Chemoselective deprotection of acid labile primary hydroxyl protecting groups under CBr4-photoirradiation conditions

Article abstract of DOI:10.1016/j.tet.2004.09.095

The CBr₄-photoirradiation in methanol generates a controlled source of HBr, which can chemoselectively deprotect commonly used hydroxyl-protecting groups in saccharides and nucleosides, such as tert-butyldimethylsilyl, isopropylidene, benzylidene and triphenyl ethers in the presence of other acid-labile functional groups. Graphical Abstract.

Full text of DOI:10.1016/j.tet.2004.09.095

Tetrahedron 60 (2004) 11465–11475
Chemoselective deprotection of acid labile primary hydroxyl
protecting groups under CBr4-photoirradiation conditions
b
b
c
Ming-Yi Chen,a, Laxmikant N. Patkar, Kuo-Cheng Lu, Adam Shih-Yuan Lee
*
and Chun-Cheng Linb,d,
*
aDepartment of General Education, National Taipei College of Nursing, Taipei 112, Taiwan, ROC
bInstitute of Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan, ROC
cDepartment of Chemistry, Tamkang University, Tamsui 251, Taiwan, ROC
dDepartment of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC
Received 14 May 2004; revised 14 September 2004; accepted 17 September 2004
Abstract—The CBr4-photoirradiation in methanol generates a controlled source of HBr, which can chemoselectively deprotect commonly
used hydroxyl-protecting groups in saccharides and nucleosides, such as tert-butyldimethylsilyl, isopropylidene, benzylidene and triphenyl
ethers in the presence of other acid-labile functional groups.
q 2004 Elsevier Ltd. All rights reserved.
1. Introduction
successfully used to cleave acetals/ketals,4b tetrahydropyranyl
ethers,4a trialkylsilylethers,5 methoxymethylethers, methoxy-
ethoxymethyl ethers,6 trityl ethers,7 p-methoxybenzyl
(PMB)8 and b-(trimethylsilyl)ethoxymethyl ethers9 in only
catalytic amounts, but heating in methanol to the reflux
temperature is required. The success of this deprotection
protocol depends on the in situ generation of HBr, which
provides mild but sufficiently anhydrous and acidic reaction
conditions.4d,6 This fact motivated us to investigate the use of
this protocol in carbohydrate and nucleoside chemistry,
eventuallyleadingtoidentifyingthemildreactionconditions.3
A protective and deprotective strategy is a critical part of
many synthetic scheme that involve carbohydrate and
nucleoside chemistry. According, an impressive array of
protective groups have been developed to protect the
hydroxyl group, along with methods for removing them.1
Additionally, the efficient synthesis of polyfunctional target
molecules relies on the development of a protection–
deprotection strategy with fewer steps than implemented
at present. This, in principle, can be achieved using a single
group to protect all functional groups and then chemoselec-
tively deprotecting the desired functional group, rather than
using different groups to protect each functional group and
then deprotecting them individually.2 The development of
chemoselectively deprotecting reagents is critical to the
success of this strategy. Our earlier results showed that a
catalytic amount of carbon tetrabromide under photoirra-
diation in methanol can chemoselectively deprotect tert-
butyldimethylsilyl (TBDMS), isopropylidenyl, benzylide-
nyl and triphenylmethyl groups on the primary hydroxyl
groups of saccharides and nucleosides.3 This study reports
the scope of this mild and efficient protocol.
Among the various protecting groups, commonly used
groups, such as TBDMS, acetonide and trityl, were used in
this deprotection study. Silyl ethers such as TBDMS are
particularly useful because they are stable in the presence of
various reagents and conditions.10 TBDMS ethers can be
deprotected under various conditions, including the
prescence of fluoride ions, protic acids and Lewis acids.11–13
In other cases the primary TBDMS group can be selectively
removed under acidic conditions if the secondary silyl group
is sterically hindered.14,15 However, this procedure normally
exhibits poor selectivity. Apart from silyl ethers, acetonide
has been used widely in carbohydrate chemistry to
selectively mask the hydroxyls of many sugars. Although
normal acidic catalysts such as HCl, HBr, TFA and AcOH
have been satisfactory reagents1,4b,16 for selectively hydro-
lyzing primary–secondary hydroxyl groups in simple
diacetonide derivatives, their strong acidity and free protons
make them undesirable hydrolyzing derivatives with acid-
sensitive groups.17
CBr4 has been used as a catalyst and reagent to perform
various interesting transformations.4 It has also been
Keywords: CBr4-photoirradiation; Deprotection.
* Corresponding authors. Address: National Taipei College of Nursing No.
365, Ming Road, Pei Tou, Taipei 112, Taiwan, ROC. Tel.: C886 2
28227101; fax: 886 2 28264238; e-mail addresses: mingyi@ntcn.edu.tw;
cclin@chem.sinica.edu.tw
0040–4020/$ - see front matter q 2004 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2004.09.095

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M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
Triphenylmethyl (trityl) ethers are also extensively used as
selective protecting groups for primary alcohols, particu-
larly in carbohydrate and nucleoside chemistry, but few
procedures exist for selectively cleaving them.18 Trityl
ethers are generally cleaved under strong protic or Lewis
acid conditions, such as in formic acid, 80% acetic acid,
mineral acids, zinc bromide, trifluoro acetic acid, iodine–
methanol and BCl3.7,18 Some methods of detritylation under
mild conditions have been reported to avoid the cleavage of
glycosidic bond and the hydrolysis of acetate.18 Numerous
such methods suffer from the requirement of the use of
strongly acidic conditions, incompatibility with other acid
sensitive groups, unsatisfactory yields, corrosive/expensive
reagents, longer reaction times and the need for anhydrous
conditions.18
in excellent yields (71–94%) by treatment with a catalytic
amount of CBr4 in methanol under photochemical reaction
conditions.3 The results in Table 1 indicate that other
protecting groups on saccharides affected the extent of
deprotecting rates. When an anomeric hydroxyl group was
protected as methyl ether, the rate of desilylation of the
primary silyl ether normally exceeded faster than other
types of protecting groups on anomeric center (Table 1,
entries 3 and 7). Interestingly, the presence of the free
hydroxyl group near the primary silyl ether accelerated the
deprotection (Table 1, entry 2 and 11). Notably, no silyl
group migration was observed in any cases.
Various substrates 7a–d with primary and secondary
TBDMS groups were prepared20 and their cleavage
investigated to elucidate the utility of the CBr4/MeOH
photoirradiation conditions for deprotecting TBDMS-
protected nucleotides (Table 2, entries 1–4). In the presence
of the amino group of adenosine 7c and guanosine 7d, only
moderate yields were obtained after a reaction over 3 days
(62 and 54%, respectively) even when the amount of CBr4
was increased to 50% mole equivalent. In the presence of
basic amine on the nucleoside base, the base is expected to
trap the catalytic amount of HBr, making it unavailable for
deprotection. Contrary to this expectation, however, the
deprotection of primary TBDMS in nucleosides proceeded
smoothly.
Here, the CBr4/MeOH system was applied to cleave
selectively tert-butyldimethylsilyl, isopropylidene acetals,
benzylidine and trityl groups in carbohydrate and nucleo-
side chemistry.
2. Results and discussion
2.1. Deprotection of tert-butyldimethylsilyl ethers
Table 1 presents the results of our initial investigation of the
regioselective deprotection of primary TBDMS ether in the
presence of secondary TBDMS ethers. The primary
TBDMS ethers of pyranose sugar,19 1, 3 and 5, are removed
An interesting application of this method was demonstrated
by the synthesis of sialic acid derivatives with a free primary
Table 1. Selective deprotection of TBDMS ethers with 5 mol% CBr4/MeOH
Entry
Substratea
Product
Timeb (h)
Yield (%)c
2
1
R1
R2
R3
R4
1
2
3
4
5
6
7
8
9
b-SPh-p-Me
b-SPh-p-Me
a-Ome
OTBDMS
OTBDMS
OTBDMS
OTBDMS
Obn
OTBDMS
OTBDMS
OTBDMS
OTBDMS
OBn
OTol
OBn
OBz
OTBDMS
OTBDMS
OH
2a
2b
2c
2d
2e
2f
2g
2h
2i
20
1
4
28
12
39
5
12
20
75
87
94
90
93
71
85
89
90
OTBDMS
OTBDMS
OTBDMS
OTBDMS
OTBDMS
OTBDMS
OTBDMS
a-All
b-SPh-p-Me
b-SPh-p-Me
a-Ome
b-SPh-p-Me
a-SePh
OTolb
Obn
N3
N3
3
4
10
11
12
13
14
15
16
b-SPh-p-Me
b-SPh-p-Me
a-Ome
b-SPh-p-Me
b-SPh-p-Me
b-SPh-p-Me
OTBDMS
OTBDMS
OTBDMS
Obn
Otol
NHTroc
OTBDMS
OTBDMS
OTBDMS
OBn
OTol
OTBDMS
OTBDMS
OH
OTBDMS
OTBDMS
OTBDMS
OTBDMS
4a
4b
4c
4d
4e
4f
28
2
23
19
10
6
83
95
87
90
92
82
83
13
5
6
a TBDMS, tert-butyldimethylsilyl; Tol, p-methylbenzoyl; All, allyl; Troc, 2,2,2-trichloroethoxycarbonyl.
b Irradiated for 0.5 h then stirred at room temperature.
c The isolated yield after chromatographic purification.

