Selective Oxidation of Glycosyl Sulfides to Sulfoxides Using Magnesium Monoperoxyphthalate and Microwave Irradiation

Article abstract of DOI:10.1021/jo035698o

A protocol that uses moist magnesium monoperoxyphthalate (MMPP) as an oxidant under microwave irradiation rapidly yields a variety of glycosyl sulfoxides from corresponding sulfides in high yields with high selectivity.

Full text of DOI:10.1021/jo035698o

pounds called C-glycosides.11 The rich chemistry of gly-
cosyl sulfoxides motivates the development of selective
and efficient methods for their synthesis.
Selective Oxid a tion of Glycosyl Su lfid es to
Su lfoxid es Usin g Ma gn esiu m
Mon op er oxyp h th a la te a n d Micr ow a ve
Ir r a d ia tion
Although several methods for oxidizing sulfides to
sulfoxides or sulfones have been developed,1 very few
are sufficiently selective to terminate oxidation at the
2
Ming-Yi Chen,*,† Laxmikant Narhari Patkar,‡ and
Chun-Cheng Lin*,‡
13
sulfoxide stage and prevent overoxidation to sulfones.
Even fewer methods of synthesizing glycosyl sulfoxides
Institute of Chemistry, Academia Sinica, 128, Sec. 2,
Yen-Chiu-Yuan Road, Nankang, Taipei 115, Taiwan,
and General Education Center, Taipei Nursing College,
Taipei 112, Taiwan
have been investigated.4
,14
The oxidation of glycosyl
sulfides to sulfoxides has most successfully been achieved
4
using m-CPBA (m-chloroperbenzoic acid). However, this
method suffers from a number of shortcomings, including
the requirement that a low temperature be maintained
to prevent overoxidation to sulfone, the partial solubility
of m-CPBA in the solvent, and the difficulty of separating
the byproduct, m-chlorobenzoic acid, from the sulfoxide.
Accordingly, a new highly selective method with mild
reaction conditions and simple workup is required. A few
years ago, one such selective and mild method, using
hydrogen peroxide (30%) as an oxidant in the presence
of silica gel, was reported.1 Very recently, we reported
another selective and mild method that involved silica
gel-supported oxone or tert-butyl hydroperoxide (TBHP)
as an oxidant at room temperature, to oxidize glycosyl
cclin@chem.sinica.edu.tw
Received November 18, 2003
Ab st r a ct : A protocol that uses moist magnesium mono-
peroxyphthalate (MMPP) as an oxidant under microwave
irradiation rapidly yields a variety of glycosyl sulfoxides from
corresponding sulfides in high yields with high selectivity.
4g
Sulfoxides are an important class of synthetic inter-
mediates used for stereocontrol in the construction of
chemically and biologically important molecules.
1
-3
In
4
15
carbohydrate chemistry, glycosyl sulfoxides constitute
sulfides to sulfoxides. Herein, a protocol, which rapidly
5
as a distinct class of donors for glycosylation because of
generates various glycosyl sulfoxides and improves upon
the selectivity and efficiency of previously reported
methods, is presented. This protocol uses magnesium
monoperoxyphthalate (MMPP) as an oxidant under
microwave irradiation.
6
the mild conditions under which they react, their good
4
,7
to excellent anomeric stereocontrol, and their adapt-
8
abilities in both solution- and solid-phase synthesis.
9
They have been used in preparing oligosaccharides and
glycoconjugates.10 Moreover, the stereochemical outcome
of such glycosylation is independent of the configuration
(
11) Carpintero, M.; Nieto, I.; Fernandez-Mayoralas, A. J . Org.
Chem. 2001, 66, 1768.
12) (a) Procter, D. J . J . Chem. Soc., Perkin Trans. 1 1999, 641 and
4
at sulfur atom, eliminating the need to prepare diaste-
(
reomerically pure gycosyl sulfoxide donor for glycosida-
tion. Apart from glycosyl donors, glycosyl carbanions,
obtained by sulfinyl-lithium exchange, are useful in the
stereospecific construction of an important class of com-
references therein. (b) The Chemistry of Sulphones, Sulphoxides and
Cyclic Sulphides; Patai, S., Rappoport, H., Eds.; Chichester, UK, 1994.
