dd,
(1,2)=8.3 Hz, J(2,3)=9.7 Hz, 1H; H-2f), 4.91–4.84 (m, 5H; H-4c, H-2e,
H-3e, H-4g, H-1h), 4.78–4.75 (m, 2H; H-1d, H-1f), 4.56–4.49 (m, 3H; H-
1e, H-6f, H-6’f), 4.48 (dd, J(3,4)=2.8 Hz, 1H; H-3f), 4.31–4.25 (m, 3H;
ACHTUNGTRNE(NUNG 2,NH)=
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
2-O-Benzoyl-4-O-tert-butyldimethylsilyl-3,6-di-O-4-methoxybenzyl-a-d-
glucopyranosyl trichloroacetimidate (31)
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
N-Bromosuccinimide (75 mg, 417 mmol) was added to a solution of 30
(203 mg, 278 mmol) in acetone (2.7 mL)/H2O (0.1 mL). The mixture was
stirred for 15 min at room temperature (completion of the reaction was
confirmed by TLC analysis; EtOAc/n-hexane, 1:3), then the reaction mix-
ture was extracted with EtOAc and the organic layer was washed with sa-
turated aqueous NaHCO3 and brine, dried (Na2SO4), and concentrated
under vacuum. The residue was purified by column chromatography on
silica gel (EtOAc/toluene, 1:7) to give the 1-OH derivatives. The deriva-
J
N
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
H-4b, H-1c, H-6e), 4.23–4.09 (m, 4H; H-3b, H-6c, H-2d, H-2h), 4.07–3.97
(m, 13H; H-6b, H-2c, H-6’c, H-6d, H-5e, H-6’e, H-4f, H-5g, H-9g, H-9g,
H-5h, H-6h, H-6h), 3.88–3.77 (m, 7H; H-6’b, H-3c, H-3d, H-5d, H-6’d, H-
5f, H-6g), 3.75 (s, 3H; OMe), 3.58 (t, JACTHNUGTRNENUG(5,6)=JCAHTUNGTRENN(UGN 5,6’)=6.6 Hz, 1H; H-5b),
3.40 (m, 1H; H-5c), 2.15–1.74 ppm (m, 62H; H-3geq, H-3gax, 20ꢄAc);
13C NMR (150 MHz, CD3CN): d=171.5, 171.4, 171.3, 171.2, 171.2, 171.1,
171.0, 170.9, 170.8, 170.5, 170.5, 170.4, 169.2, 167.0, 166.1, 165.4, 160.8,
134.6, 134.5, 134.4, 131.2, 130.8, 130.7, 130.5, 130.5, 130.4, 130.1, 129.7,
129.7, 129.6, 129.5, 104.2, 103.1, 102.4, 102.2, 100.9, 100.2, 94.6, 91.7, 78.5,
78.4, 77.9, 76.8, 76.2, 74.5, 73.0, 72.7, 72.3, 72.3, 72.2, 72.0, 72.0, 71.6, 71.3,
71.1, 70.5, 70.4, 69.8, 69.3, 69.3, 68.5, 68.1, 68.0, 67.5, 64.8, 64.4, 63.3, 63.0,
62.5, 61.8, 55.2, 54.0, 51.3, 51.0, 48.7, 35.9, 23.4, 23.3, 23.3, 23.1, 21.4, 21.1,
21.1, 21.0, 21.0, 20.9, 20.9, 20.8, 20.8 ppm; HRMS (ESI): m/z calcd for
C109H134Cl3N5O58+Na+: 2568.6648 [M+Na]+; found: 2568.6648.
