Carbohydrate-derived PSE acetals: Controlled base-induced ring cleavage

Article abstract of DOI:10.1016/j.tet.2011.11.009

Retro-Michael type reactions applied to PSE acetals protecting monosaccharides led either to complete removal or to ring-cleavage. In protic medium, application of standard basic conditions resulted in acetal deprotection, while the use of butyl lithium in aprotic medium allowed controlled ring-cleavage. A regio- and stereoselective C- over O-alkylation was observed during the process. Furthermore, depending on the substrates and the reaction conditions involved, new carbohydrate-derived β-alkoxyvinyl sulfones were obtained with varying regioselectivity.

Full text of DOI:10.1016/j.tet.2011.11.009

Tetrahedron 68 (2012) 544e551
Contents lists available at SciVerse ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Carbohydrate-derived PSE acetals: controlled base-induced ring cleavage
a
a
,
b
a
,
b
a,
*
*
ꢀ
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Florence Chery , Elena Cabianca , Arnaud Tatibouet , Ottorino De Lucchi , Patrick Rollin
a
ꢀ
ꢀ
ꢀ
Institut de Chimie Organique et Analytique, UMR 6005, Universite d’Orleans, B.P. 6759, F-45067 Orleans, France
Dipartimento di Chimica, Universita Ca’ Foscari di Venezia, Dorsoduro 2137, I-30123 Venezia, Italy
b
ꢁ
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 30 June 2011
Received in revised form 2 November 2011
Accepted 4 November 2011
Available online 11 November 2011
Retro-Michael type reactions applied to PSE acetals protecting monosaccharides led either to complete
removal or to ring-cleavage. In protic medium, application of standard basic conditions resulted in acetal
deprotection, while the use of butyl lithium in aprotic medium allowed controlled ring-cleavage. A regio-
and stereoselective C- over O-alkylation was observed during the process. Furthermore, depending on
the substrates and the reaction conditions involved, new carbohydrate-derived
were obtained with varying regioselectivity.
b-alkoxyvinyl sulfones
Keywords:
Acetal
Ó 2011 Elsevier Ltd. All rights reserved.
Phenylsulfonylethylidene
Alkoxyvinyl sulfones
Protecting group
Carbohydrate
1. Introduction
group through reductive cleavage of a CeS bond is a standard re-
action.11 In the present work, we report on the behaviour of pre-
viously described carbohydrate-derived PSE acetals1b,2 under
strongly basic conditions to explore the selective ring cleavage and
deprotection conditions.
We have introduced in the carbohydrate field phenyl-
sulfonylethylidene (PSE) acetals,1 which can readily be prepared
through a Michael-type reaction of the corresponding diols with
1,2-bis(phenylsulfonyl)ethylene (BPSE) (Scheme 1).
2. Results and discussion
2.1. Retro-Michael reaction for PSE acetal removal
From earlier results, it is known that PSE acetals are not affected
under acidic conditions;1b,2c contrastingly, they can undergo
cleavage under strongly reductive conditions (e.g., LiAlH41b) or
under strongly basic conditions (LiNH2 in liquid ammonia12). PSE
acetal removal should follow two consecutive retro-Michael type
reactions involving two possible isomeric intermediates A and B
(Scheme 2).
Taking into consideration that the previously reported condi-
tions to effect PSE acetal cleavage are particularly harsh and should
be modified, we have performed a preliminary study (Table 1) on
the reactivity of our standard1b,2a model substratedmethyl 2,3-di-
O-benzyl-4,6-O-(2-phenylsulfonyl)ethylidene-a-D-glucopyrano-
side 1 and other selected pyrano- and furano-type PSE acetals
(Scheme 3).
Deprotections under various protic conditions were first tested
on PSE acetal 1. This exploration (Table 1, entries 1e7) showed that
KOH or CsCO3 in refluxing EtOH effected total cleavage of the acetal
with reasonably good yields. In one case (entry 5) direct acetylation
of the crude mixture afforded the 4,6-di-O-acetyl derivative in 86%
Scheme 1. Synthesis of carbohydrate-derived PSE acetals.
Our previous studies have disclosed that those atypical PSE ac-
etals show striking properties2 compared to standard acetal pro-
tective groupsdnotably a strong reluctance to acid-catalyzed
hydrolysis. A major part of sulfone chemistry is dedicated to the
formation and reactivity of the derived stabilized carbanions.3 In
particular, simple
ation4 or in acylation5 reactions, in aldol-type reactions6 as well as
in Michael additions on
-unsaturated acceptors.7 Whereas an-
ions derived from -sulfonylated acetals have been studied exten-
a-sulfonyl carbanions have been used in alkyl-
a,b
g
sively,8 the reactivity of
b-acetalic sulfones in basic media was
scarcely investigated.9,10 On the other hand, elimination of a sulfone
* Corresponding authors. Tel.: þ33 (0)238 41 73 70; fax: þ33 (0)238 41 72 81;
€
e-mail address: arnaud.tatibouet@univ-orleans.fr (A. Tatibouet).
0040-4020/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2011.11.009

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F. Chery et al. / Tetrahedron 68 (2012) 544e551
545
useful alkoxyvinyl sulfones:12 applying a strong base in aprotic
conditions would cleave the PSE acetal ring to form isomeric in-
termediates A and B (Scheme 2).
Our model PSE acetal 1 was subjected to the conditions pre-
viously set up by Simpkins to convert PSE acetals into alkoxyvinyl
sulfones,9 using n-BuLi (2 equiv) in THF at ꢀ78 ꢁC, then quenching
the reaction with electrophilic speciesdnamely a protic acid or an
alkyl halide (Scheme 4). Proton-quenching by acetic acid resulted in
a ca. 1:1 mixture of regioisomeric alkoxyvinyl sulfones 5 and 6 in
which the double bond was shown to be exclusively E-con-
figurated. Alkyl halide quenching led in moderate yields to regioi-
someric pairs of C-alkylated b-alkoxyvinyl sulfones 7, 9 and 11e16.
Additionally, minor C-methylation of the phenyl group was detec-
ted in the sole case of 8/10.
Scheme 2. Suggested double retro-Michael mechanism for the cleavage of carbohy-
drate-derived PSE acetals.
Table 1
Base-induced cleavage of PSE acetals in protic solvents
Entry PSE acetal Base [c] Solvent
Temperature Time Yield
1
1
1
1
1
1
1
1
2
2
3
4
LiCl
MeOH/H2O rt
(1:1)
MeOH/H2O rt
(1:1)
24 h No reaction
24 h No reaction
16 h No reaction
2
NaOH
[1 M]
K2CO3
[0.35 M] (1:1)
KOH
3
EtOH/H2O
Reflux
4
EtOH
EtOH
EtOH
EtOH
Reflux
Reflux
Reflux
Reflux
Reflux
Reflux
Reflux
Reflux
3 h
5 h
5 h
3 h
51%
86%a
70%
69%
[0.5 M]
KOH
5
[0.5 M]
CsCO3
[0.4 M]
CsCO3
[0.5 M]
KOH
[1.5 M]
KOH
[0.5 M]
KOH
6
Scheme 4. Base-induced ring cleavage of PSE acetal 1 and C-alkylation.
7
The poorregioselectivityobserved between the primary (O-6) and
the secondary (O-4) positions on the carbohydrate template might
result from an equilibrium established in such conditions between
the cyclic acetal and open-chain anionic species (Scheme 5). The first
8
EtOH/H2O
(1:1)
EtOH
16 h 63%
16 h 65%
16 h 80%
9
10
11
EtOH
EtOH
equivalent of n-BuLi is used to extrude the proton
a to the sulfonyl
[0.5 M]
KOH
group; elimination then occurs with cleavage of the cyclic acetal A to
produce a vinyl sulfone B or C. The second equivalent of n-BuLi ex-
3 h
82%
[0.6 M]
trudes the most reactive
a-vinylic proton to form the stabilized
a
Per-O-acetylation was realized to optimize purification of the compound.
carbanion D or E, which finally attacks the electrophilic species to
stereoselectively afford the E-alkoxyvinyl sulfone.13
Scheme 3. PSE acetals examined in the base-induced deprotection assays.
yield. Application of the KOH/EtOH procedure to the
D-mannopyr-
anoside 2,1b the -allopyranoside 3,2a and the -xylofuranose 41b
D
D
led to similar deprotection yields, which compared favourably
with the results previously reported by us: using the LiAlH4/Et2O
procedure, PSE acetal cleavage of 1 and 4 was effected in 77% and
78% yields, respectively.1b Therefore it comes out that the above
protic conditions can advantageously be used for the deprotection
of PSE acetals.
Scheme 5. Intermediates in base-induced ring cleavage of a PSE acetal.
The retro-Michael O-regioselection outcome of the cleavage is
indeed disappointing. On the contrary, the regio- and stereo-
selectivities of the alkylation are far more satisfactory. No O-al-
kylation was detected whatever excess of electrophile used and
2.2. Retro-Michael reaction in controlled ring opening of PSE
acetals
a selective C-alkylation in
was observed. Eisch et al. have shown
a
position of the
b
-alkoxyvinyl sulfones
The retro-Michael process outlined in Scheme 2 allows to pre-
dict a possible controlled ring opening to produce synthetically
a-metallation of vinyl

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F. Chery et al. / Tetrahedron 68 (2012) 544e551
546
sulfones to be remarkably ‘locoselective’.14 In contrast to alkyl
substituted (Z)-1-(phenylsulfonyl)vinyllithium species, which are
known to isomerize quite slowly at ꢀ70 ꢁC, the alkoxy analogues
isomerize rapidly and completely into the E isomers, even at
ꢀ90 ꢁC. This may be facilitated by reduced double bond order in
a ‘pushepull’ olefin where stabilization of the E isomer is ascribed
a 1:1 mixture of regioisomers 19a and 19b, whereas the 3-O-benzyl
derivative 20 was converted into vinyl sulfones 20a and 20b in a 3.6
regioisomeric ratio in favour of the O-6 position. Finally, the 3-
deoxy derivative 21 underwent regiospecific ring opening to ex-
clusively afford the primary b-alkoxyvinyl sulfone 21a. The above
results may be explained by a more favourable chelation of the
vinylic carbanion on the O-6 position compared to the O-5 position.