M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
Table 2. Selective deprotection of TBDMS-protected nucleotides with Table 3. Deprotection of isopropylidene from furanose substrates
5 mol% CBr4/MeOH
11467
Entry
Substrate
Product
Time Yield
(h)a
(%)b
R
Reaction time (h)a
Yield (%)b
a
b
Hc
19
36
95
86
7
8
RZTBDMS
RZH
c
d
e
f
Ac
Bz
Bn
24
24
48
42
89
82
84
85
R0
B
1
2
3
4
7a
7b
7c
7d
Thymine
Uracil
Adenine
H
8a
8b
8c
8d
68
68
72
72
85
92
OTBDMS
OTBDMS
62 (33)c
54 (43)c
Guanosine OTBDMS
a Irradiated for 0.5 h then stirred at room temperature.
b The isolated yield after chromatographic purification.
g
h
i
35
48
45
83
88
81
c The number in parenthesis indicates the yield of recovery of the starting
material.
hydroxyl group in the C-9 position (Scheme 1). Sialic acids
are the terminal sugars of various glycoproteins and
glycolipids and participate in masking cell surface antigens,
bacterial cell surface activity, cell-to-cell recognition and
mitogenic–receptor activity with some lectins.21 Therefore,
the synthesis of analogs of sialic acids has attracted
significant interest in studies of relationships between the
structure and function and their inhibitory activity.22 Access
to these synthetic analogs depends primarily on the use of
appropriate protection–deprotection schemes, since the
sialic acid has many hydroxyl groups. As shown in
Scheme 1, sialic acid derivative 9, protected as silyl ether
TBDMS
a Irradiated for 0.5 h then stirred at room temperature.
b The isolated yield after chromatographic purification.
c
was also deprotected to get
in 15 h (90%).
at positions C-4, 7, 8 and 9 underwent the optimized
deprotection protocol, producing compound 10 in very high
yield. Similarly, compounds 11a and 11b gave satisfactory
yields of 12a and 12b. Compounds 12a and 12b were
Scheme 1.

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M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
Table 4. Deprotection of isopropylidene and benzylidene groups from saccharides with 5 mol% CBr4
Entry
1
Substratea
Time (h)b
Product
Yield (%)c
22
8
23
86
2
3
24
26
5
3
25
27
93
92
4
5
6
28
30
32
43
36
36
29
31
72
62
C
33a
33b
70
(4:1)
7d
8
34
36
41
32
35
37
83
86
a Troc, 2,2,2-trichloroethoxycarbonyl; Ms, methanesulfonyl; TBDMS, tert-butyldimethylsilyl.
b Irradiated for 0.5 h then stirred at room temperature.
c The isolated yield after chromatographic purification.
d Cosolvent was used to dissolve the substrate (CH3OH/CH2Cl2Z1:1).
subjected to the standard acetylation protocol to yield
compound 13a and 13b, confirming that the C-9 hydroxy
group had indeed undergone deprotection. The sulfation of
12a and 12b in DMF at 50 8C with SO3/Et3N gave the
sulfated derivatives 14a (75%) and 14b (87%). Notably, the
TBDMS protecting group at C-4 position of 12a was
cleaved under sulfation conditions. The deprotection of C-4
TBDMS was further verified by acetlyation of 14a to give
15a. Consistent with the above results, compound 17 was
obtained from 16. Interestingly, the substituent of amine
function group in position C-5 in sialic acid affected the rate
of deprotection of C-9 TBDMS. In the presence of the
proton at the nitrogen atom, the cleavage of C-9 TBDMS of
compounds 11a and 11b proceeded more quickly than that
of compounds 9 and 16.
catalytic amount of CBr4 in MeOH formed 1923 in good
yields (81–95%). As shown in Table 3, Ac, Bz, Bn and acid-
sensitive protecting groups, such as PMB, MMB, Ts,
TBDMS, and allyl ethers, were unaffected under the
reaction conditions. The PMB group, which undergoes
cleavage in the presence of CBr4 under methanol reflux
conditions, survived under photoirradiation (Entry 7).
According to Table 4, many acid labile acetonide protecting
groups were selectively hydrolyzed by the CBr4-photo-
irradiation protocol (Entries 1–6).24 Notably, in the
deprotection of isopropylidene of compound 32, the internal
isopropylidene was more easily cleaved than the terminal
isopropylidene. The difference in reactivity may follow
from electron withdrawal properties of the Ms group. As
expected, the benzylidene group was deprotected with this
protocol, yielding 35 (83%) and 37 (86%) from 34 and 36.
2.2. Deprotection of isopropylidene and benzylidene
Following the success of the selective cleavage of TBDMS
ethers, whether the protocol could be effective in selectively
cleaving the isoproylidene group in sugar derivatives was
examined (Table 3). Selectively deprotecting of the five-
membered 5,6-O-isopropylidene group in 18 using a
2.3. Deprotection of trityl protecting group
The cleavage of trityl-protected saccharides 38–5625 and
nucleotides 39–52 by the same method also proceeded
smoothly with high yields (Table 5). Other protecting

M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
11469
Table 5. Deprotection of trityl group from saccharides and nucleotides with 5 mol% CBr4/MeOH
Entry
1
Substratea
Time (h)b
8
Product26
Yield (%)c
38
40
39
41
90
2
3
6
5
86
42
43
93
4
5
44
46
9
8
45
47
88
95
6
48
38
49
91
7
8
50
52
12
9
51
53
91
90
9
54
56
13
12
55
57
97
94
10
a Tr, triphenylmethyl; Tol , p-methylbenzoyl; PMB, p-methoxybenzyl.
b Irradiated for 0.5 h then stirred at room temperature.
c The isolated yield after chromatographic purification.
groups present on the substrates were unaffected and no
protecting group migrated during the reaction.
4. Experimental
4.1. General
3. Conclusion
1
The H NMR (proton nuclear magnetic resonance) spectra
were recorded at 300 MHz (Bruker-AC300P) with deuterio-
chloroform (CDCl3, Aldrich 99.8 atom% D) as the solvent
and the internal standard. The 13C NMR (carbon nuclear
magnetic resonance) spectra were recorded at 75.5 MHz
(Bruker-AC300P) with CDCl3 as the solvent and the
internal standard. Chemical shifts are reported in parts per
million and resonance patterns are reported with the
notations of either s (singlet), d (doublet), t (triplet), q
(quartet), or m (multiplet). Coupling constant (J) are
reported in hertz (Hz). MeOH was distilled from magnesium
and recirculated prior to use. Hexane and ethyl acetate were
distilled from calcium hydride. Thin-layer-chromatography
This work described a novel and efficient method for
chemoselectively removing TBDMS, isopropylidene,
benzylidine, trityl groups using CBr4 in MeOH. The method
provides several advantages, including operational simpli-
city, mild reaction conditions, compatibility with other acid
sensitive functional groups, low cost of the reagents and
high yields of the deprotected products. This method should,
therefore, have broad applications in carbohydrate chem-
istry, in which the selective deprotection of acid labile
ethers is an important requirement. The authors believe that
this elegant method of deprotection method will also have
many applications in natural product synthesis.

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M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
(TLC) analysis was performed on a plastic plate (or glass
plate) precoated with silica gel (Merck, 5554 Silica gel 60
F254). Visualization was accomplished by UV light or
developed by spraying with a 10% phosphomolybdic acid
ethanol solution. Column chromatography was performed
using silica gel (Merck, 230–400 mesh) and ethyl/hexane
mixture as the eluent.
0.05 (s, 3H), 0.06 (s, 3H), 0.07 (s, 3H), 0.10 (s, 3H), 0.12
(s, 3H), 0.13 (s, 3H), 0.90 (s, 9H), 0.91 (s, 9H), 0.94 (s, 9H),
1.94 (br s, OH, 1H), 3.62 (dd, JZ6.3, 2.0 Hz, 1H),
3.86–3.91 (m, 2H), 3.94–3.99 (m, 4H), 4.22 (dd, JZ13.2,
4.9 Hz, 1H), 4.85 (d, JZ4.9 Hz, 1H), 5.15 (dd, JZ10.4,
1.3 Hz, 1H), 5.31 (dd, JZ14.0, 1.3 Hz, 1H), 5.87–6.00
(m, 1H). 13C NMR (75 MHz, CDCl3) d K4.9, K4.6, K4.3,
K4.1, K4.0, K3.7, 18.3, 18.4, 18.6, 26.0, 26.1, 26.4, 62.3,
68.8, 70.6, 72.3, 73.8, 83.2, 90.8, 116.4, 134.4. HRMS (EI)
Calcd for C27H59O6Si3 [MCH]C: 563.3619. Found:
563.3633.
4.2. General deprotection procedure using CBr4/MeOH
photoirradiation conditions
A solution of protected saccharide (1.0 equiv), CBr4
(0.05 equiv) and anhydrous MeOH (10 mL/1.0 equiv
saccharide) in a pyrex round bottom was irradiated by a
TLC-lamp (Uvltec Limited, 245 nm, 8 W) for 0.5 h,
followed by stirring without irradiation at room tempera-
ture. After the reaction was complete (by TLC), the organic
solvent was removed directly under reduced pressure.
Further purification was achieved on a flash chromatograph
with silica gel and ethyl acetate/hexane.