(c) Uemura, S. In Comprehensive Organic Synthesis; Ley, S. V., Ed.;
Pergman; Oxford, 1991; Vol. 7, p 757.
(13) (a) Zen, Z.-M.; Liou, S.-L.; Kumar, A. S.; Hsia, M.-S. Angew.
Chem., Int. Ed. 2003, 42, 577. (b) Shukla, V. G.; Salgaonkar, P. D.;
Akamanchi, K. G. J . Org. Chem. 2003, 68, 5422. (c) Kar, G.; Saikia,
A. K.; Bora, U.; Dehury, S. K.; Chaudhuri, M. K. Tetrahedron Lett.
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58, 35. (b) Bozo, E.; Demeter, A.; Rill, A.; Kuszmann, J . Tetrahedron:
Asymmetry 2001, 12, 3423. (c) Misbahi, K.; Lardic, M.; Ferrieres, V.;
Noiret, N.; Kerbal, A.; Plusquellec, D. Tetrahedron: Asymmetry 2001,
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H.; Williams, S. J . Aust. J . Chem. 2000, 53, 389. (e) Noureddine, K.
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Tsai, C.-Y.; Zhang, Z.; Wong, C.-H. J . Org. Chem. 1999, 64, 5264. (g)
Ravikumar, K. S.; Zhang, Y. M.; Begue, J .-P.; Bonnet-Delpon, D. Eur.
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J . J . Org. Chem. 1996, 61, 8347. (m) Schmidt, R. R.; Kast, J .
Tetrahedron Lett. 1986, 27, 4007.
*
To whom correspondence should be addressed. Fax: +886-2-
2
7835007.
†
Taipei Nursing College.
Academia Sinica.
‡
(1) Durst, T. In Comprehensive Organic Chemistry; Barton, D., Ollis,
W. D., Eds.; Pergamon: Oxford, UK, 1979; Vol. 3, p 121.
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Synthesis 1981, 185.
3) (a) Ikemoto, N.; Schrieber, S. L. J . Am. Chem. Soc. 1990, 112,
(
(
9
1
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14, 4518.
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Soc. 1989, 111, 6881.
(
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(
(
(
1
(
Kahne, D. J . Am. Chem. Soc. 1996, 118, 9239. (c) Zhang, H.; Wang,
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D.; Yang, D.; Kahne, D. J . Am. Chem. Soc. 1994, 116, 1766.
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(
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Res. 2003, 338, 1327.
1
0.1021/jo035698o CCC: $27.50 © 2004 American Chemical Society
Published on Web 03/11/2004
2
884
J . Org. Chem. 2004, 69, 2884-2887

TABLE 1. Oxid a tion of Glycosyl Su lfid e (1) to Su lfoxid e (2)a
c
yield (%)
entry
oxidant
adsorbent
Al2O3
water (µL)
conditionb
time (h)
sulfoxide
sulfide
sulfone
1
2
3
4
5
6
7
8
9
MMPP
MMPP
MMPP
MMPP
MMPP
A
A
A
B
C
A
B
A
B
A
B
10
6
6
0.7
3
6
0.5
6
0.7
7
96
10
8
500
50
50
50
50
86
84
90
85
traced
4
6
11
97
95
12
13
15
16
trace
e
NaIO4
NaIO4
NaIO4
NaIO4
e
50
e
silica gel
silica gel
silica gel
400
400
20
83
80
76
78
8
e
trace
3
trace
f
1
1
0
1
OXONE
OXONEf
20
0.7
a
b
c
Mixture of R and S isomers. Condition A: Stirred at 25 °C. Condition B: Microwave heating. C: conventional heating. Isolated
yield. d The use of exess MMPP (2 mmol) affords the corresponding glycosyl sulfone 3. e 1.7 mmol. f 1.5 mmol of KOSO2OOH.
Magnesium monoperoxyphthalate is a commercially
available and safe alternative to commonly used per-
Initially, glycosyl sulfide 1 was chosen as the model
substrate to study its oxidation to glycosyl sulfoxide 2.
