Synthesis of three Salmonella epitopes for biosensor studies of carbohydrate-antibody interactions

Article abstract of DOI:10.1139/v02-121

Disaccharides 1-3 corresponding to the antigenic determinants of Salmonella serotypes A, B, and D₁ were synthesized in a form suited for use in biosensors. The disaccharide determinants each contain a unique 3,6-dideoxyhexose, namely abequose (

Full text of DOI:10.1139/v02-121

1131
Synthesis of three Salmonella epitopes for
biosensor studies of carbohydrate–antibody
interactions
Henry N. Yu, Chang-Chun Ling, and David R. Bundle
Abstract: Disaccharides 1–3 corresponding to the antigenic determinants of Salmonella serotypes A, B, and D1 were
synthesized in a form suited for use in biosensors. The disaccharide determinants each contain a unique 3,6-
dideoxyhexose, namely abequose (3,6-dideoxy-D-xylo-hexose), paratose (3,6-dideoxy-D-ribohexose), and tyvelose
(3,6-dideoxy-D-arabino-hexose), are ꢀ-linked to the 3-position of D-mannopyranose. The disaccharides were further
derivatized with a linear aglycon that has a terminal amino group, and can be readily coupled to pertinent chains
carrying a terminal thiol for the construction of self-assembled monolayers (SAMs). Efficient routes that employed a
single 3,6-dideoxygenation step were developed for the synthesis of paratoside 15 and tyveloside 22.
Key words: Salmonella O-antigens, lipopolysaccharide, abequose, paratose, tyvelose, 3,6-dideoxyhexose, deoxygenation,
glycoside tethers, immobilization via pentenyl glycosides.
Résumé : On a synthétisé des formes appropriées à un usage comme biosenseurs des disaccharides 1–3, qui
correspondent aux déterminants antigéniques de la Salmonella de sérotypes A, B et D1. Les déterminants disaccharides
comportent chacun un 3,6-didésoxyhexose unique, soit l’abéquose (3,6-didésoxy-D-xylo-hexose), le paratose (3,6-
didésoxy-D-ribo-hexose) et le tyvelose (3,6-didésoxy-D-arabino-hexose), ainsi qu’une liaison ꢀ à la position 3 du D-
mannopyranose. On en a ensuite préparé des dérivés à l’aide d’une aglycone linéaire portant un groupe amino terminal;
ces dérivés peuvent facilement être couplés à des chaînes appropriées portant une fonction thiol terminale pour la con-
struction de monocouches autoassemblées (MAA). On a développé des voies efficaces de synthèse du paratoside 15 et
du tyveloside 22 qui font appel à une réaction permettant d’effectuer une 3,6-didéoxygénation en une seule étape.
Mots clés : O-antigènes de la Salmonella, lipopolysaccharide, abéquose, paratose, tyvelose, 3,6-didésoyxhexose,
désoxygénation, téthères glycosidiques, immobilisation via des glycosides de pentényle.
[Traduit par la Rédaction] Yu et al. 1140
Introduction
Ka as well as a complete thermodynamic description,
enthalpy (ꢁH), and entropy (ꢁS) for reactions in solution.
However, the drawback of this method is the requirement
for large amounts of protein sample, typically 10–25 mg of
relatively pure protein per measurement (3, 17). Surface
plasmon resonance (SPR) has emerged as an alternative
since it was first reported in the early 1990s (4, 18). This ex-
tremely sensitive technique is able to provide a value of Ka
from on and off rates (5). Whitesides and co-workers were
the first to use alkanethiolates to form self-assembled
monolayers (SAMs) on gold surfaces for SPR analysis (6).
This technique represents several advantages over other
coating methods: (i) monolayers prepared from alkanethiols
terminated in oligo(ethylene glycol) groups are inert to the
nonspecific adsorption of protein (7, 8); (ii) linkers with de-
fined length can be easily tailored chemically before attach-
ment to the gold surface; and (iii) ligands are presented in a
homogenous environment where their density can be easily
Structural and thermodynamic studies of carbohydrate–
protein interactions have played a fundamental role in the
development of an understanding of the features of a variety
of carbohydrate-based biological recognition systems (1).
Although a few examples of carefully designed carbohydrate
clusters, such as the decameric Escherichia coli toxin inhibi-
tor, Starfish (2), have demonstrated extraordinary association
constants, carbohydrates generally exhibit association con-
stants for proteins in the millimolar to micromolar range.
Since carbohydrates are normally devoid of convenient spec-
troscopic reporter groups, convenient methods for the accu-
rate and rapid measurement of these relatively weak
interactions (affinity) are limited. Traditionally, solid-phase
enzyme immunoassays (EIA) have been employed to give an
indirect estimate of the association constant (Ka) (3). Titra-
tion microcalorimetry provides a very accurate measure of
Received 4 December 2001. Published on the NRC Research Press Web site at http://canjchem.nrc.ca on 28 August 2002.
We dedicate this paper to the memory of Professor Raymond U. Lemieux.
H.N. Yu, C.-C. Ling, and D.R. Bundle.1 Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
1Corresponding author (e-mail: dave.bundle@ualberta.ca).
Can. J. Chem. 80: 1131–1140 (2002)
DOI: 10.1139/V02-121
© 2002 NRC Canada

1132
Can. J. Chem. Vol. 80, 2002
Fig. 1. Three disaccharide antigenic determinants of Salmonella
serogroups B (1), A (2), and D1 (3) derivatized for conjugation
to biosensors.
Scheme 2. (a) EtSH, BF3·Et2O, CH2Cl2; (b) (i) NaOMe, MeOH;
(ii) BnBr, NaH, DMF.
Ph
OH
HO
O
O
HO
BnO
BnO
O
O
O
O
a
6 steps
O
O
HO
O
S
Ref (21)
R
NH2
OAcOAc
8
OR SEt
9 R=Ac
10 R=Bn
O
b
HO
HO
R =
HO
HO
O
OH
O
O
duct glycosylation under the promotion of N-iodo-
succinimide. Fraser-Reid et al. (19, 20) have also developed
an armed–disarmed strategy to synthesize oligosaccharides
using this group. The group has appeal due to its linear
structure and its terminal double bond that can be further
derivatized to extend the linear chain, while remaining con-
sistent with orthogonal protection strategies for the introduc-
tion of other functional groups during elaboration of
oligosaccharides. In the context of the target disaccharides
1–3, glycosyl acceptor 7 was identified as convenient
synthon. As shown in Scheme 1, compound 7 was synthe-
sized from 4-pentenyl ꢀ-D-mannopyranoside 4 (19). The 3-
position was selectively protected as the p-methoxybenzyl
ether under di-n-butyltin oxide activation (J5, 60%). The
remaining hydroxyl groups were benzylated (J6, 76%). Af-
ter removal of the p-methoxybenzyl group with ceric ammo-
nium nitrate, the desired acceptor 7 was obtained in good
yield (72%).
HO
3
2
1
Scheme 1. (a) (i) Bu2SnO, toluene, reflux; (ii) p-MBnCl, Bu2NBr,
toluene, 60°C; (b) BnBr, NaH, DMF; (c) CAN, CH3CN–H2O.
OH
OH
O
OBn
OBn
O
b
HO
RO
BnO
RO
OPent
OPent
4 R=H
5 R=MBn
6 R=MBn
7 R=H
a
c
Pent =
We next turned our attention to methods for the rapid and
convenient synthesis of the abequose, paratose, and tyvelose
donors 10, 16, and 23, respectively. As all the three 3,6-
dideoxyhexose units adopt the ꢀ-configuration, we employed
a nonparticipating benzyl ether group to protect the 2-position.
Our recent published synthetic route to abequose allowed us
to prepare the rare hexose in large quantity (Scheme 2) (21).
The desired thioabequoside 10 was prepared from diacetate
8 (21). The anomeric O-acetate was first transformed to the
thioethyl glycoside using a conventional method to afford
the thioglycoside 9 as an anomeric mixture (ꢀ/ꢂ (1:3), 95%).
The 2-O-acetyl group was then replaced with a benzyl group
by first transesterifying the acetate, followed by benzylation
of the intermediate alcohol to give 10 (22) in 92% overall
yield for these two transformations.
The paratose methyl glycoside 12 was prepared from a
known dibromide 11 (Scheme 3) (23). In the literature the
dibromo-dideoxy hexose was reduced by catalytic hydroge-
nation in 85% yield. Barton–McCombie radical deoxygena-
tion conditions (24) converted 11 into diol 12 in near
quantitative yield (98%). After acetylation (J13) (25), this
glycoside was subjected to acetolysis to yield the tri-O-ace-
tate 14, in 94% yield. Glycosidation with ethanethiol af-
forded thioglycoside 15 (75%, ꢀ/ꢂ (1:3)). The benzylated
thioglycoside was finally prepared by a conventional two-
step transformation sequence (J16, 78%).
controlled. Experiments varying the linker length and carbo-
hydrate density have been reported recently to probe the
multivalency effect (9–11).
We report here the synthesis of three functionalized
disaccharides (1–3), which are readily available for coupling
to
a pertinent chain carrying a terminal thiol. The
functionalized disaccharide glycosides can then be conju-
gated to a gold surface to form SAMs for SPR or other bio-
sensor analysis (12) (Fig. 1). These disaccharides are located
in the O-antigen segment of the lipopolysaccharide compo-
nent of the Salmonella cell wall (13). The 3,6-
dideoxyhexoses function as the principal structural elements,
antigenic determinants, or epitopes recognized by antibod-
ies. Following cases of Salmonella food poisoning patient
sera contains antibodies specific for the LPS O-antigen of
the infecting bacterium. In the case of infection by Salmo-
nella of serotypes A, B, and D1, the antibodies bind and rec-
ognize disaccharides with terminal paratose, abequose, and
tyvelose residues (14). The structural (15) and thermody-
namic aspects (16, 17) of the abequose trisaccharide binding
to monoclonal antibody Se155-4 have been well character-
ized by our group. SPR or other biosensor analysis using
SAMs would provide a highly sensitive method to secure
sensitive, rapid, and accurate measurement of association
constants to complement our recent SPR analysis of anti-
body binding sites using a BSA-O-polysaccharide conju-
gates as the stationary phase (18).