Moreover, it clearly appears that the C-3 substituent plays a crucial
role in the equilibrium: when R¼OH, a strong interference of this
competing anionic pole is expected, while the chelating participa-
tion of R¼OBn would be much less. In the case when R¼H finally, no
interfering chelation can take place and the sole vinyl sulfone 21a is
isolated (Scheme 7). Altogether, it can be seen that base-induced
ring cleavage of PSE acetals favours the formation of primary
alkoxyvinyl sulfones: when connected on pyranose templates
(entries 1e4), 1,3-dioxanes do not show notable selectivity, while
connection on a furanose template (entry 5) greatly improves the
to lithium chelation by the b
-alkoxy substituent.15
Motivated by the overall efficacy of the initial transformation of
PSE acetal 1 into the mixture of regioisomeric alkoxyvinyl sulfones
2 and 3, we have tested an extension of the base-induced cleavage
to diverse PSE 1,3-dioxanes and -dioxolanes using acetic acid as
quenching reagent (Schemes 3 and 6).
selectivity ratio. D-Glucofuranose-derived 1,3-dioxolanes (entries
6e8) display flagrant variability depending on the group present on
the 3-position.
Scheme 6. Additional PSE acetals investigated in ring cleavage.
Scheme 7. Proposed competing chelations on
a D-glucofuranose frame.
PSE 1,3-dioxanes derived from
D
-mannose 2,
D
-galactose 171b
-glucoside 1
-allose 181b behaved similarly to the model
D
3. Conclusion
and
D
(Table 2). The related alkoxyvinyl sulfones were obtained in yields
ranging from ca. 70 to 80% with a 1.2e1.6 regioisomeric ratio in-
dicative of a slight preference for the O-6 position. Expectedly, this
lack of selectivity is in sharp contrast with the results previously
reported for BuLi-induced cleavage of PSE 1,3-oxathianes built on
Base-induced single or double retro-Michael type reactions
were performed on PSE acetal anchored onto monosaccharidic
frames. Under protic conditions, PSE acetals are removed to restore
the related 1,3-diols in preparative yields. Under aprotic strongly
basic conditions, PSE 1,3-dioxanes undergo very efficient ring
cleavage, the regioselectivity of which is fairly dependent on the
carbohydrate ring template: on pyrano frames, only a slight pre-
dominance of primary over secondary alkoxyvinyl sulfones is ob-
served, whereas a furano frame such as 21 clearly favours the
formation of the primary alkoxyvinyl sulfone. In other respects,
glucofuranose-based PSE 1,3-dioxolanes also show comparable
selectivity. Additionally, quenching experiments with alkyl halides
reveal a remarkably selective C- over O-alkylation. This preliminary
study significantly broadens the synthetic scope of PSE acetals,
which are not confined to diol protection and can find uses in se-
lective functionalization of appropriately designed carbohydrate
frameworks.
a D
-glucopyrano frame.16
Table 2
Base-induced cleavage of PSE acetals in aprotic medium
Entry
PSE acetal
Primary
b-O-vinyl
Secondary
b
-O-vinyl
a/b Ratio
sulfone a
sulfone b
1
3
2
4
5
6
7
8
1
2
5 (42%)
6 (37%)
1.1
1.2
1.6
1.3
12.5
1.0
2a (42%)
17a (43%)
18a (38%)
4a (88%)a
19a (43%)
20a (50%)
21a (82%)
2b (35%)
17b (26%)
18b (29%)a
4b (7%)a
19b (44%)
20b (14%)
21b (d)b
17
18
4
19
20
21
3.6
>15
a
Purified after O-silylation of the a, b mixture with TBSCl, Et3N and DMAP in
4. Experimental
CH2Cl2.
b
Not detected.
4.1. General methods
The case of 1,2-O-isopropylidene-3,5-O-(2-phenylsulfonyl)eth-
Solvents were dried and distilled by standard methods before
use. All reagents were of commercial quality (Acros, Aldrich or
Lancaster) and used without purification. Reactions were carried
out under argon and monitored by TLC analysis with silica gel
plates (Kieselgel 60F254, Merck). Compounds were visualised with
UV light and charring after a 10% H2SO4 ethanolic solution spray.
Column chromatography was performed on silica gel 60 M
(0.036e0.063 mm, Merck). IR absorption frequencies are given in
cmꢀ1. 1H NMR (250 MHz) and 13C NMR (62.6 MHz) spectra (CDCl3,
internal TMS) were recorded on a Bruker AVANCE DPX 250 spec-
ylidene-a-D
-xylofuranose 4,1b in which a PSE 1,3-dioxane is fused
with a furano frame, is dramatically different: the high yielding
(95%) base-induced cleavage preferentially affords the primary O-5
connected vinyl sulfone 4a with a regioisomeric ratio exceeding
12.5 (Table 2). Turning to the study of PSE 1,3-dioxolanes, we se-
lected 5,6-PSE acetal substrates built on the same 1,2-O-iso-
propylidene-a-D-glucofurano frame and differing only by their
substitution at C-3.1b BuLi-induced cleavage followed by acetic acid
quenching took place with 65e80% yields and led to strikingly di-
verse results. Ring opening of the 3-OH derivative 19 produced
trometer. Chemical shifts (d) are reported in parts per milllion

ꢀ
F. Chery et al. / Tetrahedron 68 (2012) 544e551
547
downfield from TMS, coupling constants (J) are reported in hertz
a colourless gum, [
a
]
20 ꢀ3 (c 1.1, CHCl3). 1H NMR
d
3.37 (s, 3H, OMe),
D
and refer to apparent peak multiplicity. Assignments are based on
H,H- and C,H-COSY experiments. Mass spectra were obtained using
Ion SprayÒ (IS) method with an API 300 Perkin Elmer SCIEX spec-
trometer. HR-ESI-TOF-MS was performed on a Micromass LC TOF
spectrometer. Optical rotations were measured at 20 ꢁC with
a Perkin Elmer 410 polarimeter.
3.42 (t, 1H, J3e4¼J4e5¼9.4, H-4), 3.49 (dd, 1H, J1e2¼3.6, J2e3¼9.4, H-
2), 3.71e3.79 (m, 1H, H-5), 3.75 (t,1H, J2e3¼J3e4¼9.4, H-3), 3.99 (dd,
1H, J5e6b¼5.1, J6ae6b¼11.3, H-6b), 4.09 (dd, 1H, J5e6a¼2.3,
J6ae6b¼11.3, H-6a), 4.59 (d, 1H, J1e2¼3.6, H-1), 4.65 and 4.76 (2d, AB
system, 2H, Jgem¼12.1, PhCH2O), 4.67 and 5.02 (2d, AB system, 2H,
0
0
0
Jgem¼11.5, PhCH2O), 5.74 (d,1H, J1 e2 ¼12.1, H-2 ), 7.30e7.37 (m,10H,
HeAr), 7.45e7.57 (m, 3H, meta, para-HePhSO2), 7.57 (d, 1H,
J1 e2 ¼12.1, H-1 ), 7.85 (d, 2H, Jvic¼7.2, ortho-HePhSO2). 13C NMR
0
0
0
4.2. Base-induced removal of PSE acetals
d
55.8 (OMe), 69.5 (C-5), 69.8 (C-4), 71.7 (C-6), 73.6, 75.8 (PhCH2O),
Typical procedure. PSE acetals (0.18 mmol) were dissolved in
a KOH/EtOH solution [0.6 M/3 mL]. The mixture was refluxed for
5 h, then cooled to rt, evaporated and directly purified by silica gel
column chromatography (petroleum ether/EtOAc 1:1). The ana-
lytical data obtained for the resulting diols are in agreement with
the literature.1b,2a
80.0 (C-2), 81.4 (C-3), 98.6 (C-1), 107.7 (C-20), 127.3, 128.0, 128.3,
128.5, 129.0, 129.7, 133.2 (CHeAr), 138.2, 138.9 (CIVeAr), 142.8
(CIVePhSO2), 161.6 (C-10). IR (film): 3570 (OH), 3056, 2933 (CHeAr,
]CH), 1628, 1610 (C]C), 1369, 1143 (PhSO2), 1028 (]CeOR). MS IS
m/z¼558.5 [MþNH4]þ, 563.5 [MþNa]þ. HRMS: C29H32O8S: calcd
540.1818; found 540.1810.
4.3. Base-induced controlled ring opening of PSE acetals
4.3.3. Methyl 2,3-di-O-benzyl-6-O-[(E)-20-(phenylsulfonyl)prop-10-
enyl]-a-D-glucopyranoside (7). Obtained from 1 by quenching with
Typical procedure. To a dry THF solution (5 mL) of the PSE acetal
(0.9 mmol) maintained at ꢀ78 ꢁC under argon, 3 equiv n-BuLi
(2.5 M solution in hexane) was added dropwise, giving rise to a red
colour. After 10 min, the mixture was quenched by an electrophilic
reagent (5 equiv), then allowed to warm up to rt and poured into
cold water. After extraction (3ꢂ) with EtOAc, the combined organic
phases were dried over MgSO4; after filtration and concentration of
the solution in vacuo, the residue was purified by silica gel column
chromatography.
methyl iodide; silica gel column chromatography (petroleum ether/
EtOAc 9:1, 8:2, 7:3, 6:4 then 1:1) afforded compound 7 with 33%
yield as a colourless gum, [
a
]
20þ22 (c 1.3, CHCl3). 1H NMR
d 1.70 (s,
D
3H, Me), 3.31 (s, 3H, OMe), 3.38 (t,1H, J3e4¼J4e5¼9.6, H-4), 3.49 (dd,
1H, J1e2¼3.6, J2e3¼9.6, H-2), 3.76 (t, 1H, J2e3¼J3e4¼9.6, H-3),
3.65e3.78 (m, 1H, H-5), 4.16 (dd, 1H, J5e6b¼5.3, J6ae6b¼11.7, H-6b),
4.27 (dd, 1H, J5e6a¼1.9, J6ae6b¼11.7, H-6a), 4.63 (d, 1H, J1e2¼3.6, H-
1), 4.66 and 5.03 (2d, AB system, 2H, Jgem¼11.5, PhCH2O), 4.68 and
4.77 (2d, AB system, 2H, Jgem¼11.7, PhCH2O), 7.29e7.56 (m, 14H,
Silylation. A selective silylation of the primary hydroxyl was
HeAr, H-10), 7.82 (d, 2H, Jvic¼7.2, ortho-HePhSO2). 13C NMR
d 9.4
applied when the regioisomeric
be readily separated by column chromatography. The crude mix-
ture of -alkoxyvinyl sulfones (<0.9 mmol) was dissolved in dry
b
-alkoxyvinyl sulfones could not
(Me), 55.7 (OMe), 69.8 (C-4), 70.5 (C-5), 73.6 (C-6), 73.9, 75.9
(PhCH2O), 80.2 (C-2), 81.5 (C-3), 98.4 (C-1), 115.2 (C-20), 126.3, 127.9,
128.5, 129.0, 129.1, 129.3, 133.1 (CHeAr), 138.3, 138.9 (CIVeAr), 140.9
(CIVePhSO2), 157.4 (C-10). IR (film): 3545 (OH), 3054, 2986 (CHeAr,
]CH), 1651 (C]C). MS IS m/z¼523.5 [MꢀOMe]þ, 572.5 [MþNH4]þ,
577.5 [MþNa]þ, 593.5 [MþK]þ. HRMS: C30H34O8S: calcd 554.1974;
found 554.1961.
b
DMF (10 mL) under argon. After cooling to 0 ꢁC, Et3N (1 equiv),
TBDMSCl (1 equiv) and DMAP (0.5 equiv) were added and the
mixture was then stirred 12 h at rt. The mixture was treated with
cold water and diluted with EtOAc (10 mL) then decanted. The or-
ganic phase was washed with water, then dried over MgSO4; after
filtration and concentration of the solution in vacuo, the residue
was purified by column chromatography.