Table 1 summarizes the results. When dry MMPP and
dichloromethane was used, glycosyl sulfide 1 was recov-
ered almost quantitatively (entry 1), even with stirring
for 10 h, since only moist MMPP is known to generate
the desired reaction products.1 MMPP adsorbed over
moist alumina (entry 2) resulted in 86% conversion to
glycosyl sulfoxide 2 with 10% recovery of the starting
sulfide after stirring for 6 h at room temperature.
Without alumina support, but in the presence of a small
amount of water (50 µL), similar results were obtained
(entry 3). Conventional heating in an oil bath at 60 °C
took 3 h (entry 4) to afford 85% conversion and 11%
recovery of the starting sulfide. Dramatic acceleration of
the reaction was observed under microwave conditions;
only 0.7 h of irradiation was required to give 90%
conversion to glycosyl sulfoxide 2, with 6% recovery of
the starting sulfide 1 (entry 5). Notably, the amount of
MMPP per mole of glycosyl sulfide should be only slightly
above 1 equiv: the use of excess (such as 2 equiv) led to
the formation of the corresponding sulfone 3 rather than
the sulfoxide. Other oxidants, including sodium periodate
and oxone, produced slightly lower yields of glycosyl
sulfoxide 2 (entries 8-11) and the recovery of more
starting sulfide 1, both at room temperature and under
microwave irradiation, implying the superiority of MMPP
as an oxidant for oxidizing glycosyl sulfides to glycosyl
sulfoxides. These findings also indicated that the “mi-
crowave effect” reduced the required reaction time (entry
oxy acid oxidants for oxidizing various functional
groups.1
3g,i,14a,l,16
Its stability and the fact that it need not
be assayed before use make it particularly attractive.
However, its solubility in only polar solvents has greatly
limited its acceptability as a popular oxidant. This
limitation has recently been overcome using moist MMPP
on a solid support such as silica gel13i or bentonite and
a relatively nonpolar solvent such as dichloromethane.
Moreover, a recent report described the use of no adsor-
bent in converting sulfides to sulfoxides using MMPP,
with the reactions accelerated by microwave heating.1
Although microwave heating is extensively used to ac-
3f
17
3g
1
8
celerate reactions in other areas of organic synthesis,
its use in carbohydrate chemistry is very limited.19 This
work investigates the micowave protocol for converting
glycosyl sulfides to sulfoxides.
(
16) (a) Heaney, H.; Newbold, A. J . Tetrahedron Lett. 2001, 42, 6607.
(
b) Lee, K.; Im, J .-M. Tetrahedron Lett. 2001, 42, 1539. (c) Fernandez,
R.; Ferrete, A.; Lassaletta, J . M.; Llera, J . M.; Monge, A. Angew. Chem.,
Int. Ed. 2000, 39, 2893. (d) Heaney, H. Aldrichim. Acta 1993, 26, 35.
(e) Brougham, P.; Cooper, M. S.; Cummerson, D. A.; Heaney, H.;
Thompson, N. Synthesis 1987, 1015. (f) Hirano, M.; Ueno, Y.; Morimoto,
T. Synth. Commun. 1995, 25, 3125.
(
17) Hirano, M.; Ueno, Y.; Morimoto, T. Synth. Commun. 1995, 25,
125.
18) Microwaves in Organic Synthesis; Loupy, A., Ed; Wiley-VCH:
Weinheim, 2002.
19) (a) Das, S. K.; Reddy, K. A.; Roy, J . Synlett 2003, 11, 1607. (b)
3
(
(
P e´ rez-Balderas, F.; Ortega-Mu n˜ oz M.; Morales-Sanfrutos, J .; Hern a´ n-
dez-Mateo, F.; Calvo-Flores, F. G.; Calvo-As ´ı n, J . A.; Isac-Garc ´ı a, J .;
Santoyo-Gonz a´ lez, F. Org. Lett. 2003, 5, 1951. (c) Bailliez, V.; de
Figueiredo, R. M.; Olesker, A.; Cleophax, J . Synthesis 2003, 1015. (d)
Das, S. K.; Reddy, K. A.; Abbineni, C.; Roy, J .; Rao, K. V. L. N.;
Sachwani, R. H.; Iqbal, J . Tetrahedron Lett. 2003, 44, 4507. (e)
Maugard, T.; Gaunt, D.; Legoy, M. D.; Besson, T. Biotechnol. Lett. 2003,
8
vs 9 and entry 10 vs 11). It should be noted that no
solid support was required when MMPP or oxone is used
under microwave irradiation conditions (entries 4 and
2
5, 623. (f) Shanmugasundaram, B.; Bose, A. K.; Balasubramanian,
1
1).