We have published a method to synthesize a tyvelose do-
nor from methyl ꢀ-glucopyranoside via an eight-step reac-
tion sequence (26). A more concise synthesis of this
dideoxyhexose was desired and we chose to exploit selectively
benzoylated mannose derivatives to achieve this objective in
four steps. It is known that when mannopyranosides are
treated with excess trimethyl orthobenzoate in the presence
Results and discussion
The 4-pentenyl group was introduced by Fraser-Reid’s
group (19) as a versatile and temporary protecting group for
the anomeric position of sugars. It can be activated to con-
© 2002 NRC Canada

Yu et al.
1133
Scheme 3. (a) Bu3SnH, AlBN, toluene, reflux; (b) Ac2O, pyridine; (c) Ac2O, H2SO4 (cat.); (d) EtSH, BF3·Et2O, CH2Cl2;
(e) (i) NaOMe, MeOH; (ii) BnBr, NaH, DMF.
OH
Br
Tribromoimidazole,
Ph3P, toluene
Ref (23)
O
O
O
RO
a
HO
HO
HO
OR
OH
OMe
OH
OMe
OMe
Br
11
12 R=H
13 R=Ac
b
c
O
d
O
RO
AcO
SEt
OAc
OR
15 R=Ac
16 R=Bn
OAc
14
e
Scheme 4. (a) NaOMe, MeOH; then Etl; (b) (i) PhC(OMe)3, CSA, CHCl3; (ii) 90% AcOH – H2O; (c) 1,1>-thiocarbonyldiimidazole, to-
luene, reflux; (d) Bu3SnH, AlBN, toluene, reflux; (e) (i) NaOMe, MeOH; (ii) NaH, BnBr, DMF.
OR1
OR1
O
OBz
OBz
O
OH
OBz
O
b
+
R1O
R1O
HO
HO
BzO
HO
SEt
SEt
SR2
19
20
17 R1=Ac, R2=Ac
18 R1=H, R2=Et
a
c
S
N
N
O
OBz
OR
O
O
d
BzO
S
RO
N
SEt
SEt
O
N
22 R=Bz
23 R=Bn
21
e
the literature when the authors attempted to deoxygenate a
3,6-anhydro-galactopyranosyl derivative bearing two
phenoxythiocarbonyl groups at the 2,4-positions (29).
Normally, having a participating group at the O-2 position,
donor 22 should be suitable for the preparation of ꢀ-
tyveloside. However, in our acceptor, we have a 4-pentenyl
group at the anomeric centre; preliminary studies demon-
strated that when MeOTf was used to activate 22 for the
glycosylation of 7, orthoester was formed; when NIS–TfOH
was used, the 4-pentenyl group was decomposed by the re-
agent. We thus decided to prepare the corresponding
benzylated donor 23, thereby allowing us to use MeOTf as
activating reagent (30) and avoid the formation of
orthoester. The benzoyl groups of 22 were replaced by
benzyl groups as before to afford the tyvelose donor 23 in
excellent yield (95%).
With all three 3,6-dideoxyhexose donors (10, 16, and 23)
and the mannopyranosyl acceptor 7 in hand, glycosylations
were carried out (Scheme 5). Coupling of 10 with 7 under
activation by methyl triflate and 2,6-di-tert-butyl-4-
methylpyridine in Et2O afforded disaccharide 24 (82%),
with excellent anomeric selectivity (ꢀ/ꢂ, 40:1). Compound
16 was glycosidated by 7 in a similar fashion to give 25 in
good yield, but poor stereoselectivity (80%, ꢀ/ꢂ (3:2)).
of acid followed by hydrolysis, two dibenzoylated com-
pounds are obtained as the major products; one is the 2,4-di-
O-benzoate, and the other is the corresponding 2,6-isomer
(27, 28). Ethyl 1-thio-ꢂ-D-mannopyranoside 18 was pre-
pared in 96% yield from 2,3,4,6-tetra-O-acetyl-1-S-acetyl-1-
thio-ꢂ-D-mannopyranose (17) following our published meth-
odology (28) (Scheme 4). Treatment of the ꢂ-thiomannoside
18 with excess trimethyl orthobenzoate in the presence of
camphorsulphonic acid followed by opening of the interme-
diate orthoesters with 90% acetic acid – water afforded the
undesired 2,6-dibenzoylated product 19 (43%) and the
desired 2,4-dibenzoylated product 20 (44% yield). After ac-
tivating the OH-3 and OH-6 groups in 20 using imidazolyl-
thiocarbonyl groups (J21, 76%), the tyveloside 22 was
obtained in 45% yield using Barton radical deoxygenation
conditions with tri-n-butyltin hydride as reducing agent in
boiling toluene. Attempts to increase the yield by varying
reaction conditions failed. To rule out the possibility that the
thioethyl group might be complicating the radical reaction,
the O-methyl glycoside analogue of compound 22, methyl
2,4-di-O-benzoyl-3,6-di-O-(imidazolylthiocarbonyl)-ꢀ-D-
mannopyranoside, was synthesized and subjected to the
same deoxygenation condition (data not reported) and a sim-
ilar yield was obtained. A comparable yield was reported in
© 2002 NRC Canada

1134
Can. J. Chem. Vol. 80, 2002
Scheme 5. (a) MeOTf, DTBMP, Et2O, 0°C; (b) Na, NH3 (liquid), MeOH, –78°C; (c) HSCH2CH2NHꢄ3 Cl–, MeOH, UV light (254 nm).
OBn
OBn
O
OH
OH
O
BnO
R4
HO
R4
O
O
a
b
10, 16, or 23
7
+
OPent
OPent
R2
R2
O
O
R3
R3
R1
R1
27 R1 = OH, R2 = H, R3 = H, R4 = OH
28 R1 = H, R2 = OH, R3 = H, R4 = OH
29 R1 = H, R2 = OH, R3 = OH, R4 = H
24 R1 = OBn, R2 = H, R3 = H, R4 = OBn
25 R1 = H, R2 = OBn, R3 = H, R4 = OBn
26 R1 = H, R2 = OBn, R3 = OBn, R4 = H
c
1, 2, 3
Disaccharide 26 was obtained in the same fashion (70%)
with excellent stereoselectivity; no ꢂ-isomer was detected.
Debenzylation for all three disaccharides was smoothly car-
ried out by Birch reduction with preservation of the terminal
double bond of the 4-pentenyl group provided that the reac-
tion temperature was kept at –78°C. Reverse-phase HPLC
allowed complete separation of the anomeric isomers (J27
(100%), J28 (47%ꢀ + 33%ꢂ), J29 (84%)). The anomeric
configuration of the protected and deprotected disaccharide
products were confirmed by measurement of the one-bond
heteronuclear coupling constant JC1,H1 (31), since the J1,2
homonuclear coupling constants would not distinguish the ꢀ-
and ꢂ-tyvelose anomers.
The elongation and functionalization of the aglycon was
achieved through photoaddition of cysteamine hydrochloride
(32) to the terminal double bond to afford the desired target
disaccharides 1 (90%), 2 (71%), and 3 (94%).
2487 UV detector or a Waters 2410 refractive index
monitor. Microanalyses and electrospray mass spectra were
performed by the analytical services of this department.
4-Pentenyl 3-O-p-methoxybenzyl-ꢀ-D-mannopyranoside
(5)
To a solution of 4-pentenyl ꢀ-D-mannopyranoside 4 (19)
(6.86 g, 27.6 mmol) in anhydrous toluene (120 mL), was
added di-n-butyltin oxide (7.56 g, 29.8 mmol); the mixture
was refluxed with azeotropic removal of water for 6 h using
a Dean–Stark tube. The reaction was cooled to 60°C, tetra-
n-butylammonium bromide (9.79 g, 30.1 mmol) and 4-
methoxybenzyl chloride (4.13 mL, 30.4 mmol) were added,
and the reaction was stirred for 16 h at the same tempera-
ture. The mixture was concentrated and the residue was pu-
rified by column chromatography on silica gel (MeOH–
EtOAc, 19:1 v/v), to give compound 5 (6.1 g, yield 60%).
1
3
1
[ꢀ]2D2 +18.5 (c 2.6, CHCl3). H NMR (CDCl3, 300 MHz) ꢃ:
In summary, three immunodominant disaccharide epitopes
present in the O-antigens of Salmonella LPS were synthe-
sized as their 4-pentenyl glycosides and were functionalized
for incorporation into SAMs. SPR studies with these com-
pounds are in progress and will be reported in due course.
7.28–6.84 (m, 4H, MBn), 5.76 (ddt, J = 6.5, 10.2, 16.9 Hz,
1H, CH=CH2), 4.96 (m, 2H, CH=CH2), 4.77 (d, J =
1.1 Hz, 1H, H-1), 4.54 (d, J = 11.2 Hz, 1H, MBn), 4.49 (d,
1H, MBn), 4.00–3.30 (m, 8H, H-2 + H-3 + H-4 + H-5 + H-6 +
OCH2CH2), 2.05 (m, 2H, CH2CH=CH2), 1.61 (m, 2H,
OCH2=CH2). HR-ES-MS calcd. for C19H28O7Na+:
391.173273; found: 391.172706.