4.3.4. Methyl 2,3-di-O-benzyl-4-O-[(E)-20-(phenylsulfonyl)prop-10-
enyl]-a-D-glucopyranoside (9). Obtained as co-product in the above
reaction; silica gel column chromatography (petroleum ether/
4.3.1. Methyl 2,3-di-O-benzyl-6-O-[(E)-20-(phenylsulfonyl)vinyl]-
-glucopyranoside (5). Obtained from methyl 2,3-di-O-benzyl-4,6-
a-
EtOAc 9:1, 8:2, 7:3, 6:4 then 1:1) afforded compound 9 with 30%
20
D
yield as a colourless gum, [
a
]
þ15 (c 1, CHCl3). 1H NMR
d 1.68 (s,
D
O-(2-phenylsulfonyl)ethylidene-
a
-
D
-glucopyranoside
1
[280557-
3H, Me), 3.39 (s, 3H, OMe), 3.52 (dd, 1H, J1e2¼3.4, J2e3¼9.1, H-2),
3.59e3.80 (m, 3H, H-5, H-6a, H-6b), 3.93 (t, 1H, J2e3¼J3e4¼9.1, H-3),
4.01 (t, 1H, J3e4¼J4e5¼9.1, H-4), 4.59 (d, 1H, J1e2¼3.4, H-1), 4.63 and
4.77 (2d, AB system, 2H, Jgem¼11.9, PhCH2O), 4.64 and 4.84 (2d, AB
system, 2H, Jgem¼11.1, PhCH2O), 7.26e7.35 (m, 10H, HeAr), 7.40 (t,
2H, Jvic¼7.7, meta-HePhSO2), 7.54 (t, 2H, Jvic¼7.7, para-HePhSO2),
7.59 (s, 1H, H-10), 7.75 (d, 2H, Jvic¼7.7, ortho-HePhSO2). 13C NMR
34-8]1b by quenching with acetic acid (method A); silica gel column
chromatography (petroleum ether/EtOAc 7:3, 6:4 then 1:1) affor-
ded compound 5 with 42% yield as a colourless gum, [
1.2, CHCl3). 1H NMR
a
]
20þ23 (c
D
d
3.37 (s, 3H, OMe), 3.50 (dd, 1H, J1e2¼3.8,
J2e3¼9.4, H-2), 3.60e3.79 (m, 3H, H-5, H-6a, H-6b), 3.92 (t, 1H,
J2e3¼J3e4¼9.4, H-3), 4.02 (t, 1H, J3e4¼J4e5¼9.4, H-4), 4.58 (d, 1H,
J1e2¼3.8, H-1), 4.61 and 4.76 (2d, AB system, 2H, Jgem¼12.1,
PhCH2O), 4.63 and 4.83 0(2d, AB system, 2H, Jgem¼11.1, PhCH2O), 5.85
d
9.5 (Me), 55.9 (OMe), 61.2 (C-6), 69.8 (C-5), 73.9, 75.7 (PhCH2O),
79.8 (C-2, C-3), 82.2 (C-4), 98.6 (C-1), 115.7 (C-20), 127.9, 128.1, 128.2,
128.5, 128.8, 128.9, 129.4 (CHeAr), 133.1 (CHepara-PhSO2), 138.1,
138.3 (CIVeAr), 140.7 (CIVePhSO2), 156.7 (C-10). IR (film): 3417 (OH),
3054, 2975 (CHeAr, ]CH), 1651 (C]C), 1055 (]CeOR). MS IS m/
z¼555.5 [MþH]þ, 572.5 [MþNH4]þ, 577.5 [MþNa]þ, 593.5 [MþK]þ.
HRMS: C30H34O8S: calcd 554.1974; found 554.1965.
0
0
(d, 1H, J1 e2 ¼11.7, H-2 ), 7.31e7.36 (m, 10H, HeAr), 7.41 (t, 2H,
Jvic¼7.7, meta-HePhSO20 ), 7.54 (t, 1H, Jvic¼7.7, para-HePhSO2), 7.61
(d, 1H, J1 e2 ¼11.7, H-1 ), 7.78 (d, 2H, Jvic¼7.7, ortho-HePhSO2). 13C
0
0
NMR
d 55.9 (OMe), 60.9 (C-6), 69.5 (C-5), 73.9, 75.8 (PhCH2O), 79.6
(C-2), 79.8 (C-3), 81.9 (C-4), 98.5 (C-1), 105.6 (C-20), 127.4,
128.1, 128.3, 128.4, 128.8, 129.0, 129.7, 133.2 (CHeAr), 134.9, 135.1
(CIVeAr), 141.4 (CIVePhSO2), 158.7 (C-10). IR (film): 3498 (OH), 3064,
3032, 2927 (CHeAr, ]CH), 1724, 1701, 1625 (C]C), 1373, 1139
(PhSO2), 952 (]CeOR). MS IS m/z¼558.5 [MþNH4]þ, 563.5
[MþNa]þ. HRMS: C29H32O8S: calcd 540.1818; found 540.1813.
4.3.5. Methyl 2,3-di-O-benzyl-6-O-[(E)-20-(ortho-tolylsulfonyl)prop-
10-enyl]-
a-D-glucopyranoside (8). Obtained as minor side-product
in the above reaction; silica gel column chromatography (petro-
leum ether/EtOAc 9:1, 8:2, 7:3, 6:4 then 1:1) afforded compound 8
with 7% yield as a colourless gum, [
d 1.63 (s, 3H, Me), 2.48 (s, 3H, PhMe), 3.34 (s, 3H, OMe), 3.41 (t, 1H,
a
]
20 þ15 (c 1.6, CHCl3). 1H NMR
D
4.3.2. Methyl 2,3-di-O-benzyl-4-O-[(E)-20-(phenylsulfonyl)vinyl]-
-glucopyranoside (6). Obtained as co-product in the above re-
a-
D
J3e4¼J4e5¼9.1, H-4), 3.48 (dd, 1H, J1e2¼3.6, J2e3¼9.6, H-2),
3.71e3.74 (m,1H, H-5), 3.77 (t,1H, J2e3¼J3e4¼9.1, H-3), 4.20 (dd,1H,
J5e6b¼4.9, J6ae6b¼11.5, H-6b), 4.26 (dd, 1H, J5e6a¼2.7, J6ae6b¼11.5,
action; silica gel column chromatography (petroleum ether/EtOAc
7:3, 6:4 then 1:1) afforded compound 6 with 37% yield as

ꢀ
F. Chery et al. / Tetrahedron 68 (2012) 544e551
548
H-6a), 4.61 (d, 1H, J1e2¼3.6, H-1), 4.67 and 4.78 (2d, AB system, 2H,
Jgem¼12.1, PhCH2O), 4.69 and 5.03 (2d, AB system, 2H, Jgem¼11.5,
PhCH2O), 7.20e7.48 (m, 15H, HeAr, HeArSO2, H-10), 7.99 (d, 2H,
7.74 (d, 2H, Jvic¼7.6, ortho-HePhSO2). 13C NMR
d 14.3 (Me), 21.7
(CH2b), 26.9 (CH2g), 55.8 (OMe), 61.2 (C-6), 69.7 (C-5), 73.8, 75.7
(PhCH2O), 79.9 (C-2, C-3), 82.4 (C-4), 98.6 (C-1), 119.8 (C-20), 128.0,
128.5, 128.8, 128.9, 129.1, 129.3, 129.5 (CHeAr), 133.2 (CHepara-
PhSO2), 138.1, 138.4 (CIVeAr), 141.5 (CIVePhSO2), 157.8 (C-10). IR
(film): 3486 (OH), 3062, 3031, 2960, 2931, 2872 (CHeAr, ]CH),
1735, 1641 (C]C), 1369, 1157 (PhSO2), 980 (]CeOR). MS IS m/
z¼600.5 [MþNH4]þ, 605.5 [MþNa]þ. HRMS: C32H38O8S: calcd
582.2287; found 582.2283.
Jvic¼7.6, ortho-HeArSO2). 13C NMR
d 9.3 (Me), 20.2 (PhMe), 55.7
(OMe), 69.7 (C-4), 70.5 (C-5), 73.8 (C-6), 73.6, 75.9 (PhCH2O), 80.1
(C-2), 81.6 (C-3), 98.4 (C-1), 113.2 (C-20), 126.3 126.7, 128.5, 129.0,
129.1, 130.6, 132.9 (CHeAr), 133.4 (CHepara-PhSO2), 138.0, 138.4,
139.0 (CIVeAr), 158.0 (C-10). IR (film): 3548 (OH), 3048, 2983
(CHeAr, ]CH),1627 (C]C). MS IS m/z¼537.5 [MꢀOMe]þ, 586.5
[MþNH4]þ, 591.5 [MþNa]þ, 607.5 [MþK]þ. HRMS: C31H36O8S: calcd
568.2131; found 568.2119.