4.2.5. p-Methylphenylsulfinyl 2,3-di-O-benzyl-4-O-tert-
butyldimethylsilyl-b-D-galactopyranoside (2e). H NMR
1
(300 MHz, CDCl3) d 0.05 (s, 3H), 0.07 (s, 3H), 0.90 (s, 9H),
2.19 (br s, 1H, OH), 2.33 (s, 3H), 3.45 (dd, JZ9.4, 2.5 Hz,
1H, H-3), 3.48 (dd, JZ7.8, 4.3 Hz, 1H, H-5), 3.60 (dd, JZ
11.1, 4.3 Hz, 1H, H-6), 3.80 (t, JZ9.4 Hz, 1H, H-2), 3.91
(dd, JZ11.1, 7.8 Hz, 1H, H-6), 4.04 (d, JZ2.5 Hz, 1H, H-
4), 4.55 (d, JZ9.4 Hz, 1H, H-1), 4.71 (s, 2H), 4.72 (d, JZ
10.3 Hz, 1H), 4.76 (d, JZ10.3 Hz, 1H), 7.09 (d, JZ8.0 Hz,
2H), 7.26–7.40 (m, 10H), 7.48(d, JZ8.0 Hz, 2H). 13C NMR
(75 MHz, CDCl3) d K5.0, K3.9, 18.5, 21.1, 26.0, 62.9,
69.2, 73.4, 75.2, 76.6, 80.0, 83.6, 87.3, 127.5, 127.6, 127.8,
128.1, 128.2, 128.3, 129.6, 129.7, 132.3, 137.3, 138.0,
138.3. HRMS (EI) Calcd for C33H45O5SSi [MCH]C:
581.2757. Found: 581.2774.
4.2.1. p-Methylphenylsulfinyl 2,3,4-tri-O-tert-butyldi-
methylsilyl-b-D-galactopyranoside (2a). 1H NMR
(300 MHz, CDCl3) d 0.09 (s, 3H), 0.10 (s, 3H), 0.11
(s, 3H), 0.14 (s, 3H), 0.15 (s, 3H), 0.16 (s, 3H), 0.91 (s, 9H),
0.93 (s, 9H), 0.98 (s, 9H), 2.02 (br s, 1H), 2.32 (s, 3H), 3.78–
3.83 (m, 2H), 3.85–3.88 (m, 1H), 4.02–4.05 (m, 1H), 4.13
(dd, JZ9.0, 2.8 Hz, 1H), 4.54 (d, JZ2.8 Hz, 1H), 5.01
(d, JZ9.0 Hz, 1H), 7.11 (d, JZ7.9 Hz, 2H), 7.39 (d, JZ
7.9 Hz, 2H). 13C NMR (75 MHz, CDCl3) dK4.9 (2C),
K4.6 (2C), K4.4 (2C), 17.9, 18.3, 18.4, 21.0, 25.8, 25.9,
26.0, 61.9, 68.1, 74.4, 74.9, 78.3, 87.2, 129.9, 130.4, 133.6,
136.8. HRMS (EI) Calcd for C31H61O5SSi3 [MCH]C:
629.3548. Found: 629.3567.
4.2.6. p-Methylphenylsulfinyl 2,3-di-O-p-methylbenzyl-
4-O-tert-butyldimethylsilyl-b-D-galactopyranoside (2f).
1H NMR (300 MHz, CDCl3) d K0.20 (s, 3H), K0.07 (s,
3H), 0.83 (s, 9H), 2.32 (s, 3H), 2.33 (s, 3H), 2.34 (s, 3H),
3.62–3.65 (m, 1H), 3.82 (dd, JZ7.8, 4.0 Hz, 1H), 3.92 (dd,
JZ10.7, 7.8 Hz, 1H), 4.33 (d, JZ2.5 Hz, 1H, H-4), 4.83 (d,
JZ10.1 Hz, 1H, H-1), 5.16 (dd, JZ10.0 Hz, 2.5, 1H, H-3),
5.66 (dd, JZ10.1, 10.0 Hz, 1H), 7.09–7.18 (m, 6H), 7.41 (d,
JZ8.0 Hz, 2H), 7.80 (d, JZ8.2 Hz, 2H), 7.87 (d, JZ
8.2 Hz, 2H). 13C NMR (75 MHz, CDCl3) d K4.9, K4.6,
18.0, 21.2, 21.5, 21.6, 25.6, 62.6, 67.3, 68.6, 76.5, 79.9,
85.4, 126.6, 126.8, 127.0, 129.0, 129.1, 129.5, 129.7, 129.9,
134.4, 138.4, 143.7, 144.0, 165.2, 166.4. HRMS (EI) Calcd
for C35H45O7SSi [MCH]C: 637.2655. Found: 637.2676.
4.2.2. p-Methylphenylsulfinyl 2,3-di-O-tert-butyldi-
methylsilyl-b-D-galactopyranoside (2b). 1H NMR
(300 MHz, CDCl3) d0.09 (s, 3H), 0.10 (s, 3H), 0.13 (s,
3H), 0.16 (s, 3H), 0.92 (s, 9H), 0.94 (s, 9H), 0.98 (s, 9H),
1.90 (br s, 2H), 2.31 (s, 3H), 3.46 (dd, JZ8.8, 2.8 Hz, 1H,
H-3), 3.50–3.54 (m, 1H, H-5), 3.57 (dd, JZ11.0, 4.1 Hz,
1H, H-6), 3.77 (dd, JZ9.0, 8.8 Hz, 1H, H-2), 3.88 (dd, JZ
11.0, 7.8 Hz, 1H, H-6), 3.97 (d, JZ2.8 Hz, 1H, H-4), 4.47
(d, JZ9.0 Hz, 1H, H-1), 7.08 (d, JZ7.9 Hz, 2H), 7.38
(d, JZ7.9 Hz, 2H). 13C NMR (75 MHz, CDCl3) d K4.7,
K4.2 (2C), K4.0, 18.3, 18.4, 21.0, 25.9, 26.0, 62.9, 70.4,
71.6, 76.5, 79.7, 88.9, 129.6, 130.5, 131.4, 137.0. HRMS
(EI) Calcd for C25H47O5SSi2 [MCH]C: 515.2683. Found:
515.2696.
4.2.7. O-Methyl 2,3-di-O-benzyl-4-O-tert-butyldimethyl-
silyl-b-D-galactopyranoside (2g). 1H NMR (300 MHz,
CDCl3) d 0.09 (s, 3H), 0.11 (s, 3H), 0.92 (s, 9H), 2.66 (br
d, 1H, OH), 3.40 (s, 3H), 3.72–3.89 (m, 5H), 4.04–4.07 (m,
1H), 4.67–4.86 (m, 5H), 7.28–7.42 (m, 10H). 13C NMR
(75 MHz, CDCl3) d K4.9, K3.9, 18.5, 26.0, 55.2, 62.9,
70.5, 71.7, 73.4, 73.8, 75.6, 78.0, 98.9, 127.5(2C), 127.8,
128.0, 128.2, 128.4, 138.4, 138.5. HRMS (EI) Calcd for
C27H41O6Si [MCH]C: 489.2672. Found: 489.2690.
4.2.3. O-Methyl 2,3,4-tri-O-tert-butyldimethylsilyl-a-D-
galactopyranoside (2c). 1H NMR (300 MHz, CDCl3) d
0.05 (s, 3H), 0.07 (s, 3H), 0.08 (s, 3H), 0.09 (s, 3H), 0.11
(s, 6H), 0.87 (s, 9H), 0.88 (s, 9H), 0.89 (s, 9H), 2.00 (br s,
1H), 3.39 (s, 3H), 3.58–3.62 (m, 2H), 3.76–3.82 (m, 3H),
4.12–4.16 (m, 1H), 4.65 (d, JZ2.9 Hz, 1H, H-1). 13C NMR
(75 MHz, CDCl3) d K4.7, K4.6, K4.5, K3.9, K3.7,
K3.2, 17.9, 18.0, 18.4, 25.9, 26.0, 26.1, 55.0, 62.8, 72.1,
73.0, 73.6, 75.9, 98.0. HRMS (EI) Calcd for C25H57O6Si3
[MCH]C: 537.3463. Found: 537.3478.
4.2.8. O-tert-Butyldiphenylsilyl-2-azido-3-O-benzoyl-4-
O-tert-butyldimethylsilyl-b-D-galactopyranoside (2h).
1H NMR (300 MHz, CDCl3) d K0.18 (s, 3H), K0.08 (s,
3H), 0.91 (s, 9H), 1.14 (s, 9H), 2.20 (br d, 1H, OH), 3.20 (dd,
JZ7.6, 6.1 Hz, 1H, H-5), 3.27 (dd, JZ10.9, 6.1 Hz, 1H, H-
6), 3.50 (dd, JZ10.8, 7.6 Hz, 1H, H-2), 3.99 (dd, JZ10.9,
7.6 Hz, 1H, H-2), 4.06 (d, JZ2.7 Hz, 1H, H-4), 4.68 (d, JZ
7.6 Hz, 1H, H-1), 4.75 (dd, JZ10.8, 2.7 Hz, 1H, H-3), 7.36–
7.50 (m, 8H), 7.57–7.60 (m, 1H), 7.70–7.80 (m, 4H), 8.05–
8.08 (m, 2H). 13C NMR (75 MHz, CDCl3) d K5.8, K5.7,
4.2.4. O-Allyl 2,3,4-tri-O-tert-butyldimethylsilyl-b-D-
galactopyranoside (2d). 1H NMR (300 MHz, CDCl3) d

M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
11471
18.1, 19.2, 22.6, 25.7, 63.2, 63.8, 67.6, 73.0, 74.6, 97.2,
127.4, 128.2, 128.4, 129.4, 129.6, 129.7, 129.9, 132.7,
133.2, 133.3, 135.8, 135.9, 165.7. HRMS (EI) Calcd for
C35H48N3O6Si2 [MCH]C: 662.3082. Found: 662.3100.
13C NMR (75 MHz, CDCl3) d K4.8, K3.9, 17.9, 21.0, 25.8,
62.3, 68.1, 70.6, 75.2, 80.7, 81.5, 86.6, 87.8, 126.7, 127.1,
127.8, 128.1, 128.3, 128.8, 129.2, 129.8, 130.8, 132.3,
137.8, 138.7. HRMS (EI) Calcd for C33H45O5SSi [MC
H]C: 581.2757. Found: 581.2776.
4.2.9. Phenylselenyl 2-azido-3,4-di-O-tert-butyldimethyl-
silyl-a-D-galactopyranoside (2i). 1H NMR (300 MHz,
CDCl3) d 0.08 (s, 3H), 0.17 (s, 3H), 0.19 (s, 3H), 0.22 (s,
3H), 0.90 (s, 9H), 0.98 (s, 9H), 1.56 (br s, 1H), 3.53 (dd, JZ
11.3, 4.2 Hz, 1H, H-6), 3.73 (dd, JZ11.3, 7.9 Hz, 1H, H-6),
3.86 (dd, JZ9.8, 2.1 Hz, 1H, H-3), 3.94 (d, JZ2.1 Hz, 1H,
H-4), 4.12–4.18 (m, 2H), 6.01 (d, JZ4.8 Hz, 1H, H-1),
7.24–7.29 (m, 3H), 7.61–7.64 (m, 2H). 13C NMR (75 MHz,
CDCl3) d K4.9, K4.5, K3.9, K3.6, 18.4, 18.5, 26.0, 26.3,
62.4, 62.7, 71.7, 73.4, 75.2, 84.8, 128.0, 129.1, 131.5, 135.2.