Experimental
Optical rotations were measured with a PerkinElmer 241
polarimeter at 22 ± 2°C. Analytical TLC was performed on
Silica Gel 60-F254 (E. Merck, Darmstadt) with detection by
quenching of fluorescence and (or) by charring with sulfuric
acid. All commercial reagents were used as supplied and
chromatography solvents were distilled prior to use. Column
chromatography was performed on Silica Gel 60 (40–
4-Pentenyl 2,4,6-tri-O-benzyl-3-O-p-methoxybenzyl-ꢀ-D-
mannopyranoside (6)
To an ice-cooled solution of compound 5 (6.0 g, 16.3 mmol)
in DMF (100 mL) under argon, was added sodium hydride
(95%, 2.47 g, 97.8 mmol), and the mixture was stirred for
0.5 h. Benzyl bromide (8.7 mL, 72.9 mmol) was added
dropwise and the reaction was continued for 6 h at room
temperature. The reaction was cooled to 0°C and quenched
with MeOH (10 mL). The mixture was concentrated and the
resulting residue was partitioned between EtOAc (500 mL)
and 5% aq NaCl solution (2 × 300 mL). The organic phase
was dried over anhyd Na2SO4 and concentrated. Compound
6 (7.9 g, yield 76%) was obtained by column chromato-
graphy on silica gel (hexane–EtOAc, 19:1 v/v). [ꢀ]2D2 +33.2
1
60 M, E. Merck, Darmstadt). H NMR spectra were re-
corded on 300 MHz (Varian), 400 MHz (Varian), 500 MHz
(Varian), or 600 MHz (Varian) spectrometers. The first-order
proton chemical shifts (ꢃH) were referenced to either resid-
ual CHCl3 (ꢃH 7.24, CDCl3) or internal acetone (ꢃH 2.225,
D2O). HMQC-NMR spectra were recorded on Varian Unity
300, 400, 500, or 600 MHz NMR spectrometers. The
13C chemical shifts (ꢃC) were referenced to internal CDCl3
(ꢃC 77.00, CDCl3). Organic solutions were dried prior to
concentration under vacuum at <40°C (bath). Reverse-phase
chromatography was performed on a Waters 600 HPLC sys-
tem, using a Beckman semipreparative C-18 column (10 ×
250 mm, 5 ), and the products were detected with a Waters
1
(c 3.8, CDCl3). H NMR (CDCl3, 600 MHz) ꢃ: 7.36–6.83
(m, 19H, 3 × Bn + MBn), 5.76 (tdd, J = 6.6, 10.1, 16.9 Hz,
1H, CH=CH2), 4.95 (m, 2H, CH=CH2), 4.85 (d, J = 10.8 Hz,
1H, Bn), 4.81 (d, J = 1.9 Hz, 1H, H-1), 4.74 (d, J = 12.5 Hz,
1H, Bn), 4.69 (d, 1H, Bn), 4.63 (d, J = 12.1 Hz, 1H, Bn),
© 2002 NRC Canada

Yu et al.
1135
4.54 (d, J = 8.1 Hz, 2H, MBn), 4.52 (d, 1H, Bn), 4.88 (d,
1H, Bn), 3.93 (“t”, J = 9.3 Hz, 1H, H-4), 3.87 (dd, J =
3.1 Hz, 1H, H-3), 3.78–3.70 (m, 4H, H-6 + H-5 + H-2), 3.65
(td, J = 6.6, 9.7 Hz, 1H, OCH2CH2), 3.34 (td, 1H,
OCH2CH2), 2.04 (m, 2H, CH2CH=CH2), 1.60 (m, 2H,
OCH2CH2). 13C NMR (600 MHz, CDCl3, from HMQC) ꢃ:
137.8 (CH=CH2), 129.2–127.2 (3 × Bn + MBn), 113.8
(MBn), 114.7 (CH=CH2), 96.8 (C-1, JC1,H1 = 165.1 Hz),
79.7 (C-3), 74.9 (Bn), 74.9 (C-4), 74.7 (C-2), 73.2 (Bn),
72.4 (Bn), 71.8 (C-5), 71.7 (MBn), 69.2 (C-6), 66.8 (OCH2),
30.2 (CH2CH=CH2), 28.3 (OCH2CH2). HR-ES-MS calcd.
for C40H46O7Na+: 661.314124; found: 661.314477. Anal. calcd.
for C40H46O7: C 75.21, H 7.26; found: C 75.11, H 7.49.
5.0, 9.9, 11.4 Hz, 1H, H-2), 4.73 (d, J = 12.3 Hz, 1H, Bn),
4.44 (d, 1H, Bn), 4.43 (d, 1H, H-1), 3.62 (dq, J = 1.5,
6.4 Hz, 1H, H-5), 3.41 (m, 1H, H-4), 2.69 (m, 2H, CH2),
2.56 (ddd, J = 3.3, 13.6 Hz, 1H, H-3a), 2.05 (s, 3H, OAc),
1.50 (ddd, J = 2.8 Hz, 1H, H-3b), 1.25 (d, 3H, H-6), 1.24 (d,
J = 7.5 Hz, 3H, CH3). 13C NMR (CDCl3, 600 MHz) ꢃ: 120.8
(Bn), 84.4 (C-1), 76.5 (C-5), 74.2 (C-4), 70.7 (Bn), 66.4
(C-2), 32.9 (C-3), 23.1 (CH2), 20.8 (OAc), 16.8 (C-6), 6.2
(CH3). HR-ES-MS calcd. for C17H24O4SNa+: 347.129301;
found: 374.129420. Anal. calcd. for C17H24O4S: C 62.93, H
7.46; found: C 63.45, H 7.68. As both ꢀ and ꢂ anomers are
equally reactive in glycosylation reactions, 9ꢀ and 9ꢂ were
not separated.
Ethyl 2,4-di-O-benzyl-3,6-dideoxy-1-thio-ꢀ,ꢂ-D-xylo-
hexopyranoside (10)
4-Pentenyl 2,4,6-tri-O-benzyl-ꢀ-D-mannopyranoside (7)
Compound 6 (5.45 g, 8.53 mmol) and ceric ammonium
nitrate (11.7 g, 21.3 mmol) were stirred in a mixture of
acetonitrile (100 mL) and water (10 mL). After 45 min, the
mixture was concentrated. The residue was dissolved in di-
chloromethane (250 mL) and the organic solution was
washed with water (100 mL), 5% brine (100 mL), and dried
over Na2SO4. After concentration, the residue was purified
by column chromatography on silica gel (hexane–EtOAc,
8:1 v/v) to give compound 7 (3.2 g, yield 72%). [ꢀ]2D2 +16.2
To a solution of compound 9ꢀ,ꢂ (ꢀ/ꢂ (1:3), 200 mg,
0.62 mmol) in dry MeOH (20 mL) was added a catalytic
amount of MeONa. The mixture was stirred overnight at
room temperature. After neutralization with DOWEX 50W
(H+) resin, the organic solution was concentrated, and the re-
sulting residue was dissolved in anhyd DMF (10 mL) at
0°C; NaH (60% in mineral oil, 244 mg, 6.1 mmol) was then
added. After 5 min, benzyl bromide (0.37 mL, 3.1 mmol)
was added dropwise, and the reaction was continued for 2 h
at room temperature. The reaction was quenched with
MeOH (1 mL) and the mixture was diluted with EtOAc
(100 mL), washed with 5% brine (2 × 50 mL), dried over
Na2SO4, and concentrated. The pure 10 (ꢀ/ꢂ (1:3), 211 mg,
yield 92%) was obtained after chromatography on silica gel
(toluene–EtOAc, 19:1 v/v). Physical data were identical to
the literature (22).
1
(c 3.7, CHCl3), (lit. (33) value [ꢀ]2D2 +21). H NMR (CDCl3,
600 MHz) ꢃ: 7.36–7.21 (m, 15H, 3 × Bn), 5.76 (tdd, J = 6.6,
10.2, 17.0 Hz, 1H, CH=CH2), 4.95 (m, 2H, CH=CH2), 4.89
(d, J = 1.7 Hz, 1H, H-1), 4.83 (d, J = 11.0 Hz, 1H, Bn), 4.73
(d, J = 11.9 Hz, 1H, Bn), 4.65 (d, J = 12.1 Hz, 1H, Bn), 4.55
(d, 1H, Bn), 4.53 (d, 1H, Bn), 4.51 (d, 1H, Bn), 3.97 (ddd,
J = 3.7, 9.0, 9.0 Hz, 1H, H-3), 3.77–3.66 (m, 6H, H-5 + H-6
+ H-2 + OCHaHbCH2 + H-4), 3.37 (td, J = 6.4, 9.7 Hz, 1H,
OCHaHbCH2), 2.28 (d, 1H, 3-OH), 2.06 (m, 2H,
CH2CH=CH2), 1.62 (m, 2H, OCH2CH2). HR-ES-MS calcd.
for C32H38O6Na+: 541.256609; found: 541.256245. Anal. calcd.
for C32H38O6: C 74.11, H 7.39; found: C 74.12, H 7.56.
Methyl 3,6-dideoxy-ꢀ-D-ribo-hexopyranoside (12)
To a refluxing solution of 3,6-dibromosugar 11 (23)
(2.55 g, 8.0 mmol) in dry toluene (150 mL) was added
dropwise a solution of tri-n-butyltin hydride (6.5 mL,
24.2 mmol) and azobis(cyclohexylcarbonitrile) (0.2 g,
818 mol) in dry toluene (50 mL) under argon. After 1 h,
the mixture was concentrated. The residue was purified by
column chromatography on silica gel (toluene–EtOAc, 1:9
v/v) to give compound 12 (1.27 g, 98%). Physical data were
identical to the literature (23).
Ethyl 2-O-acetyl-4-O-benzyl-3,6-dideoxy-1-thio-ꢀ-D-xylo-
hexopyranoside (9ꢀ) and ethyl 2-O-acetyl-4-O-benzyl-
3,6-dideoxy-1-thio- ꢂ-D-xylo-hexopyranoside (9ꢂ)
A mixture of 1,2-di-O-acetyl-4-O-benzyl-3,6-dideoxy-
ꢀ, ꢂ-D-xylo-hexopyranose 8 (ꢀ/ꢂ (1:3), 99 mg, 0.31 mmol),
ethanethiol (34 L, 0.41 mmol) and 4 Å molecular sieves in
anhyd CH2Cl2 (3 mL) was cooled to 0°C under argon, and
BF3·Et2O (59 L, 0.47 mmol) was added dropwise. The
mixture was stirred at room temperature for 30 min and
quenched with Et3N (1 mL). The solvent was evaporated and
the residue was purified by silica gel (hexane–EtOAc, 9:1
v/v), to give the ꢀ-anomer 9ꢀ (23 mg, yield 23%) and ꢂ-
anomer 9ꢂ (72 mg, yield 72%). Data for 9ꢀ: [ꢀ]2D2 +141.6
1,2,4-Tri-O-acetyl-3,6-dideoxy-ꢀ,ꢂ-D-ribo-hexopyranose (14)
To a mixture of compound 13 () (1.20 g, 4.88 mmol) in
acetic anhydride (35 mL) was added a solution of conc.