4.3.9. Methyl 2,3-di-O-benzyl-6-O-[(E)-30-phenyl-20-(phenylsulfonyl)
prop-10-enyl]-
a-D
-glucopyranoside (13). Obtained from
1
by
4.3.6. Methyl 2,3-di-O-benzyl-4-O-[(E)-20-(ortho-tolylsulfonyl)prop-
quenching with benzyl bromide; silica gel column chromatography
(petroleum ether/EtOAc 7:3, 65:35, 6:4, 55:45 then 1:1) afforded
10-enyl]-
a-D
-glucopyranoside (10). Obtained as minor side-product
20
in the above reaction; silica gel column chromatography (petro-
compound 13 with 32% yield as a colourless gum, [
a
]
þ15 (c 1.1,
D
leum ether/EtOAc 9:1, 8:2, 7:3, 6:4 then 1:1) afforded compound 10
CHCl3). 1H NMR
d
3.24 (t, 1H, J3e4¼J4e5¼9.1, H-4), 3.26 (s, 3H, OMe),
with 5% yield as a colourless gum, [
a
]
20 þ10 (c 1.9, CHCl3). 1H NMR
3.41 (dd, 1H, J1e2¼3.6, J2e3¼9.1, H-2), 3.55 (s, 2H, PhCH2eC),
3.67e3.77 (m,1H, H-5), 3.73 (t,1H, J2e3¼J3e4¼9.1, H-3), 4.19 (dd,1H,
J5e6b¼5.3, J6ae6b¼11.9, H-6b), 4.29 (dd,1H, J5e6a¼2.1, J6ae6b¼11.9, H-
6a), 4.62 (d, 1H, H-1, J1e2¼3.6), 4.66 and 4.76 (2d, AB system, 2H,
Jgem¼12.1, PhCH2O), 4.67 and 5.02 (2d, AB system, 2H, Jgem¼11.5,
PhCH2O), 6.97e7.04 (m, 5H, PhCH2eC), 7.22e7.44 (m, 13H, HeAr,
meta-, para-HePhSO2), 7.61 (s, 1H, H-10), 7.68 (d, 2H, Jvic¼7.7, ortho-
D
d
1.63 (s, 3H, Me), 2.45 (s, 3H, PhMe), 3.38 (s, 3H, OMe), 3.52 (dd, 1H,
J1e2¼3.4, J2e3¼9.1, H-2), 3.62e3.81 (m, 3H, H-5, H-6a, H-6b),
3.59e3.80 (m, 3H, H-5, H-6a, H-6b), 3.96 (t, 1H, J2e3¼J3e4¼9.1, H-3),
4.02 (t, 1H, J3e4¼J4e5¼9.1, H-4), 4.59 (d, 1H, J1e2¼3.4, H-1), 4.64 and
4.79 (2d, AB system, 2H, Jgem¼11.9, PhCH2O), 4.67 and 4.86 (2d, AB
system, 2H, Jgem¼11.1, PhCH2O), 7.19e7.54 (m, 15H, HeAr, HeArSO2,
H-10), 7.99 (d, 2H, ortho-HeArSO2, Jvic¼7.7). 13C NMR
d
9.5 (Me), 20.3
HePhSO2). 13C NMR
d 30.5 (PhCH2-C), 55.7 (OMe), 69.7 (C-4), 70.4
(PhMe), 55.9 (OMe), 61.1 (C-6), 69.8 (C-5), 73.9, 75.9 (PhCH2O), 79.6
(C-3), 79.9 (C-2), 82.4 (C-4), 98.6 (C-1), 114.7 (C-20), 126.6, 128.1,
128.5, 128.8, 128.9, 130.6, 133.1 (CHeAr), 133.4 (CHepara-PhSO2),
137.7, 138.2, 138.4 (CIVeAr), 157.2 (C-10). IR (film): 3425 (OH), 3049,
2972 (CHeAr, ]CH), 1641 (C]C), 1032 (]CeOR). MS IS m/z¼586.5
[MþNH4]þ, 591.5 [MþNa]þ, 307.5 [MþK]þ. HRMS: C31H36O8S: calcd
568.2131; found 568.2116.
(C-5), 73.5, 75.7 (PhCH2O), 74.4 (C-6), 80.1 (C-2), 81.4 (C-3), 98.5 (C-
1), 118.8 (C-20), 126.5, 127.3, 127.9, 128.4, 128.5, 128.9, 129.0,
129.1, 129.5 (CHeAr), 132.8 (CHeparaePhSO2), 138.0, 138.3, 139.0
(CIVeAr), 141.7 (CIVePhSO2), 159.3 (C-10). IR (film): 3475 (OH), 2934
(CHeAr, ]CH), 1651 (C]C), 1373, 1140 (PhSO2). MS IS m/z¼599.5
[MꢀOMe]þ, 631.5 [MþH]þ, 648.5 [MþNH4]þ, 653.5 [MþNa]þ, 669.5
[MþK]þ. HRMS: C36H38O8S: calcd 630.2287; found 630.2290.
4.3.7. Methyl 2,3-di-O-benzyl-6-O-[(E)-20-(phenylsulfonyl)pent-10-
4.3.10. Methyl
2,3-di-O-benzyl-4-O-[(E)-30-phenyl-20-(phenyl-
-glucopyranoside (14). Obtained as co-
enyl]-
a
-D-glucopyranoside (11). Obtained from 1 by quenching with
sulfonyl)prop-10-enyl]-
a-D
n-propyl iodide; silica gel column chromatography (petroleum
ether/EtOAc 7:3, 65:35, 6:4, 55:45 then 1:1) afforded compound 11
product in the above reaction; silica gel column chromatography
(petroleum ether/EtOAc 7:3, 65:35, 6:4, 55:45 then 1:1) afforded
20
with 32% yield as a colourless gum, [
a]
20 þ14 (c 2.8, CHCl3). 1H NMR
compound 14 with 20% yield as a colourless gum, [
a
]
D
ꢀ7 (c 1.8,
D
d
0.76 (t, 3H, Jvic¼7.4, Me), 1.21e1.38 (m, 2H, CH2b), 2.06e2.13 (m,
CHCl3). 1H NMR
d 3.37 (s, 3H, OMe), 3.51 (s, 2H, PhCH2eC), 3.49 (dd,
2H, CH2g), 3.31 (s, 3H, OMe), 3.33e3.40 (m, 1H, H-4), 3.47 (dd, 1H,
J1e2¼3.8, J2e3¼9.4, H-2), 3.71e3.77 (m, 1H, H-5), 3.76 (t, 1H,
J2e3¼J3e4¼9.4, H-3), 4.14 (dd, 1H, J5e6b¼5.8, J6ae6b¼11.7, H-6b), 4.28
(dd, 1H, J5e6a¼1.9, J6ae6b¼11.7, H-6a), 4.63 (d, 1H, J1e2¼3.8, H-1),
4.66 and 4.77 (2d, AB system, 2H, Jgem¼11.9, PhCH2O), 4.68 and 5.03
(2d, AB system, 2H, Jgem¼11.5, PhCH2O), 7.29e7.57 (m, 14H, HeAr,
HePhSO2, H-10), 7.82 (d, 2H, Jvic¼7.4, ortho-HePhSO2). 13C NMR
1H, J1e2¼3.6, J2e3¼9.1, H-2), 3.54e3.65 (m, 3H, H-5, H-6a, H-6b),
3.84 (t, 1H, J2e3¼J3e4¼9.1, H-3), 4.01 (t, 1H, J3e4¼J4e5¼9.1, H-4), 4.45
and 4.78 (2d, AB system, 2H, Jgem¼11.1, PhCH2O), 4.56 (d, 1H,
J1e2¼3.6, H-1), 4.60 and 4.74 (2d, AB system, 2H, Jgem¼12.1,
PhCH2O), 6.91e6.97 (m, 2H, PhCH2eC), 7.01e7.06 (m, 3H,
PhCH2eC), 7.23e7.46 (m, 13H, HeAr, meta-, para-HePhSO2), 7.64 (d,
2H, Jvic¼7.5, ortho-HePhSO2), 7.74 (s, 1H, H-10). 13C NMR
d 30.7
d
14.4 (Me), 21.6 (CH2b), 26.8 (CH2g), 55.8 (OMe), 70.0 (C-4), 70.7 (C-
(PhCH2eC), 55.9 (OMe), 61.1 (C-6), 69.6 (C-5), 73.9, 75.5 (PhCH2O),
79.8 (C-2, C-3), 82.4 (C-4), 98.6 (C-1),119.3 (C-20),126.5,127.9,128.0,
128.3, 128.4, 128.5, 128.8, 128.9, 129.2 (CHeAr), 132.9 (CHepara-
PhSO2), 137.9, 138.0, 138.4 (CIVeAr), 141.4 (CIVePhSO2), 158.4 (C-10).
IR (film): 3484 (OH), 3062, 3031, 2927 (CHeAr, ]CH), 1639, 1602
(C]C), 1147 (PhSO2), 910 (]CeOR). MS IS m/z¼599.5 [MꢀOMe]þ,
631.5 [MþH]þ, 648.5 [MþNH4]þ, 653.5 [MþNa]þ, 669.5 [MþK]þ.
HRMS: C36H38O8S: calcd 630.2287; found 630.2294.
5), 73.6, 75.8 (PhCH2O), 74.3 (C-6), 80.1 (C-2), 81.5 (C-3), 98.4 (C-1),
119.2 (C-20),127.9,128.1,128.3,128.5,128.7,128.8,128.9,129.3,129.6
(CHeAr), 133.0 (CHepara-PhSO2), 138.3, 138.4, 138.9 (CIVeAr), 158.7
(C-10). IR (film): 3489 (OH), 3063, 3031, 2960, 1932, 2872 (CHeAr,
]CH), 1724, 1640 (C]C), 1157 (PhSO2), 1049 (]CeOR). MS IS
m/z¼600.5 [MþNH4]þ, 605.5 [MþNa]þ. HRMS: C32H38O8S: calcd
582.2287; found 582.2278.