HRMS (EI) Calcd for C24H44N3O4SeSi2 [MCH]C:
574.2036. Found: 574.2051.
4.2.14. p-Methylphenylsulfinyl 2,3-di-O-p-methylbenzyl-
4-O-tert-butyldimethylsilyl-b-D-glucopyranoside (4e). 1H
NMR (300 MHz, CDCl3) d K0.20 (s, 3H), 0.05 (s, 3H),
0.75 (s, 9H), 2.33 (s, 3H), 2.34 (s, 6H), 3.52–3.58 (m, 1H),
3.73–3.79 (m, 1H), 3.93–3.99 (m, 2H), 4.90 (d, JZ9.8, 1H),
5.26 (dd, JZ9.7, 9.7 Hz, 1H), 5.58 (dd, JZ9.8, 9.7 Hz, 1H),
7.09–7.13 (m, 6H), 7.32–7.35 (m, 2H), 7.76–7.81 (m, 4H).
13C NMR (75 MHz, CDCl3) d K4.8, K4.3, 17.8, 21.1, 21.6,
22.6, 25.5, 61.7, 68.8, 70.9, 76.7, 80.9, 86.3, 126.6, 127.0,
128.4, 129.0(2C), 129.7(2C), 129.8, 133.2, 138.4, 143.6,
143.8, 165.3, 165.8. HRMS (EI) Calcd for C35H45O7SSi
[MCH]C: 637.2655. Found: 637.2676.
4.2.10. p-Methylphenylsulfinyl 2,3,4-tri-O-tert-butyldi-
methylsilyl-b-D-glucopyranoside (4a). 1H NMR
(300 MHz, CDCl3) d 0.06 (s, 3H), 0.08 (s, 3H), 0.10 (s,
3H), 0.11 (s, 3H), 0.13 (s, 6H), 0.88 (s, 9H), 0.89 (s, 9H),
0.91 (s, 9H), 2.04 (br s, 1H), 2.32 (s, 3H), 3.68–3.79 (m,
3H), 3.80–3.89 (m, 3H), 4.90 (d, JZ6.7 Hz, 1H), 7.09 (d,
JZ8.1 Hz, 2H), 7.37 (d, JZ8.1 Hz, 2H). 13C NMR
(75 MHz, CDCl3) d K4.9, K4.4, K4.3, K4.2, K4.1, K4.0,
17.9, 18.0, 18.1, 21.0, 25.8, 25.9, 26.0, 64.0, 71.2, 75.4,
77.2, 82.8, 87.5, 129.6, 131.0, 131.7, 136.8. HRMS (EI)
Calcd for C31H61O5SSi3 [MCH]C: 629.3547. Found:
629.3564.
4.2.15. p-Methylphenylsulfinyl 3,4-tri-O-tert-butyldi-
methylsilyl-2-deoxy-2-(2,2,2-trichloro ethoxycarbonyl-
amino)-b-D-glucopyranoside (4f). 1H NMR (300 MHz,
CDCl3) d 0.07 (s, 3H), 0.10 (s, 3H), 0.12 (s, 3H), 0.87 (s,
9H), 0.89 (s, 9H), 1.99 (br s, 1H), 2.34 (s, 3H), 3.35–3.48
(m, 2H), 3.51 (dd, JZ9.2, 9.2 Hz, 1H), 3.63–3.67 (m, 1H),
3.67–3.71 (m, 1H), 4.74–4.78 (m, 3H), 4.85 (dd, JZ9.2,
2.6 Hz, 1H), 5.23 (br d, JZ12.5 Hz, NH, 1H), 7.11 (d, JZ
8.1 Hz, 2H), 7.36 (d, JZ8.1 Hz, 2H). 13C NMR (75 MHz,
CDCl3) d K4.9, K3.9, K2.7, K1.8, 18.2, 21.0, 21.1, 22.6,
25.8, 53.4, 60.4, 62.2, 71.8, 74.8, 76.8, 80.6, 95.3, 129.9,
130.6, 133.0, 137.3, 156.0. HRMS (EI) Calcd for C28H49
Cl3NO6SSi2 [MCH]C: 688.1885. Found: 688.1902.
4.2.11. p-Methylphenylsulfinyl 2,3-di-O-tert-butyldi-
methylsilyl-b-D-glucopyranoside (4b). 1H NMR
(300 MHz, CDCl3) d 0.06 (s, 3H), 0.10 (s, 3H), 0.13 (s,
3H), 0.19 (s, 3H), 0.84 (s, 9H), 0.90 (s, 9H), 1.80 (br s, 2H),
2.28 (s, 3H), 3.38–3.46 (m, 4H), 3.59 (dd, JZ11.8, 6.0 Hz,
1H), 3.87 (dd, JZ11.8, 2.7 Hz, 1H), 4.51 (d, JZ9.0 Hz,
1H), 7.06 (d, JZ7.9 Hz, 2H), 7.31 (d, JZ7.9 Hz, 2H). 13C
NMR (75 MHz, CDCl3) d K4.9, K4.0, K3.8, K3.6, 18.2,
18.4, 21.1, 25.9, 26.1, 62.5, 71.2, 74.5, 79.9, 80.1, 89.1,
129.7, 130.6, 131.7, 137.6. HRMS (EI) Calcd for
C25H47O5SSi2 [MCH]C: 515.2682. Found: 515.2701.
4.2.16. O-Allyl 2,3,4-tri-O-tert-butyldimethylsilyl-b-D-
mannoside (6). 1H NMR (300 MHz, CDCl3) d 0.04
(s, 3H), 0.07 (s, 3H), 0.09 (s, 3H), 0.10 (s, 3H), 0.13
(s, 3H), 0.14 (s, 3H), 0.88 (s, 9H), 0.90 (s, 9H), 0.94 (s, 9H),
1.82 (br s, 1H, OH), 3.61–3.80 (m, 5H), 3.89 (dd, JZ4.2,
1.8 Hz, 1H), 3.99–4.02 (m, 1H), 4.20 (dd, JZ12.8, 5.0 Hz,
1H), 4.66 (d, JZ5.0 Hz, 1H), 5.15 (dd, JZ10.4, 1.5 Hz,
1H), 5.27 (dd, JZ15.3, 1.5 Hz, 1H), 5.90 (m, 1H). 13C NMR
(75 MHz, CDCl3) d K5.3, K4.8, K4.5, K4.2, K3.8,
K3.7, 17.9, 18.1, 18.2, 25.7, 25.8, 26.0, 62.7, 68.6, 72.0,
73.0, 75.3, 83.2, 100.0, 116.4, 134.5. HRMS (EI) Calcd for
C27H59O6Si3 [MCH]C: 563.3619. Found: 563.3632.
4.2.12. O-Methyl 2,3,4-tri-O-tert-butyldimethylsilyl-b-D-
glucopyranoside (4c). H NMR (300 MHz, CDCl3) d 0.06
1
(s, 3H), 0.07 (s, 3H), 0.08 (s, 3H), 0.09 (s, 3H), 0.11 (s, 3H),
0.14 (s, 3H), 0.88 (s, 9H), 0.89 (s, 9H), 0.91 (s, 9H), 3.38 (s,
3H), 3.56–3.64 (m, 2H), 3.77–3.84 (m, 3H), 3.92 (m, 1H),
4.65 (d, JZ3.0 Hz, 1H). 13C NMR (75 MHz, CDCl3) d
K4.7, K4.6, K4.5, K3.9, K3.7, K3.2, 18.0, 18.1, 18.4,
25.9, 26.0, 26.1, 55.0, 62.9, 72.1, 73.0, 73.5, 75.2, 98.0.
HRMS (EI) Calcd for C25H57O6Si3 [MCH]C: 537.3463.
Found: 537.3478.
4.2.17. 3-O-tert-Butyldimethylsilyl-2-deoxy-b-D-thymi-
dine (8a). 1H NMR (300 MHz, CDCl3) d 0.05 (s, 3H),
0.06 (s, 3H), 0.86 (s, 9H), 2.01 (s, 3H), 2.19–2.30 (m, 2H),
3.02 (br s, 1H, OH), 3.72 (dd, JZ12.6, 3.6 Hz, 1H), 3.86–
3.91 (m, 2H), 4.46 (dd, JZ6.5, 2.6 Hz, 1H), 6.15 (dd, JZ
6.7, 6.5 Hz, 1H), 7.42 (d, JZ1.0 Hz, 1H), 9.62 (br s, 1H,
NH). 13C NMR (75 MHz, CDCl3) d K4.9, K4.8, 12.4, 17.9,
25.7, 40.5, 61.8, 71.5, 86.4, 87.6, 110.8, 137.0, 150.5, 164.2.
HRMS (EI) Calcd for C16H29N2O5Si [MCH]C: 357.1845.
Found: 357.1868.
4.2.13. p-Methylphenylsulfinyl 2,3-di-O-benzyl-4-O-tert-
butyldimethylsilyl-b-D-glucopyranoside (4d). 1H NMR
(300 MHz, CDCl3) d 0.01 (s, 3H), 0.10 (s, 3H), 0.89 (s, 9H),
1.96 (br s, 1H), 2.36 (s, 3H), 3.33–3.37 (m, 1H), 3.46–3.56
(m, 2H), 3.62 (dd, JZ6.2, 3.2 Hz, 1H), 3.69 (dd, JZ5.9,
5.9 Hz, 1H), 3.88 (dd, JZ11.6, 2.7 Hz, 1H), 4.66 (d, JZ
10.1 Hz, 1H), 4.69–4.72 (m, 1H), 4.81 (d, JZ11.6, 1H),
4.93 (d, JZ10.1, 1H), 5.00 (d, JZ11.6, 1H), 7.14 (d, JZ
8.2 Hz, 2H), 7.26–7.34 (m, 10H), 7.54 (d, JZ8.9 Hz, 2H).
4.2.18. 2,3-di-O-tert-Butyldimethylsilyl-b-D-uridine (8b).