tives were treated with
a solution of trichloroacetonitrile (560 mL,
5.56 mmol) and DBU (50.0 mL, 334 mmol) in CH2Cl2 (2.8 mL) for 45 min
at room temperature (completion of the reaction was confirmed by TLC
analysis; CHCl3/acetone, 20:1). The mixture was concentrated under
vacuum and the residue was purified by column chromatography on
silica gel (CHCl3/acetone, 70:1!60:1) to give compound 31 (180 mg,
83%). [a]D =+93.0 (c=1.0, CHCl3); 1H NMR (500 MHz, CDCl3): d=
8.46 (s, 1H; C=NH), 7.92–6.63 (m, 13H; Ph, 2ꢄAr), 6.59 (d, J
3.5 Hz, 1H; H-1), 5.35 (dd, J(2,3)=9.7 Hz, 1H; H-2), 4.69 (s, 2H; CH2),
4.54 (d, J(gem)=11.4 Hz, 1H; CH2), 4.46 (d, 1H; CH2), 4.03, (t, J(3,4)=
9.7 Hz, 1H; H-3), 3.99 (m, 1H; H-5), 3.90 (t, J(3,4)=9.7 Hz, 1H; H-4),
ACHTUNGTRENNUNG(1,2)=
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
Phenyl 2-O-benzoyl-3,6-di-O-4-methoxybenzyl-1-thio-b-d-
glucopyranoside (29)
AHCTUNGTRENNUNG
3.81 (s, 3H; OMe), 3.71–3.69 (m, 5H; H-6, H-6’, OMe), 0.88 (s, 9H;
tBu), 0.05 ppm (s, 6H; 2ꢄMe); 13C NMR (125 MHz, CDCl3): d=165.4,
160.6, 159.1, 158.8, 133.2, 130.2, 130.2, 129.7, 129.3, 129.2, 129.0, 128.3,
113.7, 113.4, 94.1, 91.1, 79.6, 75.0, 74.7, 73.0, 72.9, 70.4, 68.1, 55.2, 55.1,
26.0, 18.1, ꢀ3.7, ꢀ4.9 ppm; HRMS (ESI): m/z calcd for
C37H46Cl3NO9Si+Na+: 804.1900 [M+Na]+; found: 804.1900.
Dibutyltin (IV) oxide (3.02 g, 12.1 mmol) was added to a solution of 28
(5.02 g, 10.1 mmol) in toluene (101 mL). The mixture was stirred for 6 h
under reflux conditions, then 4-methoxybenzyl chloride (1.6 mL,
12.1 mmol) and tetrabutylammonium bromide (3.26 g, 10.1 mmol) were
added to the reaction mixture at room temperature. The mixture was
stirred for 13 h under reflux conditions (completion of the reaction was
confirmed by TLC analysis; EtOAc/n-hexane, 1:1), then triethylamine
was added and the mixture was concentrated under vacuum. The residue
was purified by column chromatography on silica gel (CHCl3/MeOH,
150:1). And the residue was recrystallized from EtOAc/n-hexane to give
29 (5.16 g, 83%). M.p. 1048C; [a]D =+19.0 (c=1.0, CHCl3); 1H NMR
2-O-Benzoyl-4-O-tert-butyldimethylsilyl-3,6-di-O-4-methoxybenzyl-b-d-
glucopyranosyl-(1!1)-(2S,3R,4E)-3-O-benzoyl-2-octadecanamido-4-
octadecene-1,3-diol (33)
AW-300 molecular sieves (4 ꢂ, 200 mg) were added to a solution of com-
pounds 31 (47 mg, 60.0 mmol) and 32 (40 mg, 60.0 mmol) in CH2Cl2
(1.2 mL). The suspension was stirred for 30 min at room temperature,
whereupon TMSOTf (1.1 mL, 6.00 mmol) was added. Stirring was contin-
ued for 30 min at room temperature (completion of the reaction was con-
firmed by TLC analysis; EtOAc/n-hexane, 1:3; developed twice). The re-
action mixture was filtered through celite and the molecular sieves were
(500 MHz, CDCl3): d=8.05–6.68 (m, 18H; 2 Ph, 2 Ar), 5.53 (t, J
(2,3)=9.2 Hz, 1H; H-2), 4.79 (d, 1H; H-1), 4.64 (d, J(gem)=11.2 Hz,
1H; CH2), 4.58 (d, 1H; CH2), 4.54 (d, J(gem)=11.5 Hz, 1H; CH2), 4.50
(d, 1H; CH2), 3.82 (s, 3H; OMe), 3.80–3.73 (m, 3H; H-4, H-6, H-6’), 3.71
(s, 3H; OMe), 3.67 (t, J(3,4)=9.2 Hz, 1H; H-3), 3.58 (ddd, J(4,5)=J-
ACHTUNGTRENN(UNG 1,2)=J-
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
Chem. Asian J. 2012, 7, 1041 – 1051
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
1049