H2SO4 (95%, 90 L). After 1 h, the reaction was quenched
with sat. NaHCO3 solution (50 mL) and extracted with di-
chloromethane (300 mL). The organic layer was washed
with H2O (200 mL) and dried over Na2SO4. The solvent was
evaporated and the residue was purified by silica gel
(hexane–EtOAc, 4:1 v/v), to give compound 14 (ꢀ/ꢂ (4:1),
1
(c 3.1, CHCl3). H NMR (CDCl3, 300 MHz) ꢃ: 7.37–7.25
(m, 5H, Bn), 5.54 (d, J = 5.0 Hz, 1H, H-1), 5.29 (d>t>, J =
12.2 Hz, 1H, H-2), 4.71 (d, J = 12.0 Hz, 1H, Bn), 4.44 (d,
1H, Bn), 4.23 (dq, J = 1.8, 6.5 Hz, 1H, H-5), 3.47 (m, 1H,
H-4), 2.55 (m, 2H, CH2), 2.19 (ddd, J = 1.4, 13.4 Hz, 1H,
H-3a), 2.05 (s, 3H, OAc), 1.81 (ddd, J = 2.7 Hz, 1H, H-3b),
1.25 (t, J = 7.4 Hz, 3H, CH3), 1.20 (d, 3H, H-6). HR-ES-MS
calcd. for C17H24O4SNa+: 347.129301; found: 374.129515.
Anal. calcd. for C17H24O4S: C 62.93, H 7.46; found: C 63.23,
1
1.14 mg, yield 85%). H NMR (CDCl3, 300 MHz) for
ꢀ-anomer ꢃ: 6.15 (d, J = 3.4 Hz, 1H, H-1), 4.97 (ddd, J =
5.0, 12.5 Hz, 1H, H-2), 4.60 (ddd, J = 4.8, 9.8, 11.4 Hz, 1H,
H-4), 3.84 (dq, J = 6.1 Hz, 1H, H-5), 2.28 (d>t>, J =
12.2 Hz, H-3a), 2.14 (s, 3H, OAc), 2.05 (s, 3H, OAc), 1.95
(s, 3H, OAc), 1.88 (d>t>, 1H, H-3b), 1.15 (d, 3H, H-6);
ꢂ-anomer ꢃ: 5.65 (d, J = 8.2 Hz, 1H, H-1), 4.97 (ddd, J =
5.2, 11.4 Hz, 1H, H-2), 4.60 (ddd, J = 4.8, 9., 11.0 Hz, 1H,
1
H 7.72. Data for 9ꢂ: [ꢀ]2D2 –77.8 (c 4.1, CHCl3). H NMR
(CDCl3, 600 MHz) ꢃ: 7.35–7.25 (m, 5H, Bn), 5.07 (ddd, J =
© 2002 NRC Canada

1136
Can. J. Chem. Vol. 80, 2002
H-4), 3.67 (dq, J = 6.1 Hz, 1H, H-5), 2.57 (d>t>, J = 12.3 Hz,
H-3a), 2.09 (s, 3H, OAc), 2.04 (s, 3H, OAc), 2.01 (s, 3H,
OAc), 1.59 (d>t>, 1H, H-3b), 1.21 (d, 3H, H-6). HR-ES-
MS calcd. for C12H18O7Na+: 297.09447; found: 297.09491.
Anal. calcd. for C12H18O7: C 52.55, H 6.62; found: C 52.39,
H 6.49.
9.2 Hz, 1H, H-5), 3.73 (d>t>, J = 4.6, 12.0 Hz, 1H, H-2),
3.05 (overlapped, 1H, H-4), 2.71 (overlapped, 2H, SCH2),
2.30 (m, 1H, H-3a), 1.74 (d>t>, J = 11.7 Hz, H-3b), 1.29
(overlapped, 3H, CH2CH3), 1.22 (d, 3H, H-6). HR-ES-MS
calcd. for C22H28O3SNa+: 395.165687; found: 395.165698.
Anal. calcd. for C22H28O3S: C 70.93, H 7.58; found: C 70.80,
H 7.60.
Ethyl 2,4-di-O-acetyl-3,6-dideoxy-1-thio-ꢀ,ꢂ-D-ribo-
hexopyranoside (15)
Ethyl 1-thio-ꢂ-D-mannopyranoside (18)
A mixture of 14 (890 mg, 3.24 mmol) and ethanethiol
(360 L, 4.86 mmol) in anhydrous CH2Cl2 (20 mL) was
cooled to 0°C under argon, BF3·Et2O (617 L, 4.86 mmol)
was added dropwise, and the mixture was stirred at room
temperature for 18 h. The reaction was quenched with Et3N
(1 mL) and the solvent was evaporated. The residue was pu-
rified by silica gel chromatography (hexane–EtOAc, 9:1 v/v)
to yield compound 15 as an inseparable ꢀ/ꢂ mixture (ꢀ/ꢂ
To a solution of 2,3,4,6-tetra-O-acetyl-1-S-acetyl-1-thio-ꢂ-
D-mannopyranose 17 (28) (4.6 g, 11.3 mmole) in dry MeOH
(50 mL) under argon, was added a solution of NaOMe–
MeOH (21 mL, 3.5 M), and the mixture was stirred for 2 h.
Ethyl iodide (2 mL, 25.0 mmol) was added dropwise and the
reaction was continued under argon for 2 h at room tempera-
ture. The mixture was neutralized with Dowex 50W (H+)
resin and concentrated. Compound 18 (2.43 g, 96%) was ob-
tained by reverse-phase chromatography using a gradient of
MeOH–H2O as eluent (0 J 20%). [ꢀ]2D2 –93.3 (c 7.3,
1
(1:3), 671 mg, yield 75%). H NMR (CDCl3, 300 MHz) for
ꢂ-anomer ꢃ: 4.83 (ddd, J = 5.0, 9.8, 11.2 Hz, 1H, H-2), 4.55
(ddd, J = 4.7, 9.5, 11.5 Hz, 1H, H-4), 4.36 (d, 1H, H-1), 3.45
(dq, J = 6.2 Hz, 1H, H-5), 2.65 (m, 2H, SCH2), 2.52 (d>t>,
J = 9.4 Hz, H-3a), 2.04 (s, 3H, OAc), 2.02 (s, 3H, OAc),
1.52 (d>t>, 1H, H-3b), 1.23 (t, J = 7.5 Hz, 3H, CH2CH3),
1.20 (d, 3H, H-6); ꢀ-anomer ꢃ: 5.48 (d, J = 5.2 Hz, 1H,
H-1), 4.97 (d>t>, J = 5.0, 12.3 Hz, 1H, H-2), 4.55 (ddd, J =
4.8, 9.7, 11.0 Hz, 1H, H-4), 4.11 (dq, J = 6.2 Hz, 1H, H-5),
2.54 (m, 2H, SCH2), 2.20 (d>t>, J = 11.8 Hz, H-3a), 2.02 (s,
6H, 2 × OAc), 1.80 (d>t>, 1H, H-3b), 1.24 (t, J = 7.4 Hz, 3H,
CH2CH3), 1.14 (d, 3H, H-6). HR-ES-MS calcd. for
C12H20O5SNa+: 299.092916; found: 299.093086. Anal. calcd.
for C12H20O5S: C 52.15, H 7.29; found: C 52.44, H 7.42.
1
MeOH). H NMR (D2O, 600 MHz) ꢃ: 4.88 (s, 1H, H-1),
4.04 (d, J = 3.5 Hz, 1H, H-2), 3.91 (dd, J = 12.3 Hz, 1H,
H-6a), 3.73 (dd, 1H, H-6b), 3.67 (dd, J = 9.5 Hz, 1H, H-3),
3.60 (“t”, J = 9.7 Hz, 1H, H-4), 3.43 (ddd, J = 2.4, 6.0 Hz,
1H, H-5), 2.76 (m, 2H, CH2), 1.38 (t, J = 7.3 Hz, 3H, CH3).
13C NMR (D2O, 600 MHz, from HMQC) ꢃ: 84.6 (C-1,
JC1,H1 = 154.3 Hz), 81.1 (C-5), 74.8 (C-3), 73.2 (C-2), 67.5
(C-4), 62.1 (C-6). HR-ES-MS calcd. for C8H16O5SNa+:
247.06107; found: 247.06091. Anal. calcd. for C8H16O5S:
C 42.84, H 7.19; found: C 42.81, H 7.19.
Ethyl 2,6-di-O-benzoyl-1-thio-ꢂ-D-mannopyranoside (19)
and ethyl 2,4-di-O-benzoyl-1-thio-ꢂ-D-mannopyranoside
(20)
Ethyl 2,4-di-O-benzyl-3,6-dideoxy-1-thio-ꢀ,ꢂ-D-ribo-
hexopyranoside (16)
A suspension of compound 18 (1.2 g, 1.02 mmol),
trimethyl orthobenzoate (3.8 mL, 5.3 mmol), and a catalytic
amount of camphor sulfonic acid in CHCl3 (250 mL) was
evaporated down to 10 mL; this solution became almost
clear. TLC showed that there was still unreacted starting ma-
terial. CHCl3 (150 mL) was added to the solution again, and
the solution was again evaporated to a 10 mL volume. This
process was repeated until TLC indicated the complete con-
version of starting material. Triethylamine (3 mL) was
added, and the mixture of intermediate orthoesters was con-
centrated to a syrup. The syrup was treated with 90% acetic
acid – H2O (50 mL) for 30 min at 20°C, and the solution
was concentrated. After column chromatography on silica
gel (EtOAc–toluene, 20 J 50%) compound 20 (1.02 g,
44%) and compound 19 (0.99 g, 43%) were obtained. Data
for 20: [ꢀ]2D2 –93.6 (c 2.8, CHCl3). 1H NMR (CDCl3,
400 MHz) ꢃ: 8.13–7.43 (m, 10H, Bz), 5.76 (d, J = 3.7 Hz,
1H, H-2), 5.39 (“t”, J = 9.7 Hz, 1H, H-4), 4.92 (s, 1H, H-1),
4.19 (dd, J = 9.8 Hz, 1H, H-3), 3.85 (dd, J = 2.3, 12.2 Hz,
1H, H-6a), 3.78 (dd, J = 5.3, 12.2 Hz, 1H, H-6b), 3.73 (ddd,
1H, H-5), 2.76 (q, J = 7.5 Hz, 2H, CH2), 1.29 (t, 3H, CH3).