1H NMR (300 MHz, CDCl3) d 0.04 (s, 3H), 0.06 (s, 3H),
0.08 (s, 3H), 0.09 (s, 3H), 0.87 (s, 9H), 0.90 (s, 9H), 2.93 (br
s, 1H, OH), 3.720 (d, JZ11.0 Hz, 1H, H-50), 3.94 (d, JZ
11.0 Hz, 1H, H-05 ), 4.08 (br s, 1H, H-40), 4.16 (dd, JZ4.1,
4.0 Hz, 1H, H-3 ), 4.50 (dd, JZ4.9, 4.0 Hz, 1H, H-20), 5.50

11472
M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
(d, JZ4.9 Hz, 1H, H-1), 5.72 (d, JZ7.6 Hz, 1H), 7.69 (d,
JZ7.6 Hz, 1H), 9.35 (br s, 1H, NH). 13C NMR (75 MHz,
CDCl3) d K4.8 (2C), K4.7, K4.4, 17.9, 18.0, 25.7, 25.8,
61.4, 71.5, 73.9, 85.8, 93.4, 102.0, 142.9, 150.4, 163.7.
HRMS (EI) Calcd for C21H41N2O6Si2 [MCH]C: 473.2503.
Found: 473.2520.
12.4 Hz, 1H, H-3eq), 3.28–3.35 (m, 1H, H-5), 3.54 (dd,
J9a–8Z7.6 Hz, J9a–9bZ10.4 Hz, 1H, H-9a), 3.80 (s, 3H,
Me), 3.90–3.93 (m, H-7, 2H, H-9b), 4.02 (dddd, JZ1.6, 2.8,
6.0, 12.4 Hz, 1H, All), 4.02–4.06 (m, 2H, H-4, H-8), 4.09
(dd, 1H, J6–7Z2.0 Hz, J6–5Z10.8 Hz, H-6), 4.27 (dddd, 1H,
All, JZ1.6, 2.8, 5.2, 12.4 Hz), 5.14 (dddd, 1H, JZ1.6, 2.8,
4.8, 10.4 Hz, All), 5.25 (dddd, 1H, JZ1.6, 2.8, 4.8, 17.2 Hz,
All), 5.45 (d, 1H, JZ7.6 Hz, NH), 5.86 (dddd, 1H, JZ5.2,
6.0, 10.4, 17.2 Hz, All). 13C NMR (100 MHz, CD3OD): d
K5.4, K5.3, K5.1, K5.0, K4.6, K4.6, K4.6, K3.9, 17.8,
18.2, 23.8, 25.6, 25.6, 25.6, 26.0, 26.0, 26.0, 26.0, 26.0,
26.0, 26.1, 26.1, 26.1, 41.2, 52.3, 55.5, 64.8, 65.0, 67.7,
74.2, 76.1, 76.8, 98.6, 112.3, 134.0, 168.9, 169.6. HRMS
(FAB) calcd for C39H82NO9Si4 [MCH]C: 820.5066 Found:
820.5081.
4.2.19. 2,3-di-O-tert-Butyldimethylsilyl-b-D-adenosine
(8c). 1H NMR (300 MHz, CDCl3) d K0.58 (s, 3H),
K1.13 (s, 3H), 0.11 (s, 3H), 0.12 (s, 3H), 0.75 (s, 9H),
0.94 (s, 9H), 3.71 (dd, JZ12.4, 1.2 Hz, 1H, H-50), 3.95 (dd,
JZ12.4, 1.5 Hz, 1H, H-50), 4.16 (m, 1H, H-40), 4.33 0(d, JZ
4.5 Hz, 1H, H-30), 4.97 (dd, JZ7.5 Hz, 4.5, 1H, H-2 ), 5.80
(d, JZ7.5 Hz, 1H, H-10), 6.48 (br s, 2H, NH2), 7.94 (s, 1H),
8.33 (s, 1H). 13C NMR (75 MHz, CDCl3) d K5.4, K5.1,
K4.7, K4.4, 17.8, 18.5, 25.8, 26.0, 62.3, 72.0, 75.7, 85.4,
88.3, 120.1, 139.6, 150.0, 152.8, 155.5. HRMS (EI) Calcd
for C22H42N5O4Si2 [MCH]C: 496.2775. Found: 496.2768.
4.2.23. Methyl (p-tolyl 5-acetamido-4,7,8,9-tetra-
O-tert-butyldimethylsilyl-3,5-dideoxy-2-thio-D-glycero-
a-galacto-non-2-ulpyranosid)onate (11b). 1H NMR
(400 MHz, CDCl3) d K0.10 (s, 3H), K0.04 (s, 3H), 0.00
(s, 6H), 0.05 (s, 3H), 0.08 (s, 3H), 0.14 (s, 3H), 0.21 (s, 3H),
0.84 (s, 9H), 0.91 (s, 9H), 0.93 (s, 9H), 0.96 (s, 9H), 1.62
(dd, J3ax–4Z11.6 Hz, J3ax–3eqZ12.8 Hz, 1H, H-3ax), 1.88
(s, 3H, Ac), 2.36 (s, 3H, CH3), 2.60 (dd, J3eq–4Z4.8 Hz,
J3eq–3axZ12.8 Hz, 1H, H-3eq), 3.21–3.24 (m, 1H, H-5),
3.57 (dd, J9a–8Z7.2 Hz, J9a–9bZ10.4 Hz, 1H, H-9a), 3.62
(s, 3H, Me), 3.90 (dd, J7–8Z1.6 Hz, J7–6Z3.2 Hz, 1H, H-7),
3.94 (ddd, J8–7Z1.6 Hz, J8–9bZ4.0 Hz, J8–9aZ7.2 Hz, 1H,
H-8), 4.00–4.04 (m, 1H, H-4), 4.01 (dd, J6–7Z3.2 Hz,
J6–5Z10.4 Hz, 1H, 1H, H-6), 4.16 (dd, J9b–8Z4.0 Hz,
J9b–9aZ10.4 Hz, 1H, H-9b), 5.52 (d, JZ7.6 Hz, 1H, NH),
7.11 (d, JZ8.0 Hz, 2H, Ar), 7.42 (d, JZ8.0 Hz, 2H, Ar).
13C NMR (100 MHz, CD3OD) d K5.2, K5.2, K5.0, K4.8,
K4.6, K4.5, K4.5, K4.1, 17.8, 18.2, 18.6, 18.6, 21.3, 23.9,
25.6, 25.6, 25.6, 26.1, 26.1, 26.1, 26.1, 26.1, 26.1, 26.2,
26.2, 26.2, 41.9, 52.3, 55.4, 65.0, 68.4, 76.2, 76.4, 76.6,
126.2, 129.4, 129.4, 136.4, 136.4, 139.6, 169.2, 169.5.
HRMS (FAB) calcd for C43H84NO8SSi4 [MCH]C:
886.4995 Found: 886.5009.
4.2.20. 2,3-di-O-tert-Butyldimethylsilyl-b-D-guanosine
(8d). H NMR (300 MHz, CDCl3) d K0.28 (s, 3H), 0.00
1
(s, 3H), 0.11 (s, 3H), 0.13 (s, 3H), 0.84 (s, 9H), 0.93 (s, 9H),
3.73 (dd, JZ12.6, 1.9 Hz, 1H, H-50), 4.11 (dd, JZ12.6,
1.0 Hz, 1H, H-50), 4.20 (m, 1H, H-40), 4.28 (dd, JZ4.7,
2.8 Hz, 1H, H-30), 4.57 0(dd, JZ5.9, 4.7 Hz, 1H, H-20), 6.00
(d, JZ5.9 Hz, 1H, H-1 ), 6.35 (br s, 2H, NH2), 6.75 (br s,
1H, NH2), 7.97 (s, 1H), 8.33 (s, 1H). 13C NMR (75 MHz,
CDCl3) d K5.5, K5.0, K4.5, K4.3, 17.9, 18.3, 25.6, 26.1,
61.9, 71.9, 74.5, 81.0, 83.2, 120.1, 138.0, 149.0, 151.0,
155.2. HRMS (EI) Calcd for C22H42N5O5Si2 [MCH]C:
512.2724. Found: 512.2738.
4.2.21. Benzyl (p-tolyl 5-azido-4,7,8-tri-O-tert-butyldi-
methylsilyl-3,5-dideoxy-2-thio-D-glycero-a-galacto-non-
2-ulpyranosid)onate (10). H NMR (300 MHz, CDCl3) d
1
0.00 (s, 6H), 0.01 (s, 3H), 0.07 (s, 3H), 0.13 (s, 3H), 0.20
(s, 3H), 0.87 (s, 9H), 0.88 (m, 1H, H-3), 0.88 (s, 9H), 0.98
(s, 9H), 1.73 (dd, JZ11.6, 9.2 Hz, 1H, H-3), 2.34 (s, 3H),
2.69 (dd, JZ7.6, 3.5 Hz, 1H, H-5), 3.09 (dd, JZ9.5, 1.8 Hz,
1H), 3.30 (dd, JZ7.2, 1.8 Hz, 1H), 3.51–3.59 (m, 3H), 3.83
(m, 1H), 4.03 (br s, 1H, OH), 5.03 (d, JZ2.2 Hz, 2H), 7.10
(d, JZ7.8 Hz, 2H), 7.23–7.27 (m, 3H), 7.34–7.38 (m, 4H).
13C NMR (75 MHz, CDCl3) d K5.8, K5.1, K5.0, K4.8,
K4.7, K4.1, K3.4, K3.0, 14.4, 17.8, 18.1, 18.4, 25.6, 25.7,
26.1, 26.3, 31.6, 41.0, 62.8, 65.8, 67.6, 71.7, 77.8, 87.5,
125.8, 128.5, 128.6, 129.6, 134.9, 136.3, 139.6, 168.3.