H. Ando, M. Kiso et al.
FULL PAPERS
washed with CHCl3. The combined filtrate and washings were extracted
with CHCl3, and the organic layer was washed with saturated aqueous
NaHCO3, dried (Na2SO4), and concentrated under vacuum. The residue
was purified by column chromatography on silica gel (EtOAc/toluene,
1:10) and column chromatography on Sephadex LH-20 (CHCl3/MeOH,
1:1) to give compound 33 (61 mg, 78%). [a]D =+30.0 (c=1.0, CHCl3);
1H NMR (500 MHz, CDCl3): d=8.04–7.39 (m, 10H; 2 Ph), 7.17–6.63 (m,
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
U
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
H-1e, H-3f, H-6’f, CH2), 4.39 (d, 1H; CH2), 4.29–4.25 (m, 2H; H-6e, H-
2Cer), 4.22–4.08 (m, 8H; H-4b, H-1c, H-6c, H-2d, H-2h, H-6h, H-6h, CH2),
4.06–3.95 (m, 8H; H-6b, H-6d, H-5e, H-6’e, H-4f, H-5g, H-9g, H-5h),
3.90–3.87 (m, 2H; H-4a, H-2c), 3.83–3.76 (m, 15H; H-6’b, H-6’c, H-3d,
H-5d, H-6’d, H-5f, H-6g, H-9g, H-1Cer, 2ꢄOMe), 3.70–3.68 (m, 4H; H-3b,
OMe), 3.63–3.59 (m, 3H; H-3a, H-3c, H-5c), 3.51–3.48 (m, 2H; H-5b, H-
8H; 2ꢄAr), 5.83 (dt, J
5Cer), 5.78 (d, J
(2,NH)=9.2 Hz, 1H; NH), 5.54 (t, J
1H; H-3Cer), 5.46 (dd, 1H; H-4Cer), 5.23 (t, J
(1,2)=J
H-2a), 4.61 (d, J(gem)=10.8 Hz, 1H; CH2), 4.57 (d, 1H; CH2), 4.52 (d,
1H; H-1a), 4.43–4.39 (m, 2H; H-2Cer, CH2), 4.28 (d, J
(gem)=12.0 Hz,
1H; CH2), 4.14 (dd, J(1,2)=2.8 Hz, J
(gem)=9.7 Hz, 1H; H-1Cer), 3.80
and 3.70 (2 s, 6H; 2ꢄOMe), 3.69–3.63 (m, 3H; H-3a, H-4a, H-6a), 3.60
(dd, J
(1’,2)=3.4 Hz, 1H; H-1’Cer), 3.51–3.45 (m, 2H; H-5a, H-6’a), 1.99
(m, 2H; H-6Cer, H-6’Cer), 1.72 (m, 2H; NHCOCH2), 1.44–1.09 (m, 52H;
26ꢄCH2), 0.90 (t, J(gem)=6.9 Hz, 6H; 2ꢄCH3), 0.85 (s, 9H; tBu), 0.02
ACHTUNGTREN(UNGN 4,5)=14.9 Hz, JACHUTNRTGEG(NNUN 5,6)=JACUTHNGTRENNUNG
A
R
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
N
1’Cer), 3.45 (dd, J
ACTHNGUTRENN(UG 5,6)=3.9 Hz, JACHTUNGTNER(NUNG gem)=10.7 Hz, 1H; H-6a), 3.30 (d, 1H;
R
H-6’a), 3.19 (m, 1H; H-5a), 2.15–1.74 (m, 66H; H-3geq, H-3gax, H-6Cer, H-
6’Cer, NHCOCH2, 20ꢄAc), 1.39–1.07 (m, 52H; 26ꢄCH2), 0.87 ppm (t, J=
6.9 Hz, 6H; 2ꢄCH3); 13C NMR (150 MHz, CD3CN): d=173.3, 171.5,
171.4, 171.4, 171.3, 171.2, 171.2, 171.1, 171.1, 171.0, 171.0, 170.9, 170.9,
170.8, 170.8, 170.4, 170.4, 169.2, 167.0, 166.1, 165.9, 165.5, 165.5, 160.3,
160.0, 137.5, 134.5, 134.4, 134.3, 134.0, 131.6, 131.4, 131.1, 130.9, 130.9,
