Ferric sulfate hydrate-catalyzed O-glycosylation using glycals with or without microwave irradiation

Article abstract of DOI:10.1016/j.tet.2007.10.097

We have developed a novel glycal-based O-glycosylation reaction, in which the substrates are not only peracetyl glycals but also perbenzyl glucals to afford the corresponding 2,3-unsaturated-O-glycosides via Ferrier rearrangement. The reaction of the perbenzyl glucal with various alcohols catalyzed by ferric sulfate hydrate (Fe₂(SO₄)₃·xH₂O) was successfully carried out to give 2,3-unsaturated d-O-glucosides with exclusive α-selectivity and no formation of addition products 2-deoxy hexopyranosides was observed. It is the first report on peralkyl glycal efficiently undergoing Ferrier rearrangement instead of addition of alcohols catalyzed by Lewis acids. Fe₂(SO₄)₃·xH₂O is an effective, convenient, and environmentally benign heterogeneous catalyst. It has low catalytic loading and recyclable without significant loss of activity.

Full text of DOI:10.1016/j.tet.2007.10.097

Available online at www.sciencedirect.com
Tetrahedron 64 (2008) 339e344
www.elsevier.com/locate/tet
Ferric sulfate hydrate-catalyzed O-glycosylation using glycals
with or without microwave irradiation
*
Guisheng Zhang , Qingfeng Liu, Lei Shi, Jiuxia Wang
School of Chemical and Environmental Sciences, Henan Normal University, 46 East Construction Road, Xinxiang, Henan 453007, PR China
Received 24 August 2007; received in revised form 24 October 2007; accepted 26 October 2007
Available online 1 November 2007
Abstract
We have developed a novel glycal-based O-glycosylation reaction, in which the substrates are not only peracetyl glycals but also perbenzyl
glucals to afford the corresponding 2,3-unsaturated-O-glycosides via Ferrier rearrangement. The reaction of the perbenzyl glucal with various
alcohols catalyzed by ferric sulfate hydrate (Fe2(SO4)3$xH2O) was successfully carried out to give 2,3-unsaturated D-O-glucosides with exclu-
sive a-selectivity and no formation of addition products 2-deoxy hexopyranosides was observed. It is the first report on peralkyl glycal efficiently
undergoing Ferrier rearrangement instead of addition of alcohols catalyzed by Lewis acids. Fe2(SO4)3$xH2O is an effective, convenient, and
environmentally benign heterogeneous catalyst. It has low catalytic loading and recyclable without significant loss of activity.
Ó 2007 Elsevier Ltd. All rights reserved.
Keywords: O-Glycosylation; Ferrier rearrangement; Ferric sulfate hydrate; Peracetyl or perbenzyl glucal; 2,3-Unsaturated O-glycosides
1. Introduction
attention. Awide range of catalysts have been employed to form
2,3-unsaturated glycosides, such as BF3$OEt2,16 SnCl4,17
FeCl3,18 Sc(OTf)3,19 InCl3,20 Montmorillonite K-10,21 BiCl3,22
Dy(OTf)3,23 CeCl3$7H2O,24 ZnCl2,25 DDQ,26 NIS,27 K5Co-
W12O40,28 I2,29 CAN,30 HClO4eSiO2,31 Bi(NO3)3$5H2O,32
Fe(NO3)3$9H2O,32b andNbCl5.33 These catalysts included Lewis
acid catalysts and redox reagents. The acid catalysts, usually em-
ployed in sub-stoichiometric amount, generally provide good
anomeric selectivity for the product under ambient conditions.
However, they often suffer from the limited use of acid-labile
glycal donors and acceptors. The oxidants are often required in
stoichiometric amount, and long reaction time and/or high tem-
perature are unavoidable. In addition, the reactions under these
conditions usually give low anomeric selectivity for the product.
Moreover, some of the catalysts are moisture sensitive and expen-
sive. As a result, most of those methods do not satisfy the rule of
green chemistry, and entail the problems of tedious work-up
procedures and expensive reagents and equipment. Therefore,
searching for environmentally benign and more economic
synthetic methods with greater efficiency and more convenient
procedures is still in strong demand.
Ferrier rearrangement is an allylic rearrangement of glycal
esters1e3 in the presence of alcohols leading to 2,3-unsaturated
glycosides. Since Ferrier rearrangement was discovered in
1969,4 it has been routinely used in the area of carbohydrate
chemistry. The unsaturated glycosides obtained through Ferrier
rearrangement play an important role in the transformation of
these compounds into other interesting carbohydrates.5e7 2,3-
Unsaturated glycosides8 have a unique place in carbohydrate
chemistry, since they can be further functionalized and serve
as chiral intermediate8a,9 in the synthesis of biologically active
compounds, such as glycopeptide blocks,10 oligosaccharides,11
and modified carbohydrates.12 In addition, 2,3-unsaturated
glycosides have also been employed in the synthesis of some
important antibiotics,13 nucleosides,14 natural product-like
compounds,2b and various natural products.15
The catalysts for the synthesis of 2,3-unsaturated glycosides
via Ferrier rearrangement have continuously received extensive
In general, the substrates of Ferrier rearrangement are per-
acyl glycals or the glycals at least with 3-O-acyl group.
* Corresponding author. Tel./fax: þ86 373 3325250.
E-mail address: zgs6668@yahoo.com (G. Zhang).
0040-4020/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2007.10.097