HRMS (EI) Calcd for C41H70N3O7SSi3 [MCH]C:
832.4242. Found: 832.4267.
4.2.24. Methyl (O-allyl 5-acetamido-4,7,8-tri-O-tert-
butyldimethylsilyl-3,5-dideoxy-D-glycero-a-galacto-non-
2-ulpyranosid)onate (12a). A solution of saccharide
(100 mg, 0.12 mmol), CBr4 (6 mg, 0.018 mmol) and
anhydrous MeOH (1.2 mL) in a pyrex round bottom was
irradiated by a TLC-lamp (Uvltec Limited, 245 nm, 8 W)
for 0.5 h, followed by stirring without irradiation at room
temperature. After the reaction was completed (by TLC
about 2 h), the organic solvent was removed directly under
reduced pressure. Further purification was achieved on a
flash chromatography with silica gel and ethyl acetate/
hexane(1/2) to get product (57.9 mg, 67%). Rf 0.4 (EA/
HexaneZ1/4). 1H NMR (400 MHz, CDCl3) dK0.08
(s, 3H), 0.01 (s, 6H), 0.05 (s, 3H), 0.10 (s, 3H), 0.20 (s,
3H), 0.87 (s, 9H), 0.93 (s, 9H), 0.94 (s, 9H), 1.75 (dd, J3ax–4
11.6 Hz, J3ax–3eqZ12.8 Hz, 1H, H-3ax), 1.93 (s, 3H, Ac),
2.60 (dd, J3eq–4Z4.4 Hz, J3eq–3axZ12.8 Hz, 1H, H-3eq),
4.2.22. Methyl (O-allyl 5-acetamido-4,7,8,9-tetra-O-tert-
butyldimethylsilyl-3,5-dideoxy-D-glycero-a-galacto-non-
2-ulpyranosid)onate (11a). To a solution of sialic acid
(280 mg, 0.77 mmol) in CH2Cl2 (5 mL) and lutidine
(720 mL, 6.16 mmol) was added TBDMSOTf (1 mL,
4.62 mmol), and the mixture was stirred at room tempera-
ture for overnight. The solution was evaporated in vacuo,
and the residue was purified by column chromatography
(EA/HexaneZ1/4) to yield product (505 mg, 80%). Rf 0.5
3.35–3.42 (m, 1H, H-5), 3.60 (dd, J9a–8Z4.8 Hz, J9a–9b
Z
1
(EA/HexaneZ1/4). H NMR (400 MHz, CDCl3) d K0.08
11.2 Hz, 1H, H-9a), 3.83 (s, 3H, Me), 3.84–3.87 (m, 1H,
OH), 3.93 (dd, J9b–8Z5.6 Hz, J9b–9aZ11.2 Hz, 1H, H-9b),
3.97 (m, 3H, H-4, H-8, H-7), 4.01 (dddd, JZ1.2, 2.8, 6.0,
12.8 Hz, 1H, All), 4.14 (dd, J6–7Z0.8 Hz, J6–5Z10.4 Hz,
1H, H-6), 4.28 (dddd, JZ1.2, 3.2, 5.6, 12.8 Hz, 1H, All),
(s, 3H), K0.03 (s, 3H), 0.01 (s, 6H), 0.03 (s, 3H), 0.07 (s,
3H), 0.13 (s, 3H), 0.21 (s, 3H), 0.88 (s, 9H), 0.90 (s, 9H),
0.91 (s, 9H), 0.93 (s, 9H), 1.72 (t, JZ12.4 Hz, 1H, H-3ax),
1.91 (s, 3H, Ac), 2.59 (dd, J3eq–4Z4.8 Hz, J3eq–3ax
Z

M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
11473
5.15 (dddd, JZ1.2, 2.8, 4.8, 10.4 Hz, 1H, All), 5.21 (d, JZ
7.6 Hz, 1H, NH), 5.27 (dddd, JZ1.2, 3.2, 4.8, 17.2 Hz, 1H,
All), 5.82 (dddd, JZ5.6, 6.0, 10.4, 17.2 Hz, 1H, All). 13C
NMR (100 MHz, CD3OD) d K5.2, K5.0, K4.8, K4.5,
K4.5, K3.9, 17.8, 18.3, 18.5, 23.7, 25.6, 25.6, 25.6, 26.0,
26.0, 26.0, 26.0, 26.0, 26.0, 41.1, 52.6, 55.6, 63.3, 65.1,
67.3, 74.2, 74.7, 77.2, 98.8, 117.2, 133.8, 168.9, 169.7.
HRMS (FAB) calcd for C33H68NO9Si3 [MCH]C: 706.4202
Found: 706.4214.
galacto-non-2-ulpyranosid)onate (13b). 1H NMR
(400 MHz, CDCl3) d K0.09 (s, 3H), K0.01 (s, 3H), 0.02
(s, 3H), 0.05 (s, 3H), 0.12 (s, 3H), 0.19 (s, 3H), 0.87 (s, 9H),
0.89 (s, 9H), 0.98 (s, 9H), 1.71 (dd, J3ax–4Z11.6 Hz,
J3ax–3eqZ12.8 Hz, 1H, H-3ax), 1.90 (s, 3H, Ac), 2.04 (s, 3H,
Ac), 2.34 (s, 3H, CH3), 2.75 (dd, J3eq–4Z4.4 Hz, J3eq–3ax
Z
12.8 Hz, 1H, H-3eq), 3.15–3.22 (m, 1H, H-5), 3.59 (s, 3H,
Me), 3.91–3.93 (m, 2H, H-7, H-9a), 4.01–4.07 (m, 2H, H-4,
H-6), 4.24–4.33 (m, 1H, H-8), 4.31 (dd, J9b–8Z7.6 Hz,
J9b–9aZ12.0 Hz, 1H, H-9b), 5.25 (d, JZ7.6 Hz, 1H, NH),
7.09 (d, JZ8.0 Hz, 2H, Ar), 7.39 (d, JZ8.0 Hz, 2H, Ar).
13C NMR (100 MHz, CD3OD) d K5.6, K5.2, K5.0, K4.5,
K3.8, K3.6, 17.8, 18.0, 18.5, 21.1, 21.3, 23.7, 25.6, 25.6,
25.6, 25.8, 25.8, 25.8, 26.0, 26.0, 26.0, 42.0, 52.2, 56.0,
66.6, 67.8, 74.7, 75.0, 76.0, 87.4, 125.7, 129.4, 129.4, 136.7,
136.7, 139.8, 169.1, 169.7, 170.6. HRMS (FAB) calcd for
C39H72NO9S1Si3 [MCH]C: 814.4235 Found: 814.4241.
4.2.25. Methyl (p-tolyl 5-acetamido-4,7,8-tri-O-tert-
butyldimethylsilyl-3,5-dideoxy-2-thio-D-glycero-a-
galacto-non-2-ulpyranosid)onate (12b). 1H NMR
(400 MHz, CDCl3) d K0.06 (s, 3H), 0.01 (s, 3H), 0.03
(s, 3H), 0.07 (s, 3H), 0.10 (s, 3H), 0.20 (s, 3H), 0.86 (s, 9H),
0.91 (s, 9H), 0.98 (s, 9H), 1.70 (dd, J3ax–4Z11.6 Hz,
J3ax–3eqZ12.8 Hz, 1H, H-3ax), 1.90 (s, 3H, Ac), 2.36 (s, 3H,
CH3), 2.72 (dd, J3eq–4Z4.8 Hz, J3eq–3axZ12.8 Hz, 1H,
H-3eq), 3.27–3.34 (m, 1H, H-5), 3.50 (dd, J9a–8Z4.8 Hz,
J9a–9bZ11.6 Hz, 1H, H-9a), 3.64 (s, 3H, Me), 3.71–3.74
(m, 1H, H-8), 3.91 (dd, J9b–8Z6.0 Hz, J9b–9aZ11.6 Hz, 1H,
H-9b), 3.95–4.03 (m, 3H, H-4, H-6, H-7), 5.19 (d, JZ
7.6 Hz, 1H, NH), 7.14 (d, JZ8.0 Hz, 2H, Ar), 7.43 (d, JZ
8.0 Hz, 2H, Ar). 13C NMR (100 MHz, CD3OD) d K5.2,
K5.0, K4.9, K4.6, K4.5, K3.9, 17.8, 18.3, 18.6, 23.7,
25.6, 25.6, 25.6, 26.0, 26.0, 26.0, 26.1, 26.1, 26.1, 41.7,
52.5, 55.7, 63.3, 67.8, 74.5, 76.1, 77.7, 87.4, 125.3, 129.5,
129.5, 136.8, 136.8, 140.2, 169.0, 169.7. HRMS (FAB)
calcd for C37H70NO8S1Si3 [MCH]C: 772.4130 Found:
772.4127.
4.2.28. Methyl (O-allyl 5-acetamido-7,8-di-O-tert-butyl-
dimethylsilyl-3,5-dideoxy-9-sulfate-D-glycero-a-galacto-
non-2-ulpyranosid)onate (14a). To a solution of sialic acid
(50.0 mg, 0.07 mmol) in dry DMF (5 mL) was added
(Et3)3$SO3 (192.5 mg, 1.06 mmol) and the mixture was
stirred overnight at 50 8C under Ar. Then, TLC showed the
disappearance of starting material and the formation of a
new spot. After the addition of MeOH (5 mL), stirring was
continued for 15 min. The mixture was concentrated and a
solution of residue in MeOH (10 mL) was stirred with
Dowex 50 (NaC) for 1 h, the solution was filtrated and
concentrated under reduced pressure. Further purification
was achieved on a flash chromatography with silica gel and
MeOH/CH2Cl2 (1/4) to get product (44.6 mg, 75%). Rf 0.3
(MeOH/CH2Cl2Z1/4). 1H NMR (400 MHz, CDCl3) d 0.00
(s, 3H), 0.05 (s, 3H), 0.12 (s, 3H), 0.19 (s, 3H), 0.97 (s, 9H),
0.98 (s, 9H), 1.69 (t, 1H, JZ12.4 Hz, H-3ax), 1.99 (s, 3H,
Ac), 2.63 (dd, J3eq–4Z4.4 Hz, J3eq–3axZ12.4 Hz, 1H,
H-3eq), 3.51–3.56 (m, 1H, H-4), 3.76–3.81 (m, 2H, H-5,
H-7), 3.83 (s, 3H, Me), 4.01–4.09 (m, 4H, H-6, H-8, H-9a,
All), 4.37 (dddd, JZ1.2, 3.2, 5.2, 13.2 Hz, 1H, All), 4.65 (d,
JZ10.4 Hz, 1H, H-9b), 5.09 (m, 1H, All), 5.26–5.31 (m,
1H, All), 5.85–5.91 (m, 1H, All). 13C NMR (100 MHz,
CD3OD) d K4.7, K4.2, K3.9, K3.2, 19.3, 19.5, 23.4, 26.8,
26.9, 41.7, 53.1, 54.5, 66.7, 70.0, 71.7, 76.3, 77.0, 77.8,
100.3, 116.8, 135.7, 170.6, 173.8. HRMS (FAB) calcd for
C27H54NO12SSi2 [MCH]C: 672.2905 Found: 672.2890.