130.7, 130.6, 130.5, 130.4, 129.8, 129.7, 129.6, 129.4, 125.4, 114.8, 114.1,
103.9, 103.0, 102.4, 102.4, 102.2, 101.4, 100.8, 100.2, 80.9, 80.8, 78.5, 78.5,
76.6, 76.5, 75.7, 75.4, 75.3, 74.7, 74.5, 73.9, 73.5, 73.0, 72.9, 72.7, 72.3, 72.3,
72.2, 72.1, 72.0, 71.6, 71.3, 71.1, 70.6, 70.4, 70.0, 69.3, 68.5, 68.3, 68.2, 68.1,
68.0, 67.5, 64.6, 64.5, 63.6, 63.3, 63.0, 62.4, 61.8, 56.0, 55.7, 54.0, 51.4, 51.0,
48.7, 36.7, 35.9, 32.8, 32.6, 30.4, 30.2, 30.1, 30.1, 29.8, 29.5, 26.4, 23.5, 23.4,
23.3, 23.1, 21.4, 21.2, 21.1, 21.0, 20.9, 20.8, 20.8, 14.4 ppm; HRMS (ESI):
m/z calcd for 1/2 (C179H237N5O69)+Na+: 1803.2487 [1/2M+Na]+; found:
1803.2487.
A
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
and 0.02 ppm (2 s, 6H; 2ꢄMe); 13C NMR (125 MHz, CDCl3): d=172.7,
165.3, 165.2, 159.1, 158.8, 137.1, 133.2, 132.8, 130.4, 130.1, 129.7, 129.6,
129.2, 129.1, 128.4, 128.3, 124.9, 113.7, 113.4, 100.7, 82.8, 74.5, 74.5, 73.1,
71.1, 68.9, 66.9, 55.2, 55.0, 50.5, 36.4, 32.3, 31.9, 29.7, 29.7, 29.6, 29.6, 29.5,
29.4, 29.4, 29.3, 29.2, 29.0, 25.9, 25.5, 22.7, 17.9, 14.1, ꢀ3.8, ꢀ4.8 ppm;
HRMS (ESI): m/z calcd for C78H119NO12Si+Na+: 1312.8394 [M+Na]+;
found: 1312.8395.
2-O-Benzoyl-3,6-di-O-4-methoxybenzyl-b-d-glucopyranosyl-(1!1)-
(2S,3R,4E)-3-O-benzoyl-2-octadecanamido-4-octadecene-1,3-diol (34)
Methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-d-glycero-a-d-
galacto-2-nonulopyranosylonate-(2!3)-{2-acetamido-3,4,6-tri-O-acetyl-2-
deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-b-d-
galactopyranosyl-(1!3)-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)]-6-
O-acetyl-2-O-benzoyl-b-d-galactopyranosyl-(1!4)-2-O-benzoyl-b-d-
glucopyranosyl-(1!1)-(2S,3R,4E)-3-O-benzoyl-2-octadecanamido-4-
octadecene-1,3-diol (36)
TBAF (1.0m in THF; 140 mL, 140 mmol) and AcOH (2.7 mL, 46.5 mmol)
were added to a solution of compound 33 (60 mg, 46.5 mmol) in THF
(930 mL) and the mixture was stirred for 2.5 h at room temperature (com-
pletion of the reaction was confirmed by TLC analysis; EtOAc/n-hexane,
2:3). The reaction mixture was extracted with EtOAc, and the organic
layer was washed with saturated aqueous NaHCO3 and brine, dried
(Na2SO4), and concentrated under vacuum. The residue was purified by
column chromatography on silica gel (EtOAc/n-hexane >, 2:3) to give
compound 34 (52 mg, 95%).