4.3.8. Methyl 2,3-di-O-benzyl-4-O-[(E)-20-(phenylsulfonyl)pent-10-
4.3.11. Methyl
10,40-dienyl]-
2,3-di-O-benzyl-6-O-[(E)-20-(phenylsulfonyl)penta-
-glucopyranoside (15). Obtained from by
enyl]-
a
-D-glucopyranoside (12). Obtained as co-product in the
a
-D
1
above reaction; silica gel column chromatography (petroleum
quenching with allyl bromide; silica gel column chromatography
ether/EtOAc 7:3, 65:35, 6:4, 55:45 then 1:1) afforded compound 12
(petroleum ether/EtOAc 9:1, 8:2, 7:3, 6:4 then 1:1) afforded com-
20
with 20% yield as a colourless gum, [
a
]
20 ꢀ12 (c 2.1, CHCl3). 1H NMR
pound 15 with 26% yield as a colourless gum, [
a
]
þ20 (c 1.2,
D
D
CHCl3). 1H NMR
d
2.25 (s, 1H, OH), 2.92 (t, 2H, J3 ae4 ¼J3 be4 ¼6.4,
0
0
0
0
d
0.77 (t, 3H, Jvic¼7.4, Me), 1.26e1.38 (m, 2H, CH2b), 2.06e2.16 (m,
J3 ae5 a¼J3 be5 a¼J3 ae5 b¼J3 be5 b<0.5, H-30a, H-30b), 3.31 (s, 3H,
OMe), 3.34e3.40 (m, 1H, H-4), 3.46 (dd, 1H, J1e2¼3.4, J2e3¼9.1, H-2),
3.30e3.79 (m,1H, H-5), 3.76 (t,1H, J2e3¼J3e4¼9.1, H-3), 4.16 (dd,1H,
J5e6b¼5.5, J6ae6b¼11.9, H-6b), 4.29 (dd,1H, J5e6a¼1.9, J6ae6b¼11.9, H-
6a), 4.62 (d, 1H, J1e2¼3.4, H-1), 4.66 and 4.77 (2d, AB system, 2H,
Jgem¼12.3, PhCH2O), 4.68 and 5.03 (2d, AB system, 2H, Jgem¼11.5,
0
0
0
0
0
0
0
0
2H, CH2g), 3.39 (s, 3H, OMe), 3.53 (dd, 1H, J1e2¼3.4, J2e3¼9.2, H-2),
3.63e3.80 (m, 3H, H-5, H-6a, H-6b), 3.94 (t,1H, J2e3¼J3e4¼9.2, H-3),
4.04 (t, 1H, J3e4¼J4e5¼9.2, H-4), 4.61 (d, 1H, J1e2¼3.4, H-1), 4.62 and
4.87 (2d, AB system, 2H, Jgem¼11.1, PhCH2O), 4.63 and 4.75 (2d, AB
system, 2H, Jgem¼11.9, PhCH2O), 7.25e7.39 (m, 12H, HeAr, meta-
HePhSO2), 7.51 (t, 1H, Jvic¼7.6, para-HePhSO2), 7.66 (s, 1H, H-10),

ꢀ
F. Chery et al. / Tetrahedron 68 (2012) 544e551
549
0
0
0
0
0
0
PhCH2O), 4.78 (dd, 1H, J3 ae5 b¼J3 be5 b<0.5, J4 e5 b¼10.0,
PhCH2O), 4.66 and 4.84 (2d, AB system, 2H, Jgem¼10.8, PhCH2O),
J5 ae5 b¼1.5, H-50b), 4.85 (dd, 1H, J3 ae5 a¼J3 be5 a<0.5, J4 e5 a¼16.6,
5.86 (d, 1H, J1 e2 ¼11.7, H-2 ), 7.25e7.36 (m, 10H, HeAr), 7.39 (t, 2H,
Jvic¼7.7, meta-HePhSO2), 7.61 (t, 1H, Jvic¼7.7, para-HePhSO2), 7.61
0
0
0
0
0
0
0
0
0
0
0
J5 ae5 b¼1.5, H-50a), 5.50 (ddt, 1H, J3 ae4 ¼J3 be4 ¼6.4, J4 e5 a¼16.6,
0
0
0
0
0
0
0
0
J4 e5 b¼10.0, H-40), 7.23e7.57 (m, 14H, HeAr, HePhSO2, H-10), 7.82
(d, 1H, J1 e2 ¼11.7, H-1 ), 7.73 (d, 2H, Jvic¼7.7, ortho-HePhSO2). 13C
0
0
0
0
0
(d, 2H, Jvic¼7.4, ortho-HePhSO2). 13C NMR
d
28.9 (C-30), 55.7 (OMe),
NMR d 57.7 (OMe), 60.4 (C-6), 73.5 (C-5), 73.9, 75.6 (PhCH2O), 79.7,
69.8 (C-4), 70.5 (C-5), 73.6, 75.8 (PhCH2O), 74.4 (C-6), 80.1 (C-2),
81.4 (C-3), 98.4 (C-1), 116.4 (C-50), 117.4 (C-20), 128.1, 128.4, 128.5,
129.0, 129.1, 129.3 (CHeAr), 133.1 (CHepara-PhSO2), 133.7 (C-40),
138.2,138.9 (CIVeAr),141.6 (CIVePhSO2),158.9 (C-10). IR (film): 3489
(OH), 3063, 3032, 2931 (CHeAr, ]CH), 1641 (C]C), 1353, 1131
(PhSO2), 914 (]CeOR). MS IS m/z¼598.5 [MþNH4]þ, 603.5
[MþNa]þ. HRMS: C32H36O8S: calcd 580.2131; found 580.2118.
80.1 (C-2, C-3, C-4), 105.2 (C-1), 107.4 (C-20), 127.3, 128.1, 128.4,
128.7, 129.0, 129.5 (CHeAr), 133.1 (CHepara-PhSO2), 137.9, 138.8
(CIVeAr), 142.7 (CIVePhSO2), 163.1 (C-10). IR (film): 3488 (OH), 3065,
3029, 2929, 2873 (CHeAr, ]CH),1626, 1610 (C]C), 1385, 1142
(PhSO2), 976, 853 (]CeOR). MS IS m/z¼558.5 [MþNH4]þ, 563.5
[MþNa]þ, 579.5 [MþK]þ. HRMS: C29H32O8S: calcd 540.1818; found
540.1821.
4.3.12. Methyl
10,40-dienyl]-
2,3-di-O-benzyl-4-O-[(E)-20-(phenylsulfonyl)penta-
-glucopyranoside (16). Obtained as co-product in the
4.3.15. Methyl 2,3-di-O-benzyl-6-O-[(E)-20-(phenylsulfonyl)vinyl]-
-mannopyranoside (2a). Obtained from methyl 2,3-di-O-benzyl-
a-
a
-D
D
above reaction; silica gel column chromatography (petroleum ether/
EtOAc 9:1, 8:2, 7:3, 6:4 then 1:1) afforded compound 16 with 20%
4,6-O-(2-phenylsulfonyl)ethylidene-
a
-
D
-mannopyranoside
2
[280557-35-9]1b by quenching with acetic acid; silica gel column
yield as a colourless gum, [
a
]
20 ꢀ21 (c 1.2, CHCl3). 1H NMR
d 2.92 (t,
chromatography (petroleum ether/EtOAc 7:3, 65:35, 6:4 then 1:1)
D
0
2H, J3 ae4 ¼J3 be4 ¼6.4, J3 ae5 a¼J3 be5 a¼J3 ae5 b¼J3 be5 b<0.5, H-30a,
H-30b), 3.39 (s, 3H, OMe), 3.53 (dd, 1H, J1e2¼3.4, J2e3¼9.2, H-2),
3.66e3.79 (m, 3H, H-5, H-6a, H-6b), 3.92 (t, 1H, J2e3¼J3e4¼9.2, H-3),
4.03 (t, 1H, J3e4¼J4e5¼9.2, H-4), 4.56 (d, 1H, J1e2¼3.4, H-1), 4.62 and
4.76 (2d, AB system, 2H, Jgem¼11.9, PhCH2O), 4.65 and 4.86 (2d, AB
afforded compound 2a with 42% yield as a colourless gum, [
(c 2.6, CHCl3). 1H NMR
a
]
20 ꢀ2
0
0
0
0
0
0
0
0
0
0
0
D
d
3.28 (s, 3H, OMe), 3.65 (dd, 1H, J2e3¼3.2,
J3e4¼9.3, H-3), 3.71e3.80 (m, 2H, H-2, H-5), 3.90 (t, 1H,
J3e4¼J4e5¼9.3, H-4), 4.04 (dd, 1H, J5e6b¼6.2, J6ae6b¼11.0, H-6b), 4.18
(d, 1H, J5e6a<0.5, J6ae6b¼11.0, H-6a), 4.40 and 4.56 (2d, AB system,
2H, Jgem¼11.5, PhCH2O), 4.59 and 4.66 (2d, AB system, 2H, Jgem¼12.1,
0
0
0
0
system, 2H, Jgem¼11.5, PhCH2O), 4.79 (dd, 1H, J3 ae5 b¼J3 be5 b<0.5,
J4 e5 b¼9.8, J5 ae5 b¼1.5, H-50b), 4.85 (dd, 1H, J3 ae5 a¼J3 be5 a<0.5,
PhCH2O), 4.72 (s, 1H, J1e2<0.5, H-1), 5.76 (d, 1H, J1 e2 ¼12.1, H-2 ),
7.25e7.37 (m, 10H, HeAr), 7.47 (t, 2H, Jvic¼7.1, meta-HePh0SO2), 7.53
0
0
0
0
0
0
0
0
0
0
0
J4 e5 a¼16.4, J5 ae5 b¼1.5, H-50a), 5.47 (ddt, 1H, J3 ae4 ¼J3 be4 ¼6.4,
0
0
0
0
0
0
0
0
J4 e5 a¼16.4, J4 e5 b¼9.8, H-40), 7.30e7.39 (m, 12H, HeAr, meta-
(t, 1H, Jvic¼7.1, para-HePhSO2), 7.64 (d, 1H, J1 e2 ¼12.1, H-1 ), 7.85 (d,
0
0
0
0
0
0
HePhSO2), 7.51 (t, 1H, Jvic¼7.5, para-HePhSO2), 7.68(s, 1H, H-10), 7.73
2H, ortho-HePhSO2, Jvic¼7.1). 13C NMR
d 55.4 (OMe), 66.6 (C-5), 71.1
(d, 2H, Jvic¼7.5, ortho-HePhSO2). 13C NMR
d
28.9 (C-30), 55.9 (OMe),
(C-4), 71.9 (C-6), 72.1, 73.1 (PhCH2O), 73.7 (C-2), 79.8 (C-3), 99.6 (C-
1), 107.5 (C-20), 126.3, 127.3, 128.2, 128.3, 128.4, 128.8, 129.0,
129.5 (CHeAr), 133.1 (CHepara-PhSO2), 138.2, 138.3 (CIVeAr), 143.0
(CIVePhSO2), 161.8 (C-10). IR (film): 3483 (OH), 3064, 3065, 3029,
2925 (CHeAr, ]CH), 1626, 1609 (C]C), 1141 (PhSO2), 1027, 969 (]
CeOR). MS IS m/z¼541.5 [MþH]þ, 558.5 [MþNH4]þ, 563.5
[MþNa]þ, 579.5 [MþK]þ. HRMS: C29H32O8S: calcd 540.1818; found
540.1809.
61.2 (C-6), 69.7 (C-5), 73.8, 75.7 (PhCH2O), 79.8 (C-2, C-3), 82.4 (C-4),
98.6 (C-1), 116.5 (C-50), 117.9 (C-20), 128.1, 128.2, 128.5, 128.8, 128.9,
129.3 (CHeAr), 133.1 (CHepara-PhSO2), 133.8 (C-40), 138.2, 138.4
(CIVeAr), 141.3 (CIVePhSO2), 158.1 (C-10). IR (film): 3485 (OH), 3063,
3031, 2912 (CHeAr, ]CH), 1642 (C]C), 1153 (PhSO2), 997, 915 (]
CeOR). MS IS m/z¼549.5 [MꢀOMe]þ, 598.5 [MþNH4]þ, 603.5
[MþNa]þ. HRMS: C32H36O8S: calcd 580.2131; found 580.2116.