340
G. Zhang et al. / Tetrahedron 64 (2008) 339e344
Perbenzyl glycals typically undergo addition reaction to form
the corresponding addition products 2-deoxy O-glycosides
instead of 2,3-unsaturated-O-glycosides. Benzyl is a very im-
portant protecting group in carbohydrate chemistry. To obtain
benzyl-protected 2,3-unsaturated-O-glycosides via Ferrier
reaction, 3-O-acyl-4,6-di-O-benzyl glycal was used as the Fer-
rier reaction substrate.34 In this strategy, the hydroxy groups of
the substrate should be protected selectively with benzyl and
acyl groups. To date, convenient and effective approaches to
benzyl-protected 2,3-unsaturated-O-glycosides directly from
perbenzyl glycal have not been reported. CAN (ceric ammo-
nium nitrate) was the only known reagent providing Ferrier
rearrangement compounds as by-products from perbenzyl gly-
cals. When CAN was applied, the reaction of perbenzyl glycal
and alcohols led to the formation of 2-deoxy-glycoside (3)
along with the Ferrier rearrangement product (2) due to the
competition (Scheme 1).30b It was found that in the reaction
of perbenzyl glucal with methanol, allyl alcohol, and cyclohex-
anol in the presence of 2 mol % of CAN, 2-deoxy products
were formed as the major products along with the Ferrier prod-
ucts in the yields of 38%, 23%, and 18%, respectively (Table
1). Therefore, the development of a new glycal-based glycosyl-
ation method, in which the substrates include both peracyl and
perbenzyl glucals, would represent an important advance.
glucal and perbenzyl glucal. The reaction of peracetyl glucal
with alcohols catalyzed by Fe2(SO4)3$xH2O, as we anticipated,
gave the Ferrier rearrangement products 2,3-unsaturated gluco-
sides. However, this reaction was carried out with perbenzyl glu-
cal, which, to our surprise, was also found to undergo Ferrier
reaction instead of addition reaction. Both peracetyl and perben-
zyl glucals reacted with alcohols catalyzed by Fe2(SO4)3$xH2O
to afford 2,3-unsaturated-O-glucosides in high yields with
exclusive a-selectivity, no formation of 2-deoxy hexopyrano-
sides (addition products) was observed. Encouraged by this re-
sult, we have explored Fe2(SO4)3$xH2O as an efficient catalyst
for Ferrier reaction of both peracetyl and perbenzyl glucals to
synthesize the corresponding 2,3-unsaturated glucosides
(Scheme 2).
2. Results and discussion
To obtain some preliminary information on this syntheti-
cally useful reaction, initial experiments were performed
with peracetyl glucal as the donor and ethanol as the acceptor.
We first examined the reaction between glucal and ethanol
in various solvent systems. Tri-O-acetyl-D-glucal (0.1360 g,
0.5 mmol) was treated with ethanol (1.5 mmol) and Fe2-
(SO4)3$xH2O (0.025 g, 0.005 mmol)37 in CH2Cl2, MeCN,
DMF, (CH3)2CO, or THF at 60 ꢀC to give ethyl 2,3-unsatu-
rated glycopyranoside. Anhydrous acetonitrile was shown to
be superior to the other solvents in terms of yields and reaction
time. To study the effect of the catalyst, the reactions were car-
ried out in acetonitrile in the presence of 10, 5, 2, 1, and
0.5 mol % of Fe2(SO4)3$xH2O. The results showed that
1 mol % of Fe2(SO4)3$xH2O was enough for a fairly high
yield. With 0.5 mol % of Fe2(SO4)3$xH2O, a lower yield was
observed under same reaction period. Meanwhile, we also
tested the effect of reaction temperature on the catalyzed reac-
tion. When the reaction was carried out at room temperature,
the reaction was sluggish. When it was carried out at 60 ꢀC,
the maximum yield was obtained in a short reaction period.
This success encouraged us to study the scope of the reaction
under the optimized condition: in the presence of 1 mol % of
catalyst, anhydrous acetonitrile as reaction solvent, and at
60 ꢀC. The results of using Fe2(SO4)3$xH2O as a catalyst in
the glycosylation are summarized in Table 2 (condition I).
Treatment of 3,4,6-tri-O-acetyl-D-glucal with various alco-
hols under the optimized conditions led to the corresponding
2,3-unsaturated alkyl glycosides (condition I, entries 1e9).
The 1H NMR data of the glycosides confirmed the a-configura-
tion of the glycosyl products formed in the above reactions by
comparison with the literature data. According to the published
results, most of the Ferrier reactions of 3,4,6-tri-O-acetyl-D-
O
OR
O
O
OR
BnO
BnO
BnO
BnO
CAN
+
+
ROH
BnO
BnO
2 (by product)
1
OBn
OBn
3
CH2
Scheme 1. Reaction of perbenzyl glucal promoted by CAN.
Bn =
In our efforts to develop highly efficient methods for func-
tional group transformations, we found Fe2(SO4)3$xH2O as an
effective, reusable, operationally simple, and environmentally
benign catalyst for tetrahydropyranylation35 and preparation
of acylals from aldehydes.36 To further explore the potential
of this reagent, we studied its behavior on both peracetyl
Table 1
Comparison of reaction results of Fe2(SO4)3$xH2O with CAN
Glycal
Alcohol
Catalyst
Yields (%)
2 (a/b)
3 (a/b)
Fe2(SO4)3$xH2O 81 (a only)
CAN 38 (5:1)
Fe2(SO4)3$xH2O 86 (a only)
CAN 23 (4.7:1)
Fe2(SO4)3$xH2O 82 (a only)
d
56 (1.7:1)
d
60 (1.1:1)
d
MeOH
O
BnO
BnO
HO
OBn
HO
CAN
18 (a only) 65 (11.5:1)
O
O
O
R1
Fe2(SO4)3⋅xH2O/MeCN
RO
RO
RO
R1-OH
1
+
condition I: 60 °C, 70-91%
condition II: 80 °C, MW, 400 W, 80-94%
RO
OR
R = Ac, Bn
4 R = Ac
2 R = Bn
Scheme 2. Reactions of glucals catalyzed by Fe2(SO4)3$xH2O.