TFA (200 mL) was added to
a solution of compound 35 (22.5 mg,
The spectropic data of compound 34 were indentical to those reported
6.32 mmol) in CH2Cl2 (400 mL) and the mixture was stirred for 40 min at
08C (completion of the reaction was confirmed by TLC analysis; CHCl3/
MeOH, 15:1; developed twice). The reaction mixture was extracted with
CHCl3, and the organic layer was washed with saturated aqueous
Na2CO3 and brine, dried (Na2SO4), and concentrated under vacuum. The
residue was purified by column chromatography on silica gel (CHCl3/
MeOH, 80:1!20:1) to give compound 36 (20.6 mg, 98%). [a]D =ꢀ6.0
(c=2.0, CHCl3); 1H NMR (600 MHz, CD3CN): d=8.07–7.42 (m, 25H;
previously.[5a]
Methyl-5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-d-glycero-a-d-
galacto-2-nonulopyranosylonate-(2!3)-{2-acetamido-3,4,6-tri-O-acetyl-2-
deoxy-b-d-galactopyranosyl-(1!4)}-2,6-di-O-benzoyl-b-d-
galactopyranosyl-(1!3)-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-
glucopyranosyl-(1!3)-[{2,3,4,6-tetra-O-acetyl-b-d-galactopyranosyl-(1!
3)}-2-acetamido-4,6-di-O-acetyl-2-deoxy-b-d-galactopyranosyl-(1!4)]-6-
O-acetyl-2-O-benzoyl-b-d-galactopyranosyl-(1!4)-2-O-benzoyl-3,6-di-O-
4-methoxybenzyl-b-d-glucopyranosyl-(1!1)-(2S,3R,4E)-3-O-benzoyl-2-
octadecanamido-4-octadecene-1,3-diol (35)
5ꢄPh), 6.71 (d, J
1H; NHc), 6.25 (d, J
8.9 Hz, 1H; NHCer), 6.04 (d, J
H-5Cer), 5.40–5.36 (m, 2H; H-3Cer, H-4Cer), 5.27 (d, J
4h), 5.20 (brs, 1H; H-4e), 5.19 (d, J(3,4)=3.4 Hz, 1H; H-4d), 5.17–5.10
(m, 4H; H-2b, H-7g, H-8g, H-3h), 4.96 (dd, J(1,2)=8.2 Hz, J(2,3)=
9.6 Hz, 1H; H-2f), 4.91 (dd, J(1,2)=7.9 Hz, J(2,3)=9.3 Hz, 1H; H-2a),
4.89–4.83 (m, 5H; H-4c, H-2e, H-3e, H-4g, H-1h), 4.73 (d, 1H; H-1f),
4.68 (d, J(1,2)=9.7 Hz, 1H; H-1d), 4.66 (d, J(1,2)=8.2 Hz, 1H; H-1b),
4.57 (d, 1H; H-1a), 4.54 (dd, J(5,6)=4.9 Hz, J(gem)=11.7 Hz, 1H; H-
6f), 4.48–4.45 (m, 3H; H-1e, H-3f, H-6’f), 4.39 (d, J(3,OH)=2.1 Hz, 1H;
T
ACHTUNGTRENNUNG
N
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
AHCTUNGTRENNUNG
AW-300 molecular sieves (4 ꢂ, 200 mg) were added to a solution of com-
pounds 27 (50 mg, 19.6 mmol) and 34 (35 mg, 29.4 mmol) in CHCl3
(700 mL). The suspension was stirred for 30 min at 08C, whereupon
TMSOTf (0.55 mL, 2.94 mmol) was added. Stirring was continued for 1 h
at 08C (completion of the reaction was confirmed by TLC analysis;
CHCl3/MeOH, 20:1). The reaction mixture was quenched with saturated
aqueous NaHCO3, filtered through celite and the molecular sieves were
washed with CHCl3. The combined filtrate and washings were extracted
with CHCl3, and the organic layer was washed with brine, dried
(Na2SO4), and concentrated under vacuum. The residue was purified by