4.3.13. Methyl 2,3-di-O-benzyl-6-O-[(E)-20-(phenylsulfonyl)vinyl]-
-galactopyranoside (17a). Obtained from methyl 2,3-di-O-benzyl-
b
-
4.3.16. Methyl 2,3-di-O-benzyl-4-O-[(E)-20-(phenylsulfonyl)vinyl]-
-mannopyranoside (2b). Obtained as co-product in the above re-
a-
D
D
4,6-O-(2-phenylsulfonyl)ethylidene-
b
-
D
-galactopyranoside
17
action; silica gel column chromatography (petroleum ether/EtOAc
[280557-36-0]1b by quenching with acetic acid; silica gel column
7:3, 65:35, 6:4 then 1:1) afforded compound 2b with 35% yield as
20
chromatography (petroleum ether/EtOAc 7:3, 6:4 then 1:1) affor-
a colourless gum, [
a]
þ23 (c 2.2, CHCl3). 1H NMR
d 3.30 (s, 3H,
D
ded compound 17a with 43% yield as a colourless gum, [
4.5, CHCl3). 1H NMR
a
]
20 ꢀ5 (c
OMe), 3.63e3.82 (m, 5H, H-3, H-4, H-5, H-6a, H-6b), 4.44 (d, 1H,
D
d
3.48 (dd, 1H, J2e3¼9.8, J3e4¼3.2, H-3), 3.48 (s,
J
1e2<0.5, J2e3¼3.6, H-2), 4.42 and 4.49 (2d, AB system, 2H,
3H, OMe), 3.57e3.62 (m, 2H, H-2, H-5), 3.87 (d, 1H, J3e4¼3.2,
4e5<0.5, H-4), 4.05e4.14 (m, 2H, H-6a, H-6b), 4.23 (d, 1H, J1e2¼7.4,
H-1), 4.67 (s, 2H, PhCH2O), 4.69 and 4.86 (2d, AB system, 2H,
Jgem¼11.9, PhCH2O), 4.63 (s, 2H, PhCH2O), 4.70 (s, 1H, J1e2<0.5, H-1),
0
0
0
J
5.81 (d, 1H, J1 e2 ¼11.7, H-2 ), 7.24e7.33 (m, 10H, HeAr), 7.41 (t, 2H,
Jvic¼7.6, meta-HePhSO2), 7.52 (t, 1H, Jvic¼7.6, para-HeAr PhSO2),
0
0
0
0
0
0
Jgem¼11.1, PhCH2O), 5.79 (d, 1H, J1 e2 ¼12.1, H-2 ), 7.22e7.36 (m, 10H,
7.68 (d, 1H, J1 e2 ¼11.7, H-1 ), 7.80 (d, 2H, Jvic¼7.6, ortho-HePhSO2).
HeAr), 7.42e7.55 (m, 3H, meta-, para-HePhSO2), 7.60 (d, 1H,
13C NMR
d 55.5 (OMe), 61.6 (C-6), 70.8 (C-5), 72.2, 73.5 (PhCH2O),
J1 e2 ¼12.1, H-1 ), 7.87 (d, 2H, Jvic¼7.2, ortho-HePhSO2). 13C NMR
74.3, 77.9 (C-3, C-4), 79.7 (C-2), 99.7 (C-1), 108.1 (C-20), 127.3, 128.1,
128.2, 128.3, 128.8, 128.9, 129.5 (CHeAr), 133.1 (CHepara-PhSO2),
137.9, 138.1 (CIVeAr), 142.9 (CIVePhSO2), 162.5 (C-10). IR (film): 3473
(OH), 3064, 3030, 2924 (CHeAr, ]CH), 1625 (C]C), 1141 (PhSO2),
970 (]CeOR). MS IS m/z¼558.5 [MþNH4]þ, 563.5 [MþNa]þ, 579.5
[MþK]þ. HRMS: C29H32O8S: calcd 540.1818; found 540.1804.
0
0
0
d
57.5 (OMe), 67.0 (C-4), 71.8 (C-6), 72.7 (C-5), 73.1, 75.5 (PhCH2O),
79.1 (C-2), 80.5 (C-3), 105.0 (C-1), 107.8 (C-20), 127.3, 128.1, 128.3,
128.4, 128.8, 128.9, 129.6 (CHeAr), 133.3 (CHepara-PhSO2), 138.1,
139.0 (CIVeAr), 142.8 (CIVePhSO2), 161.5 (C-10). IR (film): 3484 (OH),
3064, 3030, 2926, 2870 (CHeAr, ]CH), 1626 (C]C), 1372, 1140
(PhSO2), 998, 960 (]CeOR). MS IS m/z¼558.5 [MþNH4]þ, 563.5
[MþNa]þ. HRMS: C29H32O8S: calcd 540.1818; found 540.1807.
4.3.17. Methyl 2,3-anhydro-6-O-[(E)-20-(phenylsulfonyl)vinyl]-
allopyranoside (18a). Obtained from methyl 2,3-anhydro-4,6-O-(2-
phenylsulfonyl)ethylidene-
-allopyranoside 18 [280557-39-3]1b
a-D-
4.3.14. Methyl 2,3-di-O-benzyl-4-O-[(E)-20-(phenylsulfonyl)vinyl]-
-galactopyranoside (17b). Obtained as co-product in the above
b
-
a-D
D
by quenching with acetic acid; silica gel column chromatography
reaction; silica gel column chromatography (petroleum ether/
(petroleum ether/EtOAc 7:3, 1:1 then 1:4) afforded compound 18a
EtOAc 7:3, 6:4 then 1:1) afforded compound 17b with 26% yield as
with 38% yield as a colourless gum, [
a
]
D
20 þ69 (c 1.5, CHCl3). 1H NMR
20
a colourless gum, [
a]
þ100 (c 4.2, CHCl3). 1H NMR
d
3.54 (s, 3H,
d
3.39 (s, 3H, OMe), 3.49 (d, 1H, J2e3¼3.2, J3e4<0.5, H-3), 3.57 (t, 1H,
D
OMe), 3.35e3.62 (m, 4H, H-2, H-3, H-5, H-6b), 3.77 (dd, 1H,
J5e6a¼5.8, J6ae6b¼10.0, H-6a), 4.30 (d, 1H, J1e2¼6.1, H-1), 4.40 (d, 1H,
J3e4¼2.1, J4e5<0.5, H-4), 4.61 and 4.73 (2d, AB system, 2H, Jgem¼11.3,
J1e2¼J2e3¼3.2, H-2), 3.80e3.92 (m, 2H, H-4, H-5), 4.04 (dd, 1H,
J5e6b¼5.1, J6ae6b¼11.3, H-6b), 4.15 (d, 1H, J5e6a<0.5, J6ae6b¼11.3, H-
0
0
0
6a), 4.88 (d, 1H, J1e2¼3.2, H-1), 5.79 (d, 1H, J1 e2 ¼12.1, H-2 ), 7.51 (t,

ꢀ
F. Chery et al. / Tetrahedron 68 (2012) 544e551
550
2H, Jvic¼7.2, meta-HePhSO02), 7.56 (t, 1H, Jvic¼7.2, para-HePhSO2),
[MþNH4]þ, 493.5 [MþNa]þ, 959.0 [2MþNH4]þ. HRMS:
0
0
7.60 (d, 1H, J1 e2 ¼12.1, H-1 ), 7.87 (d, 2H, Jvic¼7.2, ortho-HePhSO2).
C22H34O7SSi: calcd 470.1795; found 470.1780.
13C NMR
d 54.2 (C-3), 55.9 (C-2), 56.3 (OMe), 65.8, 68.1 (C-4, C-5),
71.8 (C-6), 95.0 (C-1), 109.4 (C-20), 128.9 (CHeortho-PhSO2), 131.2
(CHemeta-PhSO2), 134.9 (CHepara-PhSO2), 144.3 (CIVePhSO2),
163.1 (C-10). IR (film): 3065, 2958, 2931 (CHeAr, ]CH), 1625, 1616
(C]C), 1193 (PhSO2), 985, 963 (]CeOR). MS IS m/z¼311.0
[MꢀOMe]þ, 343.0 [MþH]þ, 360.0 [MþNH4]þ, 365.0 [MþNa]þ.
HRMS: C15H18O7S: calcd 342.0773; found 342.0780.
4.3.21. 1,2-O-Isopropylidene-6-O-[(E)-20-(phenylsulfonyl)vinyl]-
glucofuranose (19a). Obtained from 1,2-O-isopropylidene-5,6-O-
a-D-
(2-phenylsulfonyl)ethylidene-a-D-glucofuranose 19 [280557-43-
9]1b by quenching with acetic acid; silica gel column chromatog-
raphy (petroleum ether/EtOAc 7:3, 6:4 then 1:1) afforded com-
20
pound 19a with 43% yield as a colourless gum, [
a]
ꢀ5 (c 2.5,
D
CHCl3). 1H NMR
d
1.28 and 1.45 (2s, 6H, Me2C), 3.97 (dd, 1H,
4.3.18. Methyl 2,3-anhydro-6-O-tert-butyldimethylsilyl-4-O-[(E)-20-
(phenylsulfonyl)vinyl]-a-D-allopyranoside (18b). Isolated in 29%
yield as co-product of the reaction after selective 6-O-silylation.
J5e6b¼6.4, J6ae6b¼10.6, H-6b), 4.06 (dd, 1H, J3e4¼2.7, J4e5¼7.7, H-4),
4.07 (dd, 1H, J5e6a¼2.8, J6ae6b¼10.6, H-6a), 4.21 (ddd, 1H, J4e5¼7.7,
J5e6a¼2.8, J5e6b¼6.4, H-5), 4.35 (d, 1H, J2e3<0.5, J3e4¼2.7, H-3),
20
Colourless gum, [
a
]
þ116 (c 3, CHCl3). 1H NMR
d
0.01 (s, 6H,
0
D
0
0
4.51 (d, 1H, J1e2¼3.6, J2e3<0.5, H-2), 5.79 (d, 1H, J1 ,2 ¼12.1, H-2 ),
Me2Si), 0.87 (s, 9H, t-BuSi), 3.41 (s, 3H, OMe), 3.49 (d, 1H, J2e3¼3.0,
5.90 (d, 1H, J1e2¼3.6, H-1), 7.51 (t, 2H, Jvic¼7.0, meta-HePhSO2),
J
3e4<0.5, H-3), 3.52 (t, 1H, J1e2¼J2e3¼3.0, H-2), 3.65 (dd, 1H,
0
0
0
7.56 (t, 1H, Jvic¼7.0, para-HePhSO2), 7.63 (d, 1H, J1 ,2 ¼12.1, H-1 ),
7.83 (d, 2H, Jvic¼7.0, ortho-HePhSO2). 13C NMR
d 27.7, 27.9 (Me2C),
J5e6b¼1.6, J6ae6b¼11.7, H-6b), 3.73 (d, 1H, J5e6a<0.5, J6ae6b¼11.7, H-
6a), 3.80 (dd, 1H, J4e5¼9.4, J5e6a<0.5, J5e6b¼1.6, H-5), 4.48 (d, 1H,
68.9 (C-5), 75.0 (C-6), 75.9 (C-3), 80.5 (C-4), 86.2 (C-2), 106.2 (C-1),
108.2 (C-20), 112.0 (Me2C), 128.1 (CHeortho-PhSO2), 130.4
(CHemeta-PhSO2), 134.2 (CHepara-PhSO2), 142.0 (CIVePhSO2),
162.2 (C-10). IR (film): 3474 (OH), 3071, 2987, 2936 (CHeAr, ]CH),
1626, 1609 (C]C), 1383, 1146 (PhSO2), 1017, 957 (]CeOR). MS IS
m/z¼404.5 [MþNH4]þ, 409.5 [MþNa]þ, 425.5 [MþK]þ. HRMS:
C17H22O8S: calcd 386.1035; found 386.1021.