K. K. Tetrahedron Lett. 2002, 43, 6795. (g) de Oliveira, R. N.; de Freitas
Filho, J . R.; Srivastava, R. M. Tetrahedron Lett. 2002, 43, 2141. (h)
Soderberg, E.; Westman, J .; Oscarson, S. J . Carbohydr. Chem. 2001,
Next, the generality of this protocol was examined by
subjecting glycosides with various types of protective
groups to the established reaction conditions; Table 2
shows the results. Glycosyl sulfides were observed to
undergo smooth oxidation to the corresponding sulfoxides
within periods from 10 to 45 min, with yields of over 80%.
All the protective groups remained intact during the
reactions and no overoxidation to sulfone wwas observed
on the basis of TLC analysis. The levulinyl group (entry
2
0, 397. (i) Nuchter, M.; Ondruschka, B.; Lautenschlager, W. Synth.
Commun. 2001, 31, 1277. (j) Lakhrissi, Y.; Taillefumier, C.; Lakhrissi,
M.; Chapleur, Y. Tetrahedron: Asymmetry 2000, 11, 417. (k) Zare-
vucka, M.; Vacek, M.; Wimmer, Z.; Brunet, C.; Legoy, M.-D. Biotechnol.
Lett. 1999, 21, 785. (l) Limousin, C.; Olesker, A.; Cleophax, J .; Petit,
A.; Loupy, A.; Lukacs, G. Carbohydr. Res. 1998, 312, 23. (m) Limousin,
C.; Cleophax, J .; Petit, A.; Loupy, A.; Lukacs, G. J . Carbohydr. Chem.
1
997, 16, 327. (n) Gelo-Pujic, M.; Guibe-J ampel, E.; Loupy, A.;
Trincone, A. J . Chem. Soc., Perkin Trans. 1 1997, 7, 1001. (o) Sowmya,
S.; Balasubramanian, K. K. Synth. Commun. 1994, 24, 2097.
J . Org. Chem, Vol. 69, No. 8, 2004 2885

TABLE 2. Oxid a tion of Glycosyl Su lfid es
conditions used herein (entries 4, 5, 11, and 12). Interest-
ingly, among the glycosyl sulfides subjected to the oxida-
tion protocol, more polar substances (with the free
hydroxyl groups; entries 3, 6, 8, and 11) underwent faster
oxidation. The electronic effect of the protecting group
on the C-2 of the glcosyl sulfide was also found to
influence the reaction rate. Electron-donating groups
(e.g., ethers) on C-2 resulted in much higher reaction
rates than electron-withdrawing groups (e.g., ester). The
diastereomeric ratios of sulfoxides were determined using
1
H NMR based on the chemical shifts of the anomeric
protons.20 The chemical shifts of the anomeric protons of
the major isomers were further downfield shifted as
compared to those of minor isomers. Interestingly, the
sulfoxide isomer ratios are not similar to those obtained
previously.15 The differences may have been associated
with “microvawe effect” or the oxidant used.
In conclusion, fast generation of various glycosyl sul-
foxides from the corresponding sulfides was developed
by using moist MMPP as an oxidant and microwave
irradiation. This protocol is highly selective and efficient.
It involves the use of a cheap, stable, and safe reagent
and a simple workup. Moreover, this study demonstrates
that this protocol outperforms the other currently avail-
able methods for the synthesis of glycosyl sulfoxides.
Exp er im en ta l Section :
The isolated compounds 17-22, 24, and 25 have previously
been characterized, and the NMR spectral data are in good
agreement with the literature data.15
Oxid a tion of Glycosyl Su lfid e 1 on Su p p or ted Rea gen t.