HR-ES-MS calcd. for C22H24O7SNa+: 455.114045; found:
455.114338. Anal. calcd. for C22H24O7S: C 61.10, H
5.59; found: C 61.11, H 5.43. Data for 19: [ꢀ]2D2 –78.5
To a solution of compound 15 (ꢀ/ꢂ (1:3), 253 mg,
0.92 mmol) in anhyd MeOH (4.5 mL) was added a catalytic
amount of NaOMe, and the reaction was continued for 2 h at
room temperature. The mixture was neutralized with
DOWEX 50W (H+) resin and the organic solvent was evapo-
rated. The residue was dissolved in anhyd DMF (9 mL) at
0°C under argon, NaH (60% in mineral oil, 368 mg, 9.2 mmol)
was added, and the mixture was stirred for 5 min. Benzyl
bromide (1.08 mL, 9.08 mmol) was added dropwise, and the
reaction was stirred for 2 h at room temperature. MeOH
(1 mL) was added to quench the reaction and the mixture
was diluted with EtOAc (100 mL). The organic solution was
washed with 5% brine (2 × 50 mL), dried over Na2SO4 and
concentrated. The pure compound 16 (ꢀ/ꢂ (1:3), 266 mg,
yield 78%) was obtained by chromatography on silica gel
1
(toluene–EtOAc, 19:1 v/v). H NMR (CDCl3, 600 MHz) for
ꢂ-anomer ꢃ: 7.36–7.26 (m, 10H, 2 × Bn), 4.68 (d, J =
11.5 Hz, 1H, Bn), 4.59 (d, J = 11.5 Hz, 1H, Bn), 4.49 (d,
1H, Bn), 4.43 (d, Bn), 4.41 (d, J = 9.3 Hz, 1H, H-1), 3.35
(dq, J = 6.0, 9.0 Hz, 1H, H-5), 3.28 (ddd, J = 9.3, 11.2 Hz,
1H, H-2), 3.08 (overlapped, 1H, H-4), 2.71 (overlapped, 2H,
SCH2), 2.60 (m, 1H, H-3a), 1.48 (d>t>, J = 11.2 Hz, H-3b),
1.29 (overlapped, 3H, CH2CH3), 1.28 (d, 3H, H-6); ꢀ-anomer
ꢃ: 7.36–7.26 (m, 10H, 2 × Bn), 5.33 (d, J = 5.0 Hz, 1H, H-1),
4.65 (d, J = 10.6 Hz, 1H, Bn), 4.61 (d, J = 11.5 Hz, 1H, Bn),
4.49 (d, 1H, Bn), 4.42 (d, 1H, Bn), 4.06 (dq, J = 6.0 Hz,
1
(c 9.3, CHCl3). H NMR (CDCl3, 600 MHz) ꢃ: 8.12–7.30
(m, 10H, Bz), 5.64 (dd, J = 0.92, 3.3 Hz, 1H, H-2), 4.86 (d,
1H, H-1), 4.80 (dd, J = 4.6, 12.1 Hz, 1H, H-6a), 4.62 (dd,
© 2002 NRC Canada

Yu et al.
1137
J = 2.2 Hz, 1H, H-6b), 3.93 (d>t>, J = 3.5, 9.3 Hz, 1H, H-3),
3.83 (d>t>, J = 3.3, 9.5 Hz, 1H, H-4), 3.67 (ddd, 1H, H-5),
2.96 (d, 1H, 4-OH), 2.73 (m, 2H, CH2), 2.65 (d, 1H, 3-OH),
1.28 (t, J = 7.5 Hz, 3H, CH3). HR-ES-MS calcd. for
C22H24O7SNa+: 455.114045; found: 455.114045. Anal. calcd.
for C22H24O7S: C 61.10, H 5.59; found: C 61.42, H, 5.57.
395.165827. Anal. calcd. for C22H28O3S: C 70.93, H 7.58;
found: C 70.78, H 7.45.
4-Pentenyl 2,4-di-O-benzyl-3,6-dideoxy-ꢀ-D-xylo-hexo-
pyranosyl-(1J3)-2,4,6-tri-O-benzyl-ꢀ-D-mannopyrano-
side (24ꢀ) and 4-pentenyl 2,4-di-O-benzyl-3,6-dideoxy-ꢂ-
D-xylo-hexopyranosyl-(1J3)-2,4,6-tri-O-benzyl-ꢀ-D-
mannopyranoside (24ꢂ)
Ethyl 2,4-di-O-benzoyl-3,6-di-O-(imidazolylthio-
carbonyl)-1-thio-ꢂ-D-mannopyranoside (21)
To a mixture of 10 (1.18 g, 3.17 mmol), 7 (1.13 g,
2.17 mmol), 2,6-di-tert-butyl-4-methylpyridine (0.87 g, 4.24 mmol),
and 4 Å molecular sieves in anhyd Et2O (20 mL) at 0°C un-
der argon, methyl trifluoromethanesulfonate (737 L, 6.51 mmol)
was added dropwise. The mixture was stirred at room tem-
perature for 6 h and then quenched with Et3N (3 mL). The
molecular sieves were removed by filtration and the solvent
was evaporated. The resulting residue was purified by col-
umn chromatography on silica gel (hexane–EtOAc, 24:1 v/v),
to give the ꢀ-anomer 24ꢀ (1.45 g, yield 80%) and ꢂ-anomer
24ꢂ (34 mg, yield 2%). Data for 24ꢀ: [ꢀ]2D2 +38.8 (c 4.0,
A mixture of compound 20 (230 mg, 0.53 mmol) and 1,1>-
thiocarbonyldimidazole (368 mg, 2.07 mmol) in anhydrous
toluene (4.0 mL) was refluxed for 4 h. The solvent was re-
moved under reduced pressure and the residue was purified
by column chromatography on silica gel (toluene–EtOAc,
1:1 v/v) to afford 21 (264 mg, 76%). [ꢀ]2D2 –83.9 (c 1.3,
1
CHCl3). H NMR (CDCl3, 400 MHz) ꢃ: 8.40–6.83 (m, 16H,
Bz + Im), 6.14 (dd, J = 3.4, 9.9 Hz, 1H, H-3), 6.11 (d, 1H,
H-2), 5.99 (“t”, J = 9.9 Hz, 1H, H-4), 5.12 (s, 1H, H-1), 5.10
(dd, J = 2.5, 12.1 Hz, 1H, H-6a), 4.79 (dd, J = 5.1 Hz, 1H,
H-6b), 4.31 (ddd, 1H, H-5), 2.80 (q, J = 7.5 Hz, 2H, CH2),
1.31 (t, 3H, CH3). HR-ES-MS calcd. for C30H29N4O7Sꢄ3:
653.119840; found: 653.119769. Anal. calcd. for
C30H28N4O7S3: C 55.20, H 4.32, N 8.58; found: C 55.33,
H 4.23, N 8.41.
1
CHCl3). H NMR (CDCl3, 600 MHz) ꢃ: 7.34–7.12 (m, 25H,
5 × Bn), 5.78 (tdd, J = 6.6, 10.1, 16.9 Hz, 1H, CH=CH2),
5.14 (d, J = 3.3 Hz, 1H, H-1>), 5.07 (d, J = 11.4 Hz, 1H,
Bn), 4.95 (m, 2H, CH=CH2), 4.89 (d, J = 1.8 Hz, 1H, H-1),
4.73 (d, J = 12.1 Hz, 1H, Bn), 4.60 (d, J = 12.1 Hz, 2H, Bn),
4.49 (d, 1H, Bn), 4.48 (d, J = 12.1 Hz, 1H, Bn), 4.44 (d, 1H,
Bn), 4.43 (d, J = 12.5 Hz, 1H, Bn), 4.35 (d, 1H, Bn), 4.30
(d, 1H, Bn), 4.15 (dd, J = 9.3 Hz, 1H, H-3), 3.97 (“t”, J =
9.5 Hz, 1H, H-4), 3.84 (m, 1H, H-5>), 3.80–3.76 (m, 2H,
H-2> + H-5), 3.75 (dd, J = 3.1 Hz, 1H, H-2), 3.71 (m, 2H,
H-6), 3.67 (m, 1H, OCHaHbCH2), 3.38 (td, J = 6.4, 9.5 Hz,
1H, OCHaHbCH2), 3.26 (br s, 1H, H-4>), 2.10–2.03 (m, 3H,
CH2CH=CH2 + H-3>a), 1.88 (d>t>, J = 2.6, 12.8 Hz, 1H,
H-3>b), 1.65 (tt, J = 7.0, 7.0 Hz, 2H, OCH2CH2), 1.04 (d,
J = 6.6 Hz, 3H, H-6>). 13C NMR (CDCl3, 600 MHz, from
HMQC) ꢃ: 138.0 (CH=CH2), 128.2–126.9 (5 × Bn), 114.6
Ethyl 2,4-di-O-benzoyl–3,6-dideoxy-1-thio-ꢂ-D-arabino-
hexopyranoside (22)
To a refluxing solution of compound 21 (700 mg,
1.07 mmol) in dry toluene (8.0 mL) was added dropwise a
solution of tri-n-butyltin hydride (0.8 mL, 3.0 mmol) and
azobis(cyclohexylcarbonitrile) (90 mg, 368 mol) in dry to-
luene (5.0 mL) under argon. After 6 h, the mixture was con-
centrated. Chromatography of the resulting residue on silica
gel (toluene–EtOAc, 19:1 v/v) gave compound 22 (195 mg,
45%). Physical data were similar to those in the literature (33).
(CH=CH2), 98.8 (C-1, JC1,H1 = 169.3 Hz), 97.0 (C-1>, JC1>,H1>
=
Ethyl 2,4-di-O-benzyl–3,6-dideoxy-1-thio-ꢂ-D-arabino-
hexopyranoside (23)
169.3 Hz), 78.4 (C-3), 77.9 (C-2), 75.5 (C-4>), 74.8 (C-4),
74.3 (Bn), 73.2 (2 × Bn), 71.9 (C-5), 71.6 (Bn), 70.9–70.7
(2 × Bn), 70.7 (C-2>), 69.3 (C-6), 66.9 (OCH2), 66.3 (C-5>),
30.2 (CH2CH=CH2), 28.5 (OCH2CH2), 27.1 (C-3>), 16.4
(C-6>). HR-ES-MS calcd. for C52H60O9Na+: 851.413504; found:
851.413319. Anal. calcd. for C52H60O9: C 75.34, H 7.29;
found: C 74.98, H 7.41. Data for 24ꢂ: [ꢀ]2D2 +21.4 (c 2.8,
To a solution of compound 21 (195 mg, 0.49 mmol) in
dry MeOH (5 mL) was added a catalytic amount of MeONa.