column chromatography on silica gel (CHCl3/MeOH, 30:1) to give com-
pound 35 (58 mg, 83%). [a]D =ꢀ7.0 (c=0.5, CHCl3); 1H NMR
(600 MHz, CD3CN): d=8.07–7.41 (m, 25H; 5ꢄPh), 7.24–6.63 (m, 9H;
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
OH3a), 4.35 (m, 1H; H-2Cer), 4.26–3.97 (m, 16H; H-4b, H-6b, H-1c, H-6c,
H-6’c, H-2d, H-6d, H-5e, H-6e, H-6’e, H-4f, H-5g, H-9g, H-2h, H-5h, H-
6h), 3.92–3.89 (m, 3H; H-3b, H-2c, H-6h), 3.87–3.73 (m, 13H; H-3a, H-
6’b, H-3c, H-3d, H-5d, H-6’d, H-5f, H-6g, H-9g, H-1Cer, OMe), 3.56–3.50
(m, 3H; H-4a, H-5b, H-1’Cer), 3.39 (m, 1H; H-5c), 3.28 (m, 1H; H-5a),
3.18 (m, 1H; H-6a), 3.12 (m, 1H; H-6’a), 2.56 (br t, 1H; OH6a), 2.15–1.74
(m, 66H; H-3geq, H-3gax, H-6Cer, H-6’Cer, NHCOCH2, 20ꢄAc), 1.41–1.10
(m, 52H; 26ꢄCH2), 0.88 ppm (t, J=6.9 Hz, 6H; 2ꢄCH3); 13C NMR
(150 MHz, CD3CN): d=173.5, 171.5, 171.5, 171.4, 171.3, 171.3, 171.2,
171.2, 171.2, 171.1, 171.0, 170.9, 170.9, 170.8, 170.8, 170.5, 170.5, 170.4,
169.2, 167.0, 166.3, 166.1, 165.8, 165.5, 137.8, 134.5, 134.5, 134.2, 134.1,
131.3, 131.2, 131.0, 130.9, 130.8, 130.5, 130.5, 130.4, 130.3, 129.8, 129.6,
129.6, 129.4, 125.1, 103.9, 103.1, 102.8, 102.5, 102.2, 101.1, 100.8, 100.2,
NHd, 2ꢄAr), 6.26 (d, J
8.9 Hz, 1H; NHh), 6.07 (d, J
(5,NH)=9.6 Hz, 1H; NHg), 5.61 (dt, J
7.1 Hz, 1H; H-5Cer), 5.37–5.33 (m, 2H; H-3Cer, H-4Cer), 5.27 (d, J
2.7 Hz, 1H; H-4h), 5.21 (d, J(3,4)=3.5 Hz, 1H; H-4d), 5.18 (d, J
1.4 Hz, 1H; H-4e), 5.16–5.10 (m, 4H; H-2b, H-7g, H-8g, H-3h), 4.98 (dd,
(1,2)=7.6 Hz, J(2,3)=9.6 Hz, 1H; H-2f), 4.92 (dd, J(1,2)=8.2 Hz, J-
A
ACHTUNGTRNE(NUNG 2,NH)=
AHCTUNGTRENNUNG
A
E
N
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
J
N
N
ACHTUNGTRENNUNG
1050
www.chemasianj.org
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Asian J. 2012, 7, 1041 – 1051

A Glucosyl Ceramide Cassette Approach to Gangliosides
82.8, 80.6, 78.6, 78.5, 76.7, 75.4, 75.3, 74.6, 74.5, 74.1, 73.1, 73.0, 72.7, 72.3,
72.2, 72.1, 72.0, 71.6, 71.4, 71.3, 71.1, 70.4, 69.9, 69.3, 68.5, 68.4, 68.1, 68.0,
67.5, 64.5, 64.3, 63.2, 63.0, 62.5, 61.8, 61.2, 55.1, 54.0, 51.4, 51.2, 51.0, 48.7,
36.8, 35.9, 32.8, 32.6, 30.4, 30.3, 30.2, 30.1, 30.1, 29.8, 29.5, 26.5, 23.5, 23.4,
23.3, 23.2, 23.1, 21.4, 21.1, 21.0, 20.9, 20.8, 20.8, 20.7, 14.4 ppm; HRMS
(ESI): m/z calcd for 1/2 (C163H221N5O67)+Na+: 1683.1912 [1/2M+Na]+;
found: 1683.1912.
22380067, respectively, to M.K., and a grant-in-aid for Young Scientists
(A), No. 23688014, to H.A.). We thank Dr. Rita Pal for fruitful discus-
sions and Dr. Yuji Kamatari of the Division of Instrumetanl Analysis of
Gifu University and Ms. Kiyoko Ito for providing technical assistance.