4.2.26. Methyl (O-allyl 5-acetamido-9-O-acetyl-4,7,8-tri-
O-tert-butyldimethylsilyl-3,5-dideoxy-D-glycero-a-
galacto-non-2-ulpyranosid)onate (13a). To a solution of
sialic acid (50 mg, 0.07 mmol) in pyridine (2 mL) was
added Ac2O (0.5 mL) at 0 8C, and the mixture was stirred at
room temperature for overnight. The solution was evapor-
ated in vacuo, and the residue was purified by column
chromatography (EA/HexaneZ1/4) to yield product
(50 mg, 94%). Rf 0.3 (EA/HexaneZ1/4). 1H NMR
(400 MHz, CDCl3) d K0.10 (s, 3H), 0.00 (s, 3H), 0.02
(s, 3H), 0.07 (s, 3H), 0.14 (s, 3H), 0.20 (s, 3H), 0.87 (s, 9H),
0.91 (s, 9H), 0.94 (s, 9H), 1.70 (dd, J3ax–4Z11.6 Hz,
J3ax–3eqZ12.8 Hz, 1H, H-3ax), 1.92 (s, 3H, Ac), 2.04 (s, 3H,
Ac), 2.63 (dd, J3eq–4Z4.8 Hz, J3eq–3axZ12.8 Hz, 1H, H-
3eq), 3.21–3.28 (m, 1H, H-5), 3.81 (s, 3H, Me), 3.94–3.95
(m, 1H, H-7), 3.97 (dddd, JZ1.2, 2.8, 5.6, 12.4 Hz, 1H,
All), 4.03 (dd, J9a–8Z4.4 Hz, J9a–8Z10.4 Hz, 1H, H-9a),
4.2.29. Methyl (p-tolyl 5-acetamido-4,7,8-tri-O-tert-
butyldimethylsilyl-3,5-dideoxy-9-sulfate-2-thio-D-gly-
4.05–4.14 (m, 2H, H-4, H-8), 4.19 (dd, J6–7Z1.2 Hz, J6–5
Z
1
cero-a-galacto-non-2-ulpyranosid)onate (14b). H NMR
10.4 Hz, 1H, H-6), 4.27 (dddd, JZ1.6, 3.2, 5.2, 12.4 Hz,
1H, All), 4.55 (d, JZ10.4 Hz, 1H, H-9b), 5.14 (dddd, JZ
1.2, 2.8, 4.8, 10.4 Hz, 1H, All), 5.23–5.28 (m, 1H, All), 5.26
(dddd, JZ1.6, 3.2, 4.8, 17.2 Hz, 1H, All), 5.85 (dddd, JZ
5.2, 5.6, 10.4, 17.2 Hz, 1H, All). 13C NMR (100 MHz,
CD3OD) d K5.3, K5.0, K4.9, K4.6, K4.5, K3.8, 17.8,
18.1, 18.4, 21.0, 23.7, 25.6, 25.6, 25.57, 25.8, 25.8, 25.8,
26.0, 26.0, 26.0, 41.6, 52.4, 55.9, 65.2, 66.9, 67.1, 73.8,
74.8, 75.2, 98.6, 117.0, 134.0, 168.8, 169.8, 170.8. HRMS
(FAB) calcd for C35H70NO10Si3 [MCH]C: 748.4307
Found: 748.4297.
(400 MHz, CDCl3) d K0.04 (s, 3H), 0.00 (s, 3H), 0.03
(s, 3H), 0.10 (s, 3H), 0.12 (s, 3H), 0.20 (s, 3H), 0.85 (s, 9H),
0.93 (s, 9H), 1.00 (s, 9H), 1.60 (dd, J3ax–4Z11.2 Hz,
J3ax–3eqZ12.4 Hz, 1H, H-3ax), 1.90 (s, 3H, Ac), 2.35 (s, 3H,
CH3), 2.60 (dd, J3eq–4Z3.2 Hz, J3eq–3axZ12.4 Hz, 1H,
H-3eq), 3.50–3.53 (m, 1H, H-5), 3.53 (s, 3H, Me), 3.60–
3.64 (m, 2H, H-4, H-9a), 3.91–3.96 (m, 2H, H-8, H-6), 4.10
(dd, J9b–8Z9.2 Hz, J9b–9aZ10.0 Hz, 1H, H-9b), 4.54–4.55
(d, 1H, H-7), 7.20 (d, JZ8.0 Hz, 2H, Ar), 7.45 (d, JZ
8.0 Hz, 2H, Ar). 13C NMR (100 MHz, CD3OD): K4.5, K4.3,
K4.2, K4.1, K3.8, K3.2, 18.8, 19.4, 19.6, 21.5, 23.7, 23.6,
26.3, 26.9, 27.1, 43.0, 53.2, 71.4, 77.3, 78.1, 89.2, 127.4,
130.9, 137.8, 141.5, 170.9, 173.0, 173.1. HRMS (FAB)
4.2.27. Methyl (p-tolyl 5-acetamido-9-acetyl-4,7,8-tri-O-
tert-butyldimethylsilyl-3,5-dideoxy-2-thio-D-glycero-a-

11474
M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
calcd for C37H68NO11S2Si3Na2 [MCNa]C: 896.3337
Found: 896.3350.
1H, H-1). 13C NMR (75 MHz, CDCl3) d 26.2, 26.6, 55.2,
64.2, 69.1, 71.9, 79.9, 81.9, 82.1, 105.1, 111.7, 113.4, 119.9,
129.7, 138.8, 160.0. HRMS (EI) Calcd for C17H25O7 [MC
H]C: 341.1600. Found: 341.1612.
4.2.30. Methyl (O-allyl 5-acetamido-4-acetyl-7,8-di-O-
tert-butyldimethylsilyl-3,5-dideoxy-9-sulfate-D-glycero-
a-galacto-non-2-ulpyranosid)onate (15a). 1H NMR
(400 MHz, CDCl3) d K0.03 (s, 3H), 0.01 (s, 3H), 0.10
(s, 3H), 0.18 (s, 3H), 0.93 (s, 9H), 0.95 (s, 9H), 1.77 (t, JZ
12.0 Hz, 1H, H-3ax), 1.88 (s, 3H, Ac), 2.01 (s, 3H, Ac), 2.60
(dd, J3eq–4Z4.4 Hz, J3eq–3axZ12.0 Hz, 1H, H-3eq), 3.86–
4.07 (m, 5H, H-6, H-7, H-8, H-9a, All), 4.36 (dddd, JZ1.6,
2.4, 5.2, 11.2 Hz, 1H, All), 4.62 (d, JZ9.2 Hz, 1H, H-9b),
4.90 (ddd, J4–3eqZ4.4 Hz, J4–5Z7.2 Hz, J4–3axZ12.0 Hz,
1H, H-4), 5.06–5.09 (m, 1H, All), 5.23–5.28 (m, 1H, All),
5.85 (dddd, JZ5.2, 6.0, 10.8, 17.2 Hz, 1H, All). 13C NMR
(100 MHz, CD3OD) d K5.0, K4.2, K3.9, K2.9, 19.3,
19.5, 21.0, 23.1, 26.8, 26.8, 26.8, 26.9, 26.9, 26.9, 38.5,
51.8, 53.3, 66.8, 71.5, 71.5, 76.2, 76.9, 77.6, 100.1, 116.8,
135.8, 170.4, 172.1, 173.5. HRMS (FAB) calcd for
C29H56NO13SSi2 [MCH]C: 714.3011 Found: 714.3031.
4.2.34. 1,2-Isopropylidene-3-O-(p-toluenesuphonyl)-b-D-
galactofuranose (19h). 1H NMR (300 MHz, CDCl3) d 1.25
(s, 3H), 1.46 (s, 3H), 2.45 (s, 3H), 2.57 (br s, 2H), 3.65–3.68
(m, 1H), 3.84–3.88 (m, 1H), 4.11–4.17 (m, 2H), 4.56 (d, JZ
3.7 Hz, 1H, H-2), 5.00 (d, JZ2.6 Hz, 1H, H-3), 5.86 (d, JZ
3.7 Hz, 1H, H-1), 7.37 (d, JZ8.6 Hz, 2H), 7.83 (d, JZ
8.6 Hz, 2H). 13C NMR (75 MHz, CDCl3) d 21.6, 21.7, 26.5,
64.0, 68.0, 79.0, 81.9, 82.8, 104.9, 112.6, 128.1, 130.1,
132.4, 145.7. HRMS (EI) Calcd for C16H23O8S [MCH]C:
375.1113. Found: 375.1120.
1
4.2.35. 1,2-Isopropylidene-b-D-arabinofuranose (23). H
NMR (300 MHz, CDCl3) d 1.29 (s, 3H), 1.46 (s, 3H), 3.64 (br
s, 2H, OH), 3.96 (dd, JZ12.3, 3.7 Hz, 1H, H-5), 4.03 (dd, JZ
12.3, 4.1 Hz, 1H, H-5), 4.13–4.16 (m, 1H, H-4), 4.27 (br d,
JZ2.6 Hz, 1H, H-3), 4.50 (br d, JZ3.6 Hz, 1H, H-2), 5.95 (d,
JZ3.6 Hz, 1H, H-1). 13C NMR (75 MHz, CDCl3) d 26.1,
26.6, 60.7, 76.4, 79.1, 85.5, 104.7, 111.8. HRMS (EI) Calcd
for C8H15O5 [MCH]C: 191.0919. Found: 191.0914.