The mixture was stirred overnight at room temperature. Af-
ter neutralization with DOWEX 50W (H+) resin, the reaction
was concentrated. The residue was dissolved in anhyd DMF
(9 mL) at 0°C under argon and NaH (60% in mineral oil,
180 mg, 4.5 mmol) was then added. After 5 min, benzyl bro-
mide (0.53 mL, 4.5 mmol) was added dropwise, and the re-
action was continued for 2 h at room temperature. MeOH
(1 mL) was added to quench the reaction, and the mixture
was diluted with EtOAc (100 mL), washed with 5% brine
(2 × 50 mL), dried over Na2SO4 and concentrated. Pure 23
(172 mg, yield 95%) was obtained by chromatography on
silica gel (toluene–EtOAc, 9:1 v/v). [ꢀ]2D2 –10.0 (c 1.3,
1
CHCl3). H NMR (CDCl3, 600 MHz) ꢃ: 7.34–7.15 (m, 25H,
5 × Bn), 5.75 (tdd, J = 6.6, 10.3, 17.0 Hz, 1H, CH=CH2),
5.00 (d, J = 10.4 Hz, 1H, Bn), 4.93 (m, 2H, CH=CH2), 4.81
(d, J = 2.2 Hz, 1H, H-1), 4.77 (d, J = 12.1 Hz, 1H, Bn), 4.73
(d, J = 12.1 Hz, 2H, Bn), 4.66 (d, 1H, Bn), 4.64 (d, J =
11.7 Hz, 1H, Bn), 4.58–4.53 (m, 5H, H-1> + 3 × Bn), 4.42
(d, 1H, Bn), 4.38 (d, J = 12.1 Hz, 1H, Bn), 4.32 (dd, J = 3.1,
8.6 Hz, 1H, H-3), 3.92 (“t”, J = 9.0 Hz, 1H, H-4), 3.79–3.70
(m, 4H, H-2 + H-5 + H-6), 3.63 (m, 2H, OCHaHbCH2 + H-
2>), 3.58 (dq, J = 1.5, 6.4 Hz, 1H, H-5>), 3.36 (m, 1H, H-4>),
3.34 (td, J = 6.6, 9.9 Hz, 1H, OCHaHbCH2), 2.36 (ddd, J =
3.1, 4.8, 13.7 Hz, 1H, H-3>a), 2.03 (m, 2H, CH2CH=CH2),
1.60 (tt, J = 6.8, 7.3 Hz, 2H, OCH2CH2)), 1.48 (ddd, J = 2.8,
11.5 Hz, 1H, H-3>b), 1.19 (d, 3H, H-6>). HR-ES-MS calcd.
for C52H60O9Na+: 851.413504; found: 851.413576. Anal.
calcd. for C52H60O9: C 75.34, H 7.29; found: C 74.89,
H 7.44.
1
CHCl3). H NMR (CDCl3, 600 MHz) ꢃ: 7.35–7.25 (m, 10H,
Bn), 4.58 (s, 1H, H-1), 4.56 (overlapped, 2H, Bn), 4.49 (d,
J = 11.5 Hz, 1H, Bn), 4.44 (d, 1H, Bn), 3.71 (m, 1H, H-2),
3.45 (ddd, J = 4.4, 9.2, 11.2 Hz, 1H, H-4), 3.37 (qd, J =
6.1 Hz, 1H, H-5), 2.67 (q, J = 7.3 Hz, 2H, CH2), 2.38 (d>t>,
J = 3.7 Hz, 13.6 Hz, 1H, H-3a), 1.39 (ddd, J = 2.8 Hz, 1H,
H-3b), 13.3 (d, 3H, H-6), 1.26 (t, J = 7.5 Hz, 1H, CH3). HR-
ES-MS calcd. for C22H28O3Na+: 395.165687; found:
© 2002 NRC Canada

1138
Can. J. Chem. Vol. 80, 2002
(ddd, J = 3.1, 7.3 Hz, 12.8 Hz, 2H, OCHaHbCH2), 2.21 (m,
1H, H-3>a), 2.07 (m, 2H, CH2CH=CH2), 1.92 (d>t>, J = 1.5,
11.5 Hz, 1H, H-3>b), 1.63 (m, 2H, OCH2CH2), 1.25 (d, J =
7.0 Hz, 3H, H-6>). 13C NMR (600 MHz, CDCl3, from
HMQC) ꢃ: 138.1 (CH=CH2), 128.2–126.2 (5 × Bn), 114.8
4-Pentenyl 2,4-di-O-benzyl-3,6-dideoxy-ꢀ,ꢂ-D-ribo-
hexopyranosyl-(1J3)-2,4,6-tri-O-benzyl-ꢀ-D-mannopy-
ranoside (25)
To a mixture of 16 (94 mg, 0.25 mmol), 7 (196 mg,
0.38 mmol), 2,6-di-tert-butyl-4-methylpyridine (103 mg,
0.50 mmol) in anhyd Et2O (5 mL) at 0°C under argon,
methyl trifluoromethanesulfonate (87 L, 0.77 mmol) was
added dropwise. The mixture was stirred at room tempera-
ture for 7.5 h and then quenched with Et3N (1 mL). The
mixture was concentrated and the resulting residue was puri-
fied by column chromatography on silica gel (toluene–
EtOAc, 49:1 v/v) to give compound 25 as an inseparable
mixture of anomers (ꢀ/ꢂ (3:2), 167 mg, yield 80%). 1H NMR
(CDCl3, 600 MHz) for ꢀ-isomer ꢃ: 7.42–7.12 (m, 25H, 5 ×
Bn), 5.77 (m, 1H, CH=CH2), 5.11 (d, J = 3.3 Hz, 1H, H-1>),
5.04 (d, J = 11.5 Hz, 1H, Bn), 4.97 (m, 2H, CH=CH2), 4.93
(d, J = 11.0 Hz, 1H, Bn), 4.86 (d, J = 2.0 Hz, 1H, H-1), 4.76
(d, J = 12.2 Hz, 1H, Bn), 4.65–4.58 (overlapped, 3H, 3 ×
Bn), 4.51 4.42 (overlapped, 3H, 4 × Bn), 4.18 (dd, J = 3.1,
9.5 Hz, 1H, H-3), 4.00 (“t”, J = 9.7 Hz, 1H, H-4), 3.84 (dq,
J = 6.2, 9.1 Hz, 1H, H-5> ), 3.80–3.64 (m, 4H, H-2 + H-5 +
H-6a + OCHaHbCH2), 3.43 (d>t>, J = 3.3, 11.7 Hz, 1H, H-2>),
3.36 (m, 2H, H-6b + OCHaHbCH2), 3.04 (ddd, J = 4.4,
11.2 Hz, 1H, H-4>), 2.31 (d>t>, J = 11.5 Hz, 1H, H-3>a), 2.06
(m, 2H, CH2CH=CH2), 1.92 (d>t>, 1H, H-3>b), 1.63 (m, 2H,
OCH2CH2), 1.17 (d, 3H, H-6>). Selected data for ꢂ-anomer
ꢃ: 4.82 (d, J = 2.2 Hz, 1H, H-1), 4.54 (d, J = 7.5 Hz, 1H,
H-1>), 4.29 (dd, J = 3.1, 8.6 Hz, 1H, H-3), 3.94 (“t”, J =
9.0 Hz, 1H, H-4), 3.80–3.64 (m, 4H, H-2 + H-5 + H-6a +
OCHaHbCH2), 3.38–3.34 (m, 3H, H-5> + H-6b + OCHaHbCH2),
3.28 (ddd, J = 5.0, 11.9 Hz, 1H, H-2>), 3.08 (ddd, J = 4.4,
9.0, 11.0 Hz, 1H, H-4>), 2.50 (d>t>, J = 12.5 Hz, 1H, H-3>a),
2.06 (m, 2H, CH2CH=CH2), 1.63 (m, 2H, OCH2CH2), 1.50
(d>t>, 1H, H-3>b), 1.24 (d, J = 6.1 Hz, 3H, H-6>). HR-ES-MS
calcd. for C52H60O9Na+: 851.413504; found: 851.412747.
Anal. calcd. for C52H60O9: C 75.34, H 7.28; found: C 75.30,
H 7.30.
(CH=CH2), 98.6 (C-1>, JC1>,H1> = 167.9 Hz), 97.6 (C-1, JC1,H1
=
167.3 Hz), 77.9 (C-5), 77.4 (C-3), 75.6 (C-2>), 75.3 (C-4>),
75.2 (C-4), 74.4 (Bn), 73.2 (Bn), 72.4 (Bn), 71.6 (C-2), 70.8
(Bn), 70.6 (Bn), 69.0 (C-6), 68.4 (C-5>), 66.8 (OCH2), 30.0
(CH2CH=CH2), 29.2 (C-3>), 28.4 (OCH2CH2), 17.8 (C-6>).
HR-ES-MS calcd. for C52H60O9Na+: 851.413504; found:
851.413354. Anal. calcd. for C52H60O9: C 75.34, H 7.28;
found: C 74.94, H 7.29.