J
3e4<0.5, J4e5¼9.4, H-4), 4.87 (d, 1H, J1e2¼3.0, H-1), 5.94 (d, 1H,
0
0
0
J1 e2 ¼11.9, H-2 ), 7.46 (t, 2H, Jvic¼7.0, meta-HePhSO02), 7.54 (t, 1H,
0
0
Jvic¼7.0, para-HePhSO2), 7.62 (d, 1H, J1 e2 ¼11.9, H-1 ), 7.85 (d, 2H,
Jvic¼7.0, ortho-HePhSO2). 13C NMR
d
0.01 (2*Me), 18.7 (CIVet-Bu),
26.3 (3*Me), 51.3 (C-3), 55.4 (C-2), 56.1 (OMe), 61.6 (C-6), 67.3 (C-5),
76.5 (C-4), 94.7 (C-1), 109.6 (C-20), 127.3 (CHeortho-PhSO2), 129.6
(CHemeta-PhSO2), 132.9 (CHepara-PhSO2), 142.6 (CIVePhSO2),
160.3 (C-10). IR (film): 3070, 2955, 2928 (CHeAr, ]CH), 1628, 1606
(C]C), 1183 (PhSO2), 975, 965 (]CeOR). MS IS m/z¼425.5 [M-
OMe]þ, 457.5 [MþH]þ, 474.5 [MþNH4]þ, 479.5 [MþNa]þ. HRMS:
C21H32O7SSi: calcd 456.1638; found 456.1619.
4.3.22. 1,2-O-Isopropylidene-5-O-[(E)-20-(phenylsulfonyl)vinyl]-
a-D-
glucofuranose (19b). Obtained as co-product in the above reaction;
silica gel column chromatography (petroleum ether/EtOAc 7:3, 6:4
then 1:1) afforded compound 19b with 44% yield as a colourless
gum, [
a
]
20 þ34 (c 1.2, CHCl3). 1H NMR
d 1.29 and 1.46 (2s, 6H, Me2C),
D
4.3.19. 1,2-O-Isopropylidene-5-O-[(E)-20-(phenylsulfonyl)vinyl]-
xylofuranose (4a). Obtained from 1,2-O-isopropylidene-3,5-O-(2-
phenylsulfonyl)ethylidene-
-xylofuranose 4 [330151-22-9]1b by
a-D-
3.79 (dd, 1H, J5e6b¼5.9, J6ae6b¼12.6, H-6b), 3.99 (dd, 1H, J5e6a¼3.0,
J6ae6b¼12.6, H-6a), 4.19 (dd,1H, J3e4¼2.8, J4e5¼7.8, H-4), 4.20 (d,1H,
a-D
J
2e3<0.5, J3e4¼2.8, H-3), 4.44 (ddd, 1H, J4e5¼7.8, J5e6a¼2.8,
quenching with acetic acid; silica gel column chromatography
(petroleum ether/EtOAc 6:4 then 1:1) afforded compound 4a with
J5e6b¼5.9, H-5), 4.51 (d, 1H, J1e2¼3.4, J2e3<0.5, H-2), 5.89 (d, 1H,
0
0
0
J1 ,2 ¼12.1, H-2 ), 5.90 (d, 1H, J1e2¼3.4, H-1), 7.50 (t, 2H, Jvic¼7.2,
meta-HePhSO2), 7.56 (t, 1H, Jvic¼7.2, para-HePhSO2), 7.57 (d, 1H,
88% yield as a colourless gum, [
a
]
20 ꢀ6 (c 2, CHCl3). 1H NMR
d 1.27
D
and 1.45 (2s, 6H, Me2C), 2.99 (s, 1H, OH), 4.05 (dd, 1H, J4e5b¼6.6,
J5ae5b¼10.6, H-5b), 4.13 (dd, 1H, J4e5a¼4.9, J5ae5b¼10.6, H-5a), 4.22
(d, 1H, J2e3<0.5, J3e4¼2.3, H-3), 3.34e3.39 (m, 1H, H-4), 4.48 (d,
J1 ,2 ¼12.1, H-1 ), 7.86 (d, 2H, Jvic¼7.2, ortho-HePhSO2). 13C NMR
0
0
0
d
26.5, 27.1 (Me2C), 62.9 (C-6), 74.2 (C-3), 78.9 (C-4), 82.5 (C-5), 85.4
(C-2), 105.3 (C-1), 108.0 (C-20), 112.5 (Me2C), 127.2 (CHeortho-
PhSO2), 129.6 (CHemeta-PhSO2), 133.3 (CHepara-PhSO2), 142.4
(CIVePhSO2), 162.2 (C-10). IR (film): 3462 (OH), 3069, 2987, 2935
(CHeAr, ]CH), 1625 (C]C), 1384, 1140 (PhSO2), 954 (]CeOR). MS
IS m/z¼404.5 [MþNH4]þ, 409.5 [MþNa]þ, 425.5 [MþK]þ. HRMS:
C17H22O8S: calcd 386.1035; found 386.1025.
0
0
0
1H, J1e2¼3.6, J2e3<0.5, H-2), 5.77 (d, 1H, J1 ,2 ¼12.1, H-2 ), 5.91 (d,
1H, J1e2¼3.6, H-1), 7.46e7.57 (m, 3H, meta, para-HePhSO2), 7.58
(d, 1H, J1 ,2 ¼12.1, H-1 ), 7.83 (d, 2H, Jvic¼7.5, ortho-HePhSO2). 13C
0
0
0
NMR
d 26.6, 27.1 (CH3), 70.3 (C-5), 75.1 (C-3), 78.4 (C-4), 85.6
(C-2), 105.3 (C-1), 107.5 (C-20), 112.3 (Me2C), 127.3 (CHeortho-
PhSO2), 129.7 (CHemeta-PhSO2), 133.4 (CHepara-PhSO2), 142.3
(CIVePhSO2), 161.3 (C-10). IR (film): 3475 (OH), 3072, 2988 (CHeAr,
]CH), 1627, 1610 (C]C), 1142 (PhSO2), 1014 (]CeOR). MS IS
m/z¼374.5 [MþNH4]þ, 379.5 [MþNa]þ. HRMS: C16H20O7S: calcd
356.0930; found 356.0935.
4.3.23. 3-O-Benzyl-1,2-O-isopropylidene-6-O-[(E)-20-(phenyl-
sulfonyl)vinyl]-a-D-glucofuranose (20a). Obtained from 3-O-benzyl-
1,2-O-isopropylidene-5,6-O-(2-phenylsulfonyl)ethylidene-a-D-glu-
cofuranose 20 [280557-44-0]1b by quenching with acetic acid; sil-
ica gel column chromatography (petroleum ether/EtOAc 7:3, 6:4
then 1:1) afforded compound 20a with 50% yield as a colourless
4.3.20. 5-O-tert-Butyldimethylsilyl-1,2-O-isopropylidene-3-O-[(E)-
20-(phenylsulfonyl)vinyl]-
a-D-xylofuranose (4b). Isolated in 7% yield
as co-product of the reaction after selective 5-O-silylation. Col-
gum, [
a
]
20 ꢀ23 (c 6.9, CHCl3). 1H NMR
d 1.28 and 1.43 (2s, 6H, Me2C),
D
20 þ100 (c 2, CHCl3). 1H NMR
d 0.01 (s, 3H, TBDMS),
2.99 (s, 1H, OH), 3.86 (d, 1H, J5e6b¼6.2, J6ae6b¼10.2, H-6b), 4.00 (d,
1H, J5e6a<0.5, J6ae6b¼10.2, H-6a), 4.08e4.13 (m, 2H, H-3, H-4),
4.17e4.27 (m, 1H, H-5), 4.61 (d, 1H, J1e2¼3.6, J2e3<0.5, H-2), 4.53
and 4.67 (2d, 0 AB system, 2H, Jgem¼11.9, PhCH2O), 5.70 (d, 1H,
ourless gum, [
a
]
D
0.03 (s, 3H, Me2Si), 0.83 (s, 9H, t-BuSi), 1.31 and 1.51 (2s, 6H, Me2C),
3.72 (t, 1H, J4e5b¼J5ae5b¼10.0, H-5b), 3.85 (dd, 1H, J4e5a¼5.3,
J5ae5b¼10.0, H-5a), 4.32 (ddd, 1H, J3e4¼2.9, J4e5a¼5.3, J4e5b¼10.0,
H-4), 4.40 (d, 1H, J2e3<0.5, J3e4¼2.9, H-3), 4.52 (d, 1H, J1e2¼3.8,
0
0
J1 ,2 ¼12.1, H-2 ), 5.87 (d, 1H, J1e2¼3.6, H-1), 7.25e7.31 (m, 5H,
0
0
0
HeAr), 7.43e7.53 (m, 3H, meta-, para-HePhSO2), 7.58 (d, 1H,
J
2e3<0.5, H-2), 5.88 (d, 1H, J1 ,2 ¼12.1, H-2 ), 5.89 (d, 1H, J1e2¼3.8, H-
J1 ,2 ¼12.1, H-1 ), 7.83 (d, 2H, Jvic¼7.4, ortho-HePhSO2). 13C NMR
0
0
0
0
0
1), 7.49e7.63 (m, 3H, meta, para-PhSO2), 7.55 (d, 1H, J1 ,2 ¼12.1, H-
10), 7.87 (d, 2H, Jvic¼7.2, ortho-HePhSO2). 13C NMR
d
25.9e27.0
d
26.6, 27.2 (Me2C), 67.6 (C-5), 72.5 (PhCH2O), 74.3 (C-6), 79.7, 81.8
(C-3, C-4), 82.4 (C-2), 105.6 (C-1), 107.4 (C-20), 112.2 (Me2C), 127.3,
128.0, 128.3, 129.1, 129.6 (CHeAr), 133.2 (CHepara-PhSO2), 137.5
(CIVeAr), 142.6 (CIVePhSO2), 161.2 (C-10). IR (film): 3442 (OH),
3020 (CHeAr, ]CH), 1628, 1611 (C]C), 1144, 1385 (PhSO2), 1027,
963 (]CeOR). MS IS m/z¼477.5 [MþH]þ, 494.5 [MþNH4]þ, 499.5
(Me2C, TBDMS), 59.4 (C-5), 79.7 (C-4), 82.4 (C-2), 84.5 (C-3), 105.4
(C-1), 109.3 (C-20), 112.8 (Me2C), 127.4 (CHeortho-PhSO2), 129.6
(CHemeta-PhSO2), 133.4 (CHepara-PhSO2), 142.5 (CIVePhSO2),
159.6 (C-10). IR (film): 2930, 2857 (CHeAr, ]CH), 1629, 1609 (C]C),
1145 (PhSO2), 1022 (]CeOR). MS IS m/z¼471.5 [MþH]þ, 488.5

ꢀ
F. Chery et al. / Tetrahedron 68 (2012) 544e551
551
[MþNa]þ, 515.5 [MþK]þ. HRMS: C24H28O8S: calcd 476.1505; found
PhSO2), 142.7 (CIVePhSO2), 161.3 (C-10). IR (film): 3075, 2988, 2932
(CHeAr, ]CH), 1627 (C]C), 1398, 1142 (PhSO2), 955 (]CeOR). MS
IS m/z¼371.0 [MþH]þ, 388.0 [MþNH4]þ, 393.0 [MþNa]þ, 409.0
[MþK]þ. HRMS: C17H22O7S: calcd 370.1086; found 370.1078.