4.2.31. Methyl [p-tolyl 5-(N-acetyl-N-benzoyl)amido-4,7,
8-tri-O-benzoyl-9-O-tert-butyldimethylsilyl-3,5-dideoxy-
2-thio-D-glycero-a-galacto-non-2-ulpyranosid]-onate
1
(16). H NMR (400 MHz, CD3OD) d 0.72 (s, 9H), 1.93
(t, J3ax–4ZJ3ax–3eqZ12.0 Hz, 1H, H-3ax), 2.39 (s, 3H, Ac),
3.15 (dd, J3eq–4Z4.8 Hz, J3eq–3axZ12.0 Hz, 1H, H-3eq),
3.29 (s, 3H, CH3), 3.87 (dd, J9a–8Z3.2 Hz, J9a–9bZ11.6 Hz,
1H, H-9a), 4.15 (dd, J9b–8Z7.6 Hz, J9b–9aZ11.6 Hz, 1H,
H-9b), 4.87–4.98 (m, 2H, H-5, H-6), 5.50–5.52 (m, 1H,
H-8), 5.82–5.87 (m, 2H, H–4, H-7), 7.14–7.22 (m, 3H, Ar),
7.31–7.76 (m, 15H, Ar), 7.81–7.92 (m, 3H, Ar), 8.13–8.20
(m, 3H, Ar). 13C NMR (100 MHz, CD3OD) d K5.7, 18.1,
21.4, 25.6, 28.0, 39.0, 52.6, 55.8, 60.8, 68.0, 69.4, 72.4,
72.6, 87.4, 125.6, 126.0, 128.2, 128.4, 128.9, 129.1, 129.6,
129.7, 129.8, 123.0, 130.2, 132.8, 133.1, 133.6. HRMS
(FAB) calcd for C53H58NO12SSi [MCH]C: 960.3449
Found: 960.3457.
4.2.36. (2R,3S,4R,5R)-4,5-O-Isopropylidene-1,2,3,4,5-
dodecanepentol (29). H NMR (300 MHz, CDCl3) d 0.87
1
(t, JZ6.8 Hz, 3H), 1.28–1.36 (m, 10H), 1.36 (s, 6H), 1.73–
1.76 (m, 2H), 3.56 (ddd, JZ10.6, 8.1, 2.4 Hz, 1H), 3.62–
3.70 (m, 3H), 3.80–3.87 (m, 2H). 13C NMR (75 MHz,
CDCl3) d 14.0, 22.6, 25.0, 26.8, 26.9, 29.3, 29.6, 31.8, 34.4,
63.9, 73.0, 73.2, 80.2, 82.8, 109.2. HRMS (EI) Calcd for
C15H31O5 [MCH]C: 291.2171. Found: 291.2175.
4.2.37. (2R,3S,4R,5R)-3-Azido-4,5-O-isopropylidene-
1,2,4,5-decanetetrol (31). H NMR (300 MHz, CDCl3) d
1
0.89 (t, JZ6.6 Hz, 3H), 1.33–1.40 (m, 12H), 1.38 (s, 3H),
1.50 (s, 3H), 1.86 (br s, 2H), 3.21–3.24 (m, 1H), 3.68–3.75
(m, 2H), 3.81–3.84 (m, 1H), 3.99–4.07 (m, 2H). 13C NMR
(75 MHz, CDCl3) d 14.0 (2C), 22.5, 26.2, 26.7, 31.0, 31.5,
48.2, 61.6, 63.8, 72.8, 81.8, 104.5. HRMS (EI) Calcd for
C13H26N3O4 [MCH]C: 288.1923. Found: 288.1931.
4.2.32. Methyl [p-tolyl 5-(N-acetyl-N-benzoyl)amido-4,7,
8-tri-O-benzoyl-3,5-dideoxy-2-thio-D-glycero-a-galacto-
non-2-ulpyranosid]onate (17). 1H NMR (400 MHz,
CD3OD) d 2.01 (dd, 1H, J3ax–4Z11.2 Hz, J3ax–3eq
Z
12.4 Hz, H-3ax), 2.41 (s, 3H, Ac), 3.21 (s, 3H, Me), 3.21–
3.30 (m, 1H, H-3eq), 3.74–3.80 (m, 1H, H-9a), 4.10–4.23
(m, 1H, H-9b), 5.04–5.05 (m, 2H, H-5, H-6), 5.43–5.45
(m, 1H, H-8), 5.68–5.72 (2H, H-4, H-7), 7.16–7.21 (m, 4H),
7.36–7.48 (m, 5H), 7.51–7.78 (m, 10H), 7.91 (d, JZ7.6 Hz,
1H, Ar), 8.02–8.04 (m, 2H, Ar), 8.14–8.21 (m, 2H, Ar). 13C
NMR (100 MHz, CD3OD) d 21.4, 27.9, 39.2, 52.7, 55.8,
60.6, 68.2, 68.5, 72.9, 73.0, 87.5, 125.4, 126.0, 128.3, 128.5,
128.7, 128.9, 129.0, 129.3, 129.7, 129.9, 130.1, 132.7,
133.0, 133.3, 133.8, 136.1, 136.7, 140.2, 164.9, 165.5,
167.1, 168.3, 173.3, 174.0. HRMS (FAB) calcd for
C47H44NO12S [MCH]C: 846.2584 Found: 846.2592.
4.2.38. (2R,3S,4R,5R)-1,2-O-Isopropylidene-3-O-meth-
anesulfonyl-1,2,3,4,5-decanepentol (33a). 1H NMR
(300 MHz, CDCl3) d 0.88 (t, JZ6.7 Hz, 3H), 1.28–1.50
(m, 8H), 1.36 (s, 3H), 1.42 (s, 3H), 1.91 (br s, 2H), 3.16
(s, 3H), 3.53–3.62 (m, 2H), 3.98 (dd, JZ8.8, 7.3 Hz, H-1,
1H), 4.13 (dd, JZ8.8, 6.4 Hz, 1H, H-1), 4.32–4.36 (m, 1H),
5.12 (d, JZ4.3 Hz, 1H, H-3). 13C NMR (75 MHz, CDCl3) d
14.0 (2C), 22.6, 25.1, 26.5, 31.8, 32.9, 38.8, 65.7, 70.4, 73.7,
75.9, 79.1, 109.2. HRMS (EI) Calcd for C14H29O7S
[MCH]C: 341.1634. Found: 341.1644.
4.2.39. (2R,3S,4R,5R)-4,5-O-Isopropylidene-3-O-methane-
sulfonyl-1,2,3,4,5-decanepentol (33b). 1H NMR (300 MHz,
CDCl3) d 0.90 (t, JZ6.7 Hz, 3H), 1.27–1.51 (m, 8H), 1.38
(s, 3H), 1.42 (s, 3H), 1.90 (br s, 2H), 3.15 (s, 3H), 3.82–3.88
(m, 2H), 4.18–4.25 (m, 2H), 4.32 (dd, JZ6.0, 4.3 Hz, 1H,
H-4), 4.76 (d, JZ4.3 Hz, 1H, H-3). 13C NMR (75 MHz,
CDCl3) d 14.1 (2C), 23.6, 26.0, 26.5, 32.5, 34.6, 38.7, 63.8,
71.1, 72.8, 74.1, 82.3, 109.2. HRMS (EI) Calcd for
C14H29O7S [MCH]C: 341.1634. Found: 341.1645.
4.2.33. 1,2-Isopropylidene-3-O-(m-methoxyphenyl)-b-D-
galactofuranose (19f). 1H NMR (300 MHz, CDCl3) d 1.30
(s, 3H), 1.47 (s, 3H), 2.72 (br s, 2H, OH), 3.68 (dd, JZ11.5,
5.4 Hz, 1H, H-6), 3.79 (s, 3H), 3.80 (dd, JZ11.5, 3.3 Hz,
1H, H-6), 4.01 (m, 1H), 4.08–4.13 (m, 2H), 4.53 (d, JZ
11.9 Hz, 1H), 4.60 (d, JZ3.7 Hz, 1H, H-2), 4.67 (d, JZ
11.9 Hz, 1H), 4.68 (d, JZ12.0 Hz, 1H), 5.91 (d, JZ3.7 Hz,

M.-Y. Chen et al. / Tetrahedron 60 (2004) 11465–11475
11475
(d) Ramasamy, K.; Averett, D. Synlett 1999, 709–712.
(e) Farras, J.; Serra, C.; Vilarrasa, J. Tetrahedron Lett. 1998,
39, 327–330.
4.2.40. p-Methylphenylsulfinyl 2,3-di-O-p-methylbenzyl-
b-D-glucopyranoside (45). H NMR (300 MHz, CDCl3) d
1
2.04 (br s, 1H, OH), 2.33 (s, 3H), 2.34 (s, 3H), 2.36 (s, 3H),
3.41 (br s, 1H, OH), 3.58 (m, 1H), 3.82–3.90 (m, 2H), 4.00
(dd, JZ11.8, 3.7 Hz, 1H), 4.86–4.90 (m, 1H), 5.33–5.40 (m,
2H), 7.09–7.19 (m, 6H), 7.35 (dd, JZ6.6, 1.7 Hz, 2H), 7.83
(d, JZ8.2 Hz, 2H), 7.85 (d, JZ8.2 Hz, 2H). 13C NMR
(75 MHz, CDCl3) d 21.1, 21.5, 21.6, 62.4, 69.8, 70.0, 78.2,
80.0, 86.2, 126.0, 126.5, 128.1, 129.0, 129.1, 129.7, 129.8,
130.0, 133.4, 138.5, 144.0, 144.3, 165.2, 167.6. HRMS (EI)
Calcd for C29H31O7S [MCH]C: 523.1790. Found:
523.1802.
`
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Acknowledgements
We thank the Academia Sinica and National Science
Council in Taiwan (NSC 91-2113-M-001-013 and
92-2751-B-001-014-Y) for their financial support. M.Y.C.
also thanks National Taipei College of Nursing for their
financial support.
17. Khalafi-Nezad, A.; Alamdari, R. F. Tetrahedron 2001, 57,
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