4-Pentenyl 3,6-dideoxy-ꢀ-D-xylo-hexopyranosyl-(1J3)-ꢀ-
D-mannopyranoside (27)
Redistilled liquid ammonia (50 mL) was collected in a
flask with the help of a dry ice – acetone condenser, sodium
(83 mg) was added, a dark blue solution was obtained and
the mixture was cooled to –78°C. A solution of compound
24ꢀ (200 mg, 0.24 mmol) and anhyd MeOH (52 L,
1.29 mmol) in anhyd THF (20 mL) was added dropwise to a
blue mixture during the course of 1 h. After another 1.5 h,
the reaction was then quenched with MeOH (2 mL), the am-
monia was evaporated to dryness. The residue was dissolved
in MeOH and the mixture was neutralized to pH 7 by addi-
tion of 25% AcOH in H2O. After concentration, the residue
was purified by reverse-phase chromatography using a gradi-
ent of MeOH–H2O (0 J 50%) as eluent to afford 27 (91 mg,
1
100%). [ꢀ]2D2 +70.0 (c 1.2, H2O). H NMR (D2O, 600 MHz)
ꢃ: 5.92 (tdd, J = 6.6, 10.3, 17.0 Hz, 1H, CH=CH2), 5.10 (d,
J = 3.7 Hz, 1H, H-1>), 5.10 (overlapped, 1H, CH=CHaHb),
5.03 (m, 1H, CH=CHaHb), 4.85 (d, J = 1.7 Hz, 1H, H-1),
4.12 (dq, J = 1.3, 6.6 Hz, 1H, H-5>), 4.05 (dd, J = 1.8 Hz,
3.1 Hz, 1H, H-2), 4.01 (d>t>, J = 4.0, 12.5 Hz, 1H, H-2>),
3.90–3.87 (m, 3H, H-3 + H-6a + H-4>), 3.84 (“t”, J =
9.7 Hz, 1H, H-4), 3.77 (m, 2H, OCHaHbCH2 + H-6b), 3.70
(ddd, J = 2.2, 5.7, 9.5 Hz, 1H, H-5), 3.56 (d>t>, J = 6.1,
12.1 Hz, 1H, OCHaHbCH2), 2.16 (m, 2H, CH2CH=CH2),
2.06 (d>t>, J = 2.9, 13.0 Hz, 1H, H-3>a), 1.98 (d>t>, J =
4.6 Hz, 1H, H-3>b) 1.74 (m, 2H, OCH2CH2), 1.16 (d, 3H,
H-6>). 13C NMR (D2O, 600 MHz, from HMQC) ꢃ: 138.7
4-Pentenyl 2,4-di-O-benzyl-3,6-dideoxy-ꢀ-D-arabino-
hexopyranosyl-(1J3)-2,4,6-tri-O-benzyl-ꢀ-D-mannopy-
ranoside (26)
To a mixture of 23 (50 mg, 0.13 mmol), 7 (77 mg,
0.15 mmol), 2,6-di-tert-butyl-4-methylpyridine (55 mg, 0.27 mmol),
and 4 Å molecular sieves in anhyd Et2O (2 mL) at 0°C
under argon, methyl trifluoromethanesulfonate (46 L,
0.41 mmol) was added dropwise. The mixture was stirred at
room temperature for 2 h and then quenched with Et3N
(1 mL). The mixture was concentrated and the resulting resi-
due was purified by column chromatography on silica gel
(toluene–EtOAc, 49:1 v/v) to give compound 26 (78 mg,
(CH=CH2), 116.7 (CH=CH2), 101.2 (C-1>, JC1>,H1>
=
169.8 Hz), 100.3 (C-1, JC1,H1 = 171.9 Hz), 79.2 (C-3), 74.0
(C-5), 71.2 (C-2), 69.0 (C-4>), 68.1 (OCH2), 65.5 (C-5>),
66.3 (C-4), 65.0 (C-2>), 61.9 (C-6), 33.4 (C-3>), 30.2
(CH2CH=CH2), 28.6 (OCH2CH2), 16.0 (C-6>). HR-ES-MS
calcd. for C17H30O9Na+: 401.178753; found: 401.178537.
4-Pentenyl 3,6-dideoxy-ꢀ-D-ribo-hexopyranosyl-(1J3)-ꢀ-
D-mannopyranoside (28ꢀ) and 4-pentenyl 3,6-dideoxy-ꢂ-
D-ribo-hexopyranosyl-(1J3)-ꢀ-D-mannopyranoside (28ꢂ)
Compound 25 (74 mg, 89.3 mol) was deprotected as de-
scribed for 24ꢀ to afford 28ꢀ (16 mg, yield 47%) and 28ꢂ
(11 mg, yield 33%). Data for 28ꢀ: [ꢀ]D22 +86.0 (c 1.0, H2O).
1H NMR (CD3OD, 600 MHz) ꢃ: 5.84 (ddt, J = 6.8, 10.3,
17.0 Hz, 1H, CH=CH2), 5.02 (m, 1H, CH=CHaHb), 4.97 (d,
J = 3.7 Hz, 1H, H-1>), 4.95 (m, 1H, CH=CHaHb), 4.72 (d,
J = 1.7 Hz, 1H, H-1), 3.94 (dd, J = 4.1 Hz, 1H, H-2), 3.83
(“t”, J = 9.5 Hz, 1H, H-4), 3.80 (m, 2H, H-6a + H-3), 3.77–
3.70 (m, 3H, OCHaHbCH2 + H-5> + H-6b), 3.63 (d>t>,
1
yield 70%). [ꢀ]2D2 +40.0 (c 1.5, CHCl3). H NMR (CDCl3,
600 MHz) ꢃ: 7.40–7.12 (m, 25H, 5 × Bn), 5.70 (m, 1H,
CH=CH2), 5.06 (s, 1H, H-1>), 4.95 (m, 2H, CH=CH2), 4.82
(s, 1H, H-1), 4.76 (d, J = 11.9 Hz, 1H, Bn), 4.70 (d, J =
12.3 Hz, 1H, Bn), 4.66 (d, 1H, Bn), 4.64 (d, J = 12.6 Hz,
1H, Bn), 4.56 (d, J = 11.5 Hz, 1H, Bn), 4.50 (d, 1H, Bn),
4.48 (d, 1H, Bn), 4.46 (d, 1H, Bn), 4.34 (d, J = 12.1 Hz, 1H,
Bn), 4.23 (d, 1H, Bn), 4.18 (dd, J = 2.8, 9.7 Hz, 1H, H-3),
3.76 (“t”, J = 9.7 Hz, 1H, H-4), 3.86 (m, 1H, H-5>), 3.76–
3.70 (m, 3H, H-2 + H-5 + H-6a), 3.66 (m, 2H, H-6b +
OCHaHbCH2), 3.61 (m, 1H, H-2>), 3.45 (m, 1H, H-4>), 3.36
© 2002 NRC Canada

Yu et al.
1139
J = 4.0, 12.1 Hz, 1H, H-2>), 3.56 (ddd, J = 2.4, 5.7 Hz, 1H,
H-5), 3.44 (dd, J = 6.4, 9.7 Hz, 1H, OCHaHbCH2), 2.27
(ddd, J = 4.6, 9.3, 11.4 Hz, 1H, H-4>), 2.15 (m, 2H,
CH2CH=CH2), 1.92 (d>t>, J = 11.4 Hz, 1H, H-3>a), 1.81
(d>t>, 1H, H-3>b), 1.69 (m, 2H, OCH2CH2), 1.18 (d, J =
6.2 Hz, 3H, H-6>). 13C NMR (CD3OD, 600 MHz, from
HMQC) ꢃ: 139.3 (CH=CH2), 115.1 (CH=CH2), 101.4 (C-1>,
JC1>,H1> = 168.3 Hz), 101.0 (C-1, JC1,H1 = 170.8 Hz), 80.6
(C-3), 74.5 (C-5), 71.9 (C-2), 71.5 (C-4>), 70.1 (C-5>), 69.0
(C-2>), 67.7 (OCH2), 67.4 (C-4), 62.5 (C-6), 37.0 (C-3>),
31.2 (CH2CH=CH2), 29.6 (OCH2CH2), 17.6 (C-6>). HR-ES-
MS calcd. for C17H30O9Na+: 401.178753; found: 401.178571.
1H, H-1), 4.12 (dq, J = 1.3, 6.6 Hz, 1H, H-5>), 4.05 (dd, J =
3.1 Hz, 1H, H-2), 4.01 (ddd, J = 4.8, 12.5 Hz, 1H, H-2>),
3.90–3.87 (m, 2H, H-4> + H-3), 3.83 (“t”, J = 9.7 Hz, 1H, H-
4), 3.79–3.73 (m, 3H, OCHaHbCH2 + H-6), 3.69 (ddd, J =
2.2, 5.9 Hz, 1H, H-5), 3.56 (td, J = 5.9, 9.9 Hz, 1H,
OCHaHbCH2), 2.84 (t, J = 6.4 Hz, 2H, SCH2), 2.69 (t, J =
6.7 Hz, 2H, CH2NHꢄ3Cl–), 2.60 (t, J = 7.3 Hz, 2H, CH2S),
2.06 (d>t>, J = 2.9, 13.2 Hz, 1H, H-3>a), 1.98 (d>t>, J =
4.2 Hz, 1H, H-3>b), 1.68–1.61 (m, 4H, OCH2CH2 + CH2CH2S),
1.48 (m, 2H, OCH2CH2CH2), 1.16 (d, 3H, H-6>). 13C NMR
(CD3OD, 600 MHz, from HMQC) ꢃ: 102.2 (C-1>, JC1>,H1>
=
167.3 Hz), 101.2 (C-1, JC1,H1 = 164.6 Hz), 81.1 (C-3), 74.5
(C-5), 72.0 (C-2), 69.8 (C-4>), 68.5 (OCH2), 67.6 (C-5>),
66.7 (C-4), 65.0 (C-2>), 62.7 (C-6), 41.2 (SCH2), 36.0
(C-3>), 34.8 (SCH2CH2), 32.0 (CH2S), 30.1 (OCH2CH2 +
CH2CH2S), 26.2 (OCH2CH2CH2), 16.7 (C-6>). HR-ES-MS
calcd. for C19H38NO9SNa+: 456.226729; found: 456.227016.
1
Data for 28ꢂ: [ꢀ]2D2 –114.8 (c 3.1, H2O). H NMR (CD3OD,
600 MHz) ꢃ: 5.84 (ddt, J = 6.6, 10.3, 17.0 Hz, 1H,
CH=CH2), 5.02 (m, 1H, CH=CHaHb), 4.95 (m, 1H,
CH=CHaHb), 4.78 (d, J = 1.7 Hz, 1H, H-1), 4.29 (d, J =
7.7 Hz, 1H, H-1>), 3.93 (dd, J = 3.3 Hz, 1H, H-2), 3.82 (dd,
J = 2.4, 11.9 Hz, 1H, H-6a), 3.75 (m, 2H, OCHaHbCH2 +
H-3), 3.69 (dd, J = 5.9 Hz, 1H, H-6b), 3.67 (“t”, J = 9.5 Hz,
1H, H-4), 3.55 (ddd, 1H, H-5), 3.45 (m, 2H, H-2> +
OCHaHbCH2), 3.35 (dq, J = 6.2, 9.3 Hz, 1H, H-5>), 3.24
(ddd, J = 4.6, 9.2, 11.2 Hz, 1H, H-4>), 2.27 (d>t>, J = 4.8,
12.1 Hz, 1H, H-3>a), 2.14 (m, 2H, CH2CH=CH2), 1.69 (m,
2H, OCH2CH2), 1.46 (d>t>, J = 11.7 Hz, 1H, H-3>b), 1.26 (d,
J = 6.2 Hz, 3H, H-6> ). HR-ES-MS calcd. for C17H30O9Na+:
401.178753; found: 401.179064.