[1] N. Yuki, S. Sato, T. Miyatake, K. Sugiyama, T. Katagiri, H. Sasaki,
Lancet 1991, 337, 1109–1110.
[2] N. Yuki, T. Miyatake, Y. Ichihashi, S. Sato, T. Katagiri, Muscle
Nerve 1992, 15, 1371–1373.
Ganglioside X2 (2)
A solution of sodium methoxide (28% in MeOH, 1.0 mg) was added to a
solution of compound 36 (49.8 mg, 15.0 mmol) in MeOH (1.0 mL). The
mixture was stirred for 75 h at room temperature (monitored by TLC
analysis; CHCl3/MeOH/12 mm MgCl2 (aq.), 5:4:1), H2O was added to the
mixture, and stirring was continued for 93 h at 408C (monitored by TLC
analysis; CHCl3/MeOH/12 mm MgCl2 (aq.), 5:4:1). Then 0.2m NaOH
(aq.) was added to the mixture and stirring was continued for 72 h at
408C (completion of the reaction was confirmed by TLC analysis;
CHCl3/MeOH/12 mm MgCl2 (aq.), 5:4:1). After neutralization with
Dowex-50 (H+), the mixture was filtered through cotton wool, and the
resin was washed with MeOH. The combined filtrate and washings were
concentrated under vacuum. The residue was purified by column chroma-
tography on Sephadex LH-20 (MeOH) and column chromatography on
Iatrobeads 6RS-8060 (CHCl3/MeOH/H2O, 5:4:0.8!5:4:1) to give com-
[3] T. Nakao, K. Kon, S. Ando, T. Miyatake, N. Yuki, Y.-T. Li, S.
Furuya, Y. Hirabayashi, J. Biol. Chem. 1993, 268, 21028–21034.
[4] S. Nakashima, H. Ando, A. Imamura, N. Yuki, H. Ishida, M. Kiso,
Chem. Eur. J. 2011, 17, 588–597.
[5] a) A. Imamura, H. Ando, H. Ishida, M. Kiso, J. Org. Chem. 2009,
74, 3009–3023; b) K. Fujikawa, T. Nohara, A. Imamura, H. Ando,
H. Ishida, M. Kiso, Tetrahedron Lett. 2010, 51, 1126–1130; c) K. Fu-
jikawa, S. Nakashima, M. Konishi, T. Fuse, N. Komura, T. Ando, H.
Ando, N. Yuki, H. Ishida, M. Kiso, Chem. Eur. J. 2011, 17, 5641–
5651.
[6] T. Fuse, H. Ando, A. Imamura, S. Sawada, H. Ishida, M. Kiso, T.
Ando, S.-C. Li, Y.-T. Li, Glycoconjugate J. 2006, 23, 329–343.
[7] J.-C. Jacquinet, Carbohydr. Res. 2006, 341, 1630–1644.
[8] K. Furusawa, Chem. Lett. 1989, 509–510.
[9] T. Yoshikawa, Y. Kato, N. Yuki, T. Yabe, H. Ishida, M. Kiso, Glyco-
conjugate J. 2008, 25, 545–553.
pound
2
(30.6 mg, 97%). [a]D =ꢀ3.0 (c=0.5, MeOH); 1H NMR
(600 MHz, CD3OD): d=5.68 (dt,
JACHTUNRTGEG(NUNN 4,5)=15.2 Hz, JACHTUNTGRENNUG(5,6)=JACHTUTNGRENNUG(5,6’)=
ACTHNUTRGNEUNG
6.9 Hz, 1H; H-5Cer), 5.44 (dd, J(3,4)=7.6 Hz, 1H; H-4Cer), 4.94 (d, J=
9.0 Hz, 1H; anomeric H), 4.86–4.85 (m, 1H; anomeric H), 4.60 (d, J=
8.9 Hz, 1H; anomeric H), 4.49 (d, J=7.6 Hz, 1H; anomeric H), 4.44 (d,
J=8.3 Hz, 1H; anomeric H), 4.32 (d, J=8.3 Hz, 1H; anomeric H), 4.29
(d, J=7.5 Hz, 1H; anomeric H), 2.75 (dd, J
12.4 Hz, 1H; H-3geq), 2.16 (t, J=7.6 Hz, 2H; NHCOCH2), 2.02–1.99 (m,
14H; H-6Cer, H-6’Cer, 4ꢄAc), 1.89 (t, J
(3ax,4)=12.4 Hz, 1H; H-3gax), 1.57
[10] a) P. Konradsson, U. E. Udodong, B. Fraser-Reid, Tetrahedron Lett.