A round-bottom flask was charged with 0.5 mmol of MMPP, 1.7
mmol of NaIO
support (2.5 g of Fisher A 540 Alumina or NM-Kieselgel 60
0.04-0.063 mm mesh size) and then moistened with an ap-
4
, or 1.5 mmol of Oxone adsorbed on the solid
(
propriate quantity of water (Table 1). A solution of glycosyl
sulfide (1.0 mmol) in dichloromethane (5.0 mL) was added, and
the suspension was stirred at 25 °C or heated in oil bath at room
temperature for the time specified in Table 1.
Oxid a tion of Glycosyl Su lfid es by Micr ow a ve Ir r a d ia -
tion . Solid MMPP (0.52 mmol), moistened with the appropriate
quantity of water, was charged into a 10 mL round-bottom flask.
A solution of glycosyl sulfide (1.0 mmol) in dichloromethane (5
mL) was added to the flask. This stirred suspension was
irradiated for the time specified in Table 2. After completion of
the reaction (checked by TLC), the reaction mixture was filtered
through Celite pad and the solvent was removed on a rotary
evaporator to give crude product. Purification of crude product
was carried out by flash chromatography with ethyl acetate/
hexane as an eluant.
p-Met h ylp h en ylsu lfon yl 2,3,4,6-t et r a -O-a cet yl-â-D-glu -
1
cop yr a n osid e (3): R
f
0.24 (1:2 EtOAc/hexane); H NMR (CDCl
3
,
3
2
00 MHz) δ 1.93 (s, 3H), 1.94 (s, 3H), 1.95 (s, 3H), 2.14 (s, 3H),
.44 (s, 3H), 3.67-3.73 (m, 1H), 4.10 (d, 2H, J ) 3.6 Hz), 4.47
(
d, 1H, J ) 9.6 Hz), 4.84 (dd, 1H, J ) 9.8, 9.6 Hz), 5.12-5.23
13
(
m, 2H), 7.32 (d, 2H, J ) 8.1 Hz), 7.74 (d, 2H, J ) 8.1 Hz);
, 75 MHz) δ 20.3 (2C), 20.4, 20.5, 21.6, 61.1, 67.0,
7.2, 73.2, 75.9, 88.6, 129.4, 130.4, 131.3, 145.7, 169.1, 169.2,
C
NMR (CDCl
3
6
a
+
Tol ) p-methylbenzoyl, Lev ) levulinyl (CH3COCH2CH2COO).
169.8, 170.0; HRMS (EI) calcd for C21
found 487.1194.
27
H O11S [M + H ] 487.1196,
b
The isolated yield after chromatographic purification. The num-
ber in parentheses indicates the ratio of diastereomers on the basis
of H-1 chemical shifts (downfield/upfield).
p -Met h ylp h en ylsu lfen yl 2,3,4,6-t et r a -O-a cet yl-â-D-glu -
1
cop yr a n osid e (16) (m ixtu r e): R
NMR (CDCl , 300 MHz) δ 1.93 (s, 1.5H), 1.96 (s, 1.5H), 1.98 (s,
.5H), 1.99 (s, 6H), 2.04 (s, 1.5H), 2.42 (s, 3H), 3.60-3.64 (m,
.5H), 3.66-3.72 (m, 0.5H), 4.02-4.16 (m, 2H), 4.27 (d, 0.5H, J
f
0.20 (1:2 EtOAc/hexane); H
3
1
0
4
) which has potential to undergo Baeyer-Villiger oxida-
16e
tion with MMPP (and under m-CPBA oxidation) sur-
vived, suggesting the utility of MMPP and its mild
oxidative property. Acid-labile protecting groups, such as
TBDPS and benzylidene, were stable under the reaction
(20) (a) Crich, D.; Mataka, J .; Zakharov, L. N.; Rheingold, A. L.;
Wink, D. J . J . Am. Chem. Soc. 2002, 124, 6028. (b) Khiar, N.
Tetrahedron Lett. 2000, 41, 9059.