5-(2-Aminoethanethio)pentyl 3,6-dideoxy-ꢀ-D-ribo-
hexopyranosyl-(1J3)-ꢀ-D-manno-pyranoside (hydrochlo-
ride salt) (2)
As described for 1, 28ꢀ (13 mg, 34.4 mol) was converted
1
to 2 (12 mg, 71%). [ꢀ]2D2 –171.8 (c 1.1, H2O). H NMR
(D2O, 600 MHz) ꢃ: 5.05 (d, J = 3.7 Hz, 1H, H-1>), 4.88 (d,
J = 1.8 Hz, 1H, H-1), 4.05 (dd, J = 3.1 Hz, 1H, H-2), 3.88
(m, 2H, H-3 + H-6a), 3.83 (“t”, J = 9.5 Hz, 1H, H-4), 3.81
(ddd, J = 4.8, 12.3 Hz, 1H, H-2>), 3.78–3.71 (m, 3H, H-6b +
OCHaHbCH2 + H-5>), 3.67 (ddd, J = 2.2, 6.0 Hz, 1H, H-5),
3.56 (td, J = 6.1, 9.9 Hz, 1H, OCHaHbCH2), 3.37 (ddd, J =
4.6, 9.5, 11.4 Hz, 1H, H-4> ), 3.21 (t, J = 6.8 Hz, 2H, SCH2),
2.84 (t, J = 6.8 Hz, 2H, CH2NHꢄ3Cl–), 2.62 (t, J = 7.3 Hz,
2H, CH2S), 2.13 (d>t>, J = 11.5 Hz, 1H, H-3>a), 1.78 (d>t>,
1H, H-3>b), 1.64 (m, 4H, OCH2CH2 + CH2CH2S), 1.48 (m,
2H, OCH2CH2CH2), 1.22 (d, J = 6.2 Hz, 3H, H-6>).
13C NMR (D2O, 600 MHz, from HMQC) ꢃ: 100.2 (C-1>,
JC1>,H1> = 168.0 Hz), 100.1 (C-1, JC1,H1 = 168.4 Hz), 79.2
(C-3), 73.6 (C-5), 70.9 (C-2), 70.4 (C-4>), 69.8 (C-5>), 68.3
(OCH2), 67.8 (C-2>), 66.7 (C-4), 61.6 (C-6), 39.0 (SCH2),
35.0 (C-3>), 30.3 (CH2S), 28.8 CH2NHꢄ3Cl–), 28.7
(OCH2CH2 + CH2CH2S), 25.2 (OCH2CH2CH2), 17.1 (C-6>).
HR-ES-MS calcd. for C19H38NO9S+: 456.226729; found:
456.226642.
4-Pentenyl 3,6-dideoxy-ꢀ-D-arabino-hexopyranosyl-
(1J3)-ꢀ-D-mannopyranoside (29)
Compound 26 (60 mg, 72 mol) was converted to 29
(23 mg, 84%) in the same manner as 24ꢀ. [ꢀ]2D2 47.2
(c 1.8, H2O). 1H NMR (D2O, 600 MHz) ꢃ: 5.94 (tdd, J = 6.6,
10.3, 16.9 Hz, 1H, CH=CH2), 5.11 (m, 1H, CH=CHaHb), 5.04
(m, 1H, CH=CHaHb), 4.90 (s, 1H, H-1>), 4.85 (s, 1H, H-1),
4.08 (m, 1H, H-2>), 4.05 (m, 1H, H-2), 3.89 (m, 2H, H-3 +
H-6a), 3.82 (qd, J = 6.2, 9.5 Hz, 1H, H-5>), 3.78 (“t”, J =
9.5 Hz, 1H, H-4), 3.77 (m, 2H, H-6b + OCHaHbCH2), 3.70
(ddd, J = 2.2, 5.9, 9.3 Hz, 1H, H-5), 3.63 (ddd, J = 4.6,
11.2 Hz, 1H, H-4>), 3.57 (dt, J = 6.0, 9.9 Hz, 1H,
OCHaHbCH2), 2.18 (m, 2H, CH2CH=CH2), 2.06 (d>t>, J =
4.0, 13.6 Hz, 1H, H-3>a), 1.90 (ddd, J = 2.9 Hz, 1H, H-3>b),
1.75 (m, 2H, OCH2CH2), 1.28 (d, 3H, H-6>). 13C NMR
(600 MHz, D2O, from HMQC) ꢃ: 138.2 (CH=CH2), 115.7
(CH=CH2), 102.1 (C-1>, JC1>,H1> = 170.7 Hz), 100.5 (C-1,
5-(2-Aminoethylthio)pentyl 3,6-dideoxy-ꢀ-D-arabino-
hexopyranosyl-(1J3)-ꢀ-D-manno-pyranoside, acetic acid
salt (3)
J
C1,H1 = 170.7 Hz), 78.5 (C-3), 73.7 (C-5), 70.9 (C-5>), 70.8
(C-2), 68.2 (OCH2 + C-2>), 67.6 (C-4>), 66.9 (C-4), 61.6
(C-6), 34.1 (C-3>), 30.4 (CH2CH=CH2), 28.5 (OCH2CH2),
17.4 (C-6>). HR-ES-MS calcd. for C17H30O9Na+:
401.178753; found: 401.178261.
As described for 1, 29 (20 mg, 53 mol) was converted to
3 and isolated as the acetate salt form after purification by
reverse-phase HPLC using a gradient of MeOH–H2O (con-
taining 0.3% acetic acid), (25.5 mg, 94%). [ꢀ]2D2 +54 (c 2.1,
1
H2O). H NMR (D2O, 600 MHz) ꢃ: 4.88 (s, 1H, H-1>), 4.84
5-(2-Aminoethylthio)pentyl 3,6-dideoxy-ꢀ-D-xylo-hexo-
pyranosyl-(1J3)-ꢀ-D-mannopyranoside, hydrochloride
salt (1)
(d, J = 1.7 Hz, 1H, H-1), 4.06 (dd, J = 3.1, 4.7 Hz, 1H, H-
2>), 4.03 (dd, J = 3.2 Hz, 1H, H-2), 3.88 (dd, J = 2.3,
12.3 Hz, 1H, H-6a), 3.87 (dd, J = 9.6 Hz, 1H, H-3), 3.78 (m,
3H, H-5> + H-6b + OCHaHbCH2), 3.75 (“t”, J = 9.6 Hz, 1H,
H-4), 3.67 (ddd, J = 6.0 Hz, 1H, H-5), 3.61 (ddd, J = 4.5,
9.3, 11.4 Hz, 1H, H-4>), 3.56 (td, J = 6.1, 9.9 Hz, 1H,
OCHaHbCH2), 3.21 (t, J = 6.7 Hz, 2H, SCH2), 2.85 (t, J =
6.6 Hz, 2H, CH2NHꢄ3OAc–), 2.62 (t, J = 7.3 Hz, 2H, CH2S),
2.04 (d>t>, J = 13.6 Hz, 1H, H-3>a), 1.94 (s, 3H, OAc), 1.87
(ddd, J = 14.0 Hz, 1H, H-3>b), 1.64 (m, 4H, OCH2CH2 +
Compound 27 (10 mg, 26.4 mol) and 2-aminoethanethiol
hydrochloride (15 mg, 0.13 mmol) were dissolved in anhyd
degassed MeOH (1 mL). The solution was stirred under ar-
gon for 48 h with irradiation by UV light of 254 nm wave-
length. The solvent was evaporated and the resulting residue
was purified by reverse-phase HPLC to give 1 (11.7 mg,
1
90%). [ꢀ]2D2 –127.2 (c 1.8, H2O). H NMR (D2O, 600 MHz)
ꢃ: 5.10 (d, J = 3.7 Hz, 1H, H-1>), 4.85 (d, J = 1.7 Hz,
© 2002 NRC Canada

1140
Can. J. Chem. Vol. 80, 2002
13. D.R. Bundle. Top. Curr. Chem. 154,
1 (1990), and
CH2CH2S), 1.48 (m, 2H, OCH2CH2CH2), 1.26 (d, J =
6.4 Hz, 3H, H-6>). 13C NMR (D2O, 600 MHz, from HMQC)
refs. therein.
14. A.A. Lindberg, R. Wollin, G. Gruse, and S.B. Svenson. Am.
Chem. Soc. Symp. Ser. 231, 83 (1983)
15. A. Zdanov, Y. Li, D.R. Bundle, S.-J. Deng, C.R. Mackenzie,
S.A. Narang, N.M. Young, and M. Cygler. Biochemistry, 33,
5172 (1994).
16. B.W. Sigurskjold and D.R. Bundle. J. Biol. Chem. 267, 8371
(1992).
17. B.W. Sigurskjold, E. Altman, and D.R. Bundle. Eur. J.
Biochem. 197, 239 (1991).
ꢃ: 101.9 (C-1>, JC1>,H1> = 171.4 Hz), 100.4 (C-1, JC1,H1
=
168.9 Hz), 78.9 (C-3), 73.8 (C-5), 71.0 (C-5>), 70.7 (C-2),
68.6 (OCH2), 68.1 (C-2>), 67.9 (C-4>), 66.8 (C-4), 61.6
(C-6), 39.0 (SCH2), 34.0 (C-3>), 31.5 (CH2S), 28.8
CH2NHꢄ3OAc– + OCH2CH2 + CH2CH2S), 26.0 (OCH2CH2CH2),
23.0 (OAc–), 17.0 (C-6> ). HR-ES-MS calcd. for
C19H38NO9S+: 456.226729; found: 456.227209.
18. C.R. Mackenzie, T. Hirama, S.-J. Deng, D.R. Bundle, S.A.
Narang, and N.M. Young. J. Biol. Chem. 271, 1527 (1995).
19. B. Fraser-Reid, U.E. Udodong, A. Wu, H. Ottosson, J.R.
Merritt, C.S. Ral, C. Roberts, and R. Madsen. Synlett, 927
(1992), and refs. therein.
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© 2002 NRC Canada