1990, 31, 4313–4316; b) P. Konradsson, D. R. Mootoo, R. E. McDe-
vitt, B. Fraser-Reid, J. Chem. Soc. Chem. Commun. 1990, 270–272;
c) G. H. Veeneman, S. H. Van Leeuwen, J. H. Van Boom, Tetrahe-
dron Lett. 1990, 31, 1331–1334.
ACHUTGTNRENN(UG 3eq,4)=4.9 Hz, JACHTUNGTERN(NUGN gem)=
AHCTUNGTRENNUNG
(m, 2H; NHCOCH2CH2), 1.39 (m, 2H; H-7Cer, H-7’Cer), 1.33–1.29 (m,
48H; 24ꢄCH2), 0.90 ppm (t, J=6.9 Hz, 6H; 2ꢄCH3); 13C NMR
(150 MHz, CD3OD): d=175.9, 175.7, 175.0, 174.7, 174.7, 135.1, 131.4,
106.4, 105.3, 104.6, 104.4, 104.3, 104.1, 103.3, 103.2, 84.4, 83.2, 81.9, 80.9,
78.9, 77.7, 76.7, 76.7, 76.5, 76.5, 76.3, 76.1, 76.0, 75.9, 75.9, 75.1, 74.9, 74.6,
74.3, 73.3, 73.0, 72.6, 71.3, 70.8, 70.4, 70.1, 70.0, 69.9, 69.6, 65.4, 63.1, 62.9,
62.8, 62.4, 62.0, 61.9, 61.7, 55.9, 54.7, 54.3, 53.8, 52.7, 49.6, 38.8, 37.4, 33.5,
33.1, 33.1, 30.9, 30.8, 30.8, 30.8, 30.7, 30.6, 30.5, 30.5, 30.4, 27.2, 23.8, 23.6,
23.6, 22.6, 14.5 ppm; HRMS (ESI): m/z calcd for C95H167N5O46-H:
2113.0809 [MꢀH]ꢀ; found: 2113.0810.
[11] M. Nitz, D. R. Bundle, J. Org. Chem. 2000, 65, 3064–3073.
[12] Y. Matsuzaki, Y. Ito, Y. Nakahara, T. Ogawa, Tetrahedron Lett.
1993, 34, 1061–1064.
[13] a) K. K. Sadozai, T. Nukada, Y. Ito, Y. Nakahara, T. Ogawa, Carbo-
hydr. Res. 1986, 157, 101–123; b) T. Ogawa, M. Sugimoto, T. Kitaji-
ma, K. K. Sadozai, T. Nukada, Tetrahedron Lett. 1986, 27, 5739–
5742.
[14] K. Fujikawa, A. Imamura, H. Ishida, M. Kiso, Carbohydr. Res. 2008,
343, 2729–2734.
[15] a) M. Kiso, A. Nakamura, Y. Tomita, A. Hsegawa, Carbohydr. Res.
1986, 158, 101–111; b) M. Kiso, A. Nakamura, J. Nakamura, Y.
Tomita, A. Hsegawa, J. Carbohydr. Chem. 1986, 5, 335–340.
[16] H. Shimizu, Y. Iwayama, A. Imamura, H. Ando, H. Ishida, M.
Kiso, Biosci. Biotechnol. Biochem. 2011, 75, 2079-2082.
Acknowledgements
This work was financially supported by MEXT, Japan (WPI program and
grant-in-aid for Scientific Research (S) and (B), No. 1701007 and
Received: November 12, 2011
Published online: February 14, 2012
Chem. Asian J. 2012, 7, 1041 – 1051
ꢁ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
1051