2
886 J . Org. Chem., Vol. 69, No. 8, 2004

1
)
9.2 Hz), 4.41 (d, 0.5H, J ) 9.4 Hz), 4.93 (dd, 0.5H, J ) 9.4, 9.3
Hz), 4.99 (dd, 0.5H, J ) 9.3, 9.2 Hz), 5.18-5.30 (m, 2H), 7.32 (d,
H, J ) 8.1 Hz), 7.51-7.57 (m, 2H); 13C NMR (CDCl
, 75 MHz)
δ 20.1 (3C), 21.4 (2C), 61.6 (61.2), 67.4 (67.6), 67.5, 73.5 (73.8),
6.1, 89.6 (91.9), 125.8(125.7), 129.5 (2C) (129.4) (2C), 142.2
142.3), 169.1, 169.2, 170.0, 170.2; HRMS (EI) calcd for C21
another isomer: R
f 3
0.26 (1:1 EtOAc/hexane); H NMR (CH OH-
d
6
, 300 MHz) δ 2.41 (s, 3H), 3.38 (dd, 1H, J ) 9.3, 5.0 Hz), 3.49
2
3
(dd, 1H, J ) 9.3, 9.3 Hz), 3.67-3.76 (m, 2H), 3.89 (dd, 1H, J )
9.8, 9.3 Hz), 3.98 (dd, 1H, J ) 9.3, 5.2 Hz), 4.16 (d, 1H, J ) 9.8
Hz), 5.53 (s, 1H), 7.29-7.31 (m, 3H), 7.36-7.46 (m, 4H), 7.52-
7
(
[
H
27
O
10
S
7.55 (m, 2H); 13C NMR (CH
3
OH-d
6
, 75 MHz) δ 22.3, 69.6, 71.5,
73.0, 76.9, 82.4, 96.0, 103.8, 127.4, 128.4, 129.8 (2C), 130.8, 131.7,
+
M + H ] 471.1324, found 471.1321.
p -Met h ylp h en ylsu lfen yl 2,3-d i-O-b en zoyl-6-ter t-b u t yl-
diph en ylsilyl-â-D-galactopyr an oside (23): R 0.22 (2:1 EtOAc/
, 300 MHz) δ 1.04 (s, 9H), 2.36 (s, 3H),
.53 (br s, 1H), 3.61-3.64 (m, 1H), 3.94-4.00 (m, 3H), 4.74 (d,
H, J ) 9.7 Hz), 5.45 (dd, 1H, J ) 9.8, 9.7 Hz), 5.66 (dd, 1H, J
9.8, 9.7 Hz), 7.23 (d, 2H, J ) 8.1 Hz), 7.36-7.45 (m, 12H),
.64-7.69 (m, 4H), 7.84 (d, 2H, J ) 8.1 Hz). 7.94-7.97 (m, 4H);
+
139.8, 145.0; HRMS (EI) calcd for C20
found 391.1136.
23 6
H O S [M + H ] 391.1134,
f
1
hexane); H NMR (CDCl
2
1
3
p-Meth ylp h en ylsu lfen yl 2,3-d i-O-ben zyl-â-D-glu cop yr a -
n osid e (27) (m ixtu r e): R 0.25 (2:3 EtOAc/hexane); H NMR
(CDCl , 300 MHz) δ 2.39 (s, 3H), 3.43-3.46 (m, 1H), 3.68-3.71
1
f
3
)
(m, 1H), 3.89-4.30 (m, 2.4H), 4.00 (d, 0.8H, J ) 12.0 Hz), 4.38
(d, 0.8H, J ) 12.0 Hz), 4.63-4.78 (m, 4H), 4.92 (d, 0.2H, J )
11.0 Hz), 4.95 (d, 0.8H, J ) 11.0 Hz), 5.31 (s, 0.8H), 5.42 (s, 0.2H),
7
1
3
3
C NMR (CDCl , 75 MHz ) δ 14.0, 19.1 (3C), 20.9, 62.6, 67.4,
7.19-7.39 (m, 18H), 7.86 (d, 1H, J ) 8.2 Hz); 13C NMR (CDCl ,
6
1
1
7
8.7, 77.7, 80.6, 89.6, 125.4, 127.8, 128.2, 128.4, 129.0, 129.6,
29.8, 129.9, 130.0, 132.7, 133.2, 133.4, 133.6, 135.6, 144.2, 145.5,
65.1, 167.1; HRMS (EI) calcd for C43
3