476.1502.
4.3.24. 3-O-Benzyl-1,2-O-isopropylidene-5-O-[(E)-20-(phenyl-
sulfonyl)vinyl]-a-D-glucofuranose (20b). Obtained as co-product in
the above reaction; silica gel column chromatography (petroleum
ether/EtOAc 7:3, 6:4 then 1:1) afforded compound 20b with 14%
Acknowledgements
yield as a colourless gum, [
a
]
20 ꢀ6 (c 3.2, CHCl3). 1H NMR
d 1.29 and
D
ꢀ
ꢀ
The authors wish to thank the Universite d’Orleans, the Uni-
1.46 (2s, 6H, Me2C), 3.76 (d, 1H, J5e6b¼5.3, J6ae6b¼12.6, H-6b), 3.93
(dd, 1H, J5e6a¼2.6, J6ae6b¼12.6, H-6a), 3.96 (d, 1H, J2e3<0.5,
J3e4¼2.8, H-3), 4.26 (dd, 1H, J3e4¼2.8, J4e5¼8.9, H-4), 4.38 (ddd, 1H,
J4e5¼8.9, J5e6a¼2.6, J5e6b¼5.3, H-5), 4.50 and 4.58 (2d, AB system,
2H,Jgem¼11.9, PhCH2O), 4.61 (d, 1H, J1e2¼3.2, J2e3<0.5, H-2), 5.85 (d,
ꢁ
ꢁ
versita Ca Foscari di Venezia, the French MENRT and EGIDE for
grants (F.C., E.C.).
References and notes
0
0
0
1H, J1 ,2 ¼11.7, H-2 ), 5.87 (d, 1H, J1e2¼3.2, H-1), 7.26e7.41 (m, 5H,
€
1. (a) De Lucchi, O.; Pasquato, L.; Rollin, P.; Tatibouet, A. 1,2-Bis(phenylsulfonyl)
HeAr), 7.46 (t, 2H, Jvic¼7.5, meta-HePhSO2), 7.53 (t, 1H, Jvic¼7.5,
ethylene. e-EROS Encyclopedia of Reagents for Organic Synthesis; John Wiley &
0
0
0
para-HePhSO2), 7.57 (d, 1H, J1 ,2 ¼11.7, H-1 ), 7.99 (d, 2H, Jvic¼7.5,
ꢀ
Sons: 2005; (b) Chery, F.; De Lucchi, O.; Cossu, S.; Rollin, P. Synthesis 2001,
ortho-HePhSO2). 13C NMR
d 26.6, 27.1 (Me2C), 62.9 (C-6), 72.5
286e292.
€
2. (a) Chevalier-du Roizel, B.; Cabianca, E.; Rollin, P.; Sinay, P. Tetrahedron 2002, 58,
9579e9583; (b) Cabianca, E.; Tatibouet, A.; Rollin, P. Pol. J. Chem. 2005, 79,
(PhCH2O), 78.3 (C-4), 81.3 (C-3), 81.7, 81.8 (C-2, C-5), 105.6 (C-1),
108.7 (C-20), 112.5 (Me2C), 127.2, 127.6, 128.4, 129.1, 129.6 (CHeAr),
133.2 (CHepara-PhSO2), 137.4 (CIVeAr), 140.9 (CIVePhSO2), 161.2 (C-
10). IR (film): 3493 (OH), 3068, 3020, 2990 (CHeAr, ]CH), 1625,
1610 (C]C), 1384 (PhSO2), 1024, 983 (]CeOR). MS IS m/z¼477.5
[MþH]þ, 494.5 [MþNH4]þ, 499.5 [MþNa]þ, 515.5 [MþK]þ. HRMS:
C24H28O8S: calcd 476.1505; found 476.1496.
€
€
ꢀ
ꢀ
317e322; (c) Uttaro, J. P.; Uttaro, L.; Tatibouet, A.; Rollin, P.; Mathe, C.; Perigaud,
C. Tetrahedron Lett. 2007, 48, 3851e3854; (d) Fernandes, A.; Dell0Olmo, M.;
€
Tatibouet, A.; Imberty, A.; Philouze, C.; Rollin, P. Tetrahedron Lett. 2008, 49,
3484e3488.
3. Simpkins, N. S. In Sulphones in Organic Synthesis; Baldwin, J. E., Magnus, P. D.,
Eds.; Pergamon: Oxford, 1993; pp 100e182.
4. (a) Julia, M.; Uguen, D. Bull. Soc. Chim. Fr. 1976, 513e518; (b) Julia, M.; Blasioli, C.
Bull. Soc. Chim. Fr. 1976, 1941e1946.
5. Trost, B. M.; Lynch, J.; Renaut, P.; Steinman, D. H. J. Am. Chem. Soc. 1986, 108,
284e291.
6. Achmatowicz, B.; Baranowska, E.; Daniewski, A. R.; Pankowski, J.; Wicha, J.
Tetrahedron 1988, 44, 4989e4998.
7. Binns, M. R.; Haynes, R. K.; Katsifis, A. G.; Schober, P. A.; Vonwiller, S. C. J. Org.
Chem. 1989, 54, 1960e1968.
4.3.25. 3-Deoxy-1,2-O-isopropylidene-6-O-[(E)-20-(phenylsulfonyl)
vinyl]-a-D-glucofuranose (21a). Obtained from 3-deoxy-1,2-O-iso-
propylidene-5,6-O-(2-phenylsulfonyl)ethylidene-a-D-glucofur-
anose 21 [280557-42-8]1b by quenching with acetic acid; silica gel
8. See for example Bonete, P.; Najera, C. Tetrahedron 1995, 51, 2763e2776 and
references cited.
column chromatography (petroleum ether/EtOAc 1:1) afforded
compound 21a with 82% yield as a colourless gum, [
a
]
2029 þ2 (c
D
9. Simpkins, N. S. Tetrahedron Lett. 1987, 28, 989e992.
10. Ballini, R.; Bosica, G.; Cossu, S.; De Lucchi, O.; Peluso, P. Tetrahedron 2001, 57,
4461e4465.
11. Grossert, J. S. In The Chemistry of Sulphones and Sulphoxides; Patai, S., Rappoport,
Z., Stirling, C. J. M., Eds.; John Wiley & Sons: Chichester, UK, 1988, Chapter 20.
12. (a) Chandrasekhar, S.; Srinivas, C.; Srihari, P. Synth. Commun. 2003, 33,
895e902; (b) Evans, P. A.; Manangan, T. J. Org. Chem. 2000, 65, 4523e4528; (c)
6.8, CHCl3). 1H NMR
d
1.29 and 1.46 (2s, 6H, Me2C), 1.81 (ddd, 1H,
J2e3b¼3.6, J3be4¼10.6, J3ae3b¼13.4, H-3b), 2.09 (dd, J2e3a<0.5,
J3ae4¼4.5, J3ae3b¼13.4, H-3a), 3.84 (dd,1H, J5e6b¼7.2, J6ae6b¼11.1, H-
6b), 3.96e4.02 (m, 2H, H-5, H-6a), 4.17 (dd, 1H, J3ae4¼4.5,
J3be4¼10.6,
J
4e5<0.5, H-4), 4.72 (t, 1H, J1e2¼3.6,
J2e3a<0.5,
0
ꢀ
€
Chery, F.; Desroses, M.; Tatibouet, A.; De Lucchi, O.; Rollin, P. Tetrahedron 2003,
59, 4563e4572.
0
J2e3b¼3.6, H-2), 5.77 (d, 1H, J1e2¼3.6, H-1), 5.78 (d, 1H, J1 ,2 ¼12.1, H-
20), 7.50 (t, 2H, Jvic¼7.2, meta-HePhSO2), 7.60 (t, 1H, Jvic¼7.2, para-
13. Padwa, A.; Bullock, W. H.; Dyszlewski, A. D.; McCombie, S. W.; Shankar, B. B.;
Ganguly, A. K. J. Org. Chem. 1991, 56, 3556e3564.
14. Eisch, J. J.; Galle, J. E. J. Org. Chem. 1979, 44, 3279e3280.
0
0
0
HePhSO2), 7.61 (d, 1H, J1 ,2 ¼12.1, H-1 ), 7.85 (d, 2H, Jvic¼7.2, ortho-
HePhSO2). 13C NMR
d 26.4, 27.1 (Me2C), 34.6 (C-3), 70.7 (C-5), 73.6
15. Kleijn, H.; Vermeer, P. J. Organomet. Chem. 1986, 302, 1e4.
(C-6), 78.2 (C-4), 80.3 (C-2), 105.3 (C-1), 107.7 (C-20), 111.8 (Me2C),
127.2 (CHeortho-PhSO2), 129.6 (CHemeta-PhSO2), 133.2 (CHepara-
ꢀ
€
16. Chery, F.; Pillard, C.; Tatibouet, A.; De Lucchi, O.; Rollin, P. Tetrahedron 2006, 62,
5141e5151.