75 MHz) δ 21.6, 68.8 (67.9), 70.0, 71.4 (71.1), 72.6, 73.4 (74.0),
74.6, 81.7 (80.9), 93.6 (92.8), 101.3 (101.9), 126.2, 126.5, 126.6
(2C), 127.5, 127.7 (2C), 127.8 (2C), 127.9 (2C), 128.0 (2C), 128.3,
128.4, 128.6 (2C), 128.8, 128.9, 129.0, 129.1, 129.3, 135.4 (2C),
137.6 (2C), 137.7 (2C), 137.9 (2C), 142.0, 142.2; HRMS (EI) calcd
+
H
45
O
8
SSi [M + H ]
49.2526, found 749.2529. For another isomer:
R
f
0.20 (2:1
, 300 MHz) δ 1.04 (s, 9H), 2.36
s, 3H), 2.56 (br s, 1H), 3.63 (m, 1H), 3.99-4.18 (m, 3H), 4.83 (d,
1
EtOAc/hexane); H NMR (CDCl
(
1
3
+
H, J ) 9.7 Hz), 5.61 (dd, 1H, J ) 9.8, 9.7 Hz), 5.80 (dd, 1H, J
9.8, 9.7 Hz), 7.23 (d, 2H, J ) 8.1 Hz), 7.34-7.47 (m, 12H),
.63-7.70 (m, 4H), 7.84 (d, 2H, J ) 8.1 Hz), 7.93-7.99 (m, 4H);
for C34H35O S [M + H ] 571.2076, found 571.2078.
6
)
7
Ack n ow led gm en t. This research was supported by
Academia Sinica and National Science Council in Tai-
wan (NSC 92-2113-M-001-027 and -013). M.Y.C. also
thanks Taipei Nursing College for financial support. We
thank M.-D. J an for helping us prepare the starting
materials.
1
3
3
C NMR (CDCl , 75 MHz ) δ 14.1, 19.1 (3C), 21.6, 64.0, 70.3,
7
1
1
3.1, 77.8, 82.0, 92.0, 125.4, 127.8, 128.2, 128.4, 129.0, 129.6,
29.8, 129.9, 130.0, 132.7, 133.2, 133.4, 133.6, 135.6, 144.2, 145.5,
65.1, 167.0; MS (EI) 749 (42, [M + H] ), 734 (100).
+
p-Meth ylph en ylsu lfen yl-â-D-glu copyr an oside (26): R
f
0.30
1
(1:1 EtOAc/hexane); H NMR (CH
3
OH-d
6
, 300 MHz) δ 2.49 (s,
3
H), 3.26 (dd, 1H, J ) 9.7, 9.3 Hz), 3.38 (dd, 1H, J ) 9.3, 9.0
Hz), 3.56-3.64 (m, 1H), 3.68-3.78 (m, 2H), 4.35 (dd, 1H, J )
.0, 4.6 Hz), 4.66 (d, 1H, J ) 9.7 Hz), 5.54 (s, 1H), 7.36-7.38
Su p p or tin g In for m a tion Ava ila ble: General experimen-
tal considerations and H and C spectra of compounds 3, 16,
3, 26, and 27. This material is available free of charge via
9
1
13
1
3
(
m, 3H), 7.44-7.51 (m, 4H), 7.66-7.68 (m, 2H); C NMR (CH
OH-d , 75 MHz) δ 22.3, 70.0, 72.8, 73.2, 76.8, 82.3, 96.3, 103.8,
28.4, 128.5, 129.9 (2C), 130.8, 131.6, 139.6, 145.0; HRMS (EI)
3
-
2
6
the Internet at http://pubs.acs.org.
1
+
calcd for C20
23 6
H O S [M + H ] 391.1137, found 391.1134. For
J O035698O
J . Org. Chem, Vol. 69, No. 8, 2004 2887