G. Zhang et al. / Tetrahedron 64 (2008) 339e344
341
glucal gave 2,3-unsaturated glycosides as a mixture of a- and
b-anomers except Montmorillonite K-1021b and NbCl5.33
From the aspects of cost, efficiency, and stereoselectivity,
Fe2(SO4)3$xH2O is superior to the other catalysts used in most
of the known methods.
excellent stereoselectivity with even higher yields and signifi-
cant shorter reaction time.
In view of green chemistry, recyclable catalysts are highly
preferred. In our process, Fe2(SO4)3$xH2O was easily recov-
ered from the reaction mixture by filtration and subsequently
used directly for the next reaction cycle. Using condition I
for the glycosylation of alcohol with the recycled catalyst,
this recycle protocol was repeated four times and the percent-
age of the catalyst recovery was always more than 90%, while
the yields were always more than 84% (Table 3).
Mechanistically, it is proposed that Fe2(SO4)3$xH2O as a
weak Lewis acid could prompt the glycal to an allylic oxo-
nium intermediate via cleavage of the C3 substituent, as shown
in Scheme 3. The exclusive formation of the a-anomer may
arise from the thermodynamic anomeric effect.
In general, perbenzyl glycal catalyzed by Lewis acid un-
dergoes addition of alcohols to form the corresponding addition
products 2-deoxy O-glycosides instead of undergoing Ferrier
rearrangement to afford 2,3-unsaturated-O-glycosides. To
extend the scope of our catalyst, we also performed Fe2-
(SO4)3$xH2O-catalyzed reactions of perbenzyl glucal with var-
ious alcohols (condition I, entries 11e14). These reactions, to
our surprise, also underwent Ferrier reaction instead of addition
onto the glucal. 2,3-Unsaturated-O-glucosides were produced
in high yields with exclusive a-selectivity and no formation
of 2-deoxy hexopyranosides (addition products) was observed.
It is noteworthy that Fe2(SO4)3$xH2O was the first reagent to
catalyze peralkyl glycal undergoing Ferrier rearrangement to
produce 2,3-unsaturated glycoside as the exclusive product.
The scope of the new glycosylation was further examined
in the context of disaccharide synthesis (entries 10 and 15).
It has been found that many natural antibiotics possessing sig-
nificant antitumor and antiviral activities contain O-glycosy-
lated nucleoside substructure. 2,3-Unsaturated glycosides
connected to nucleosides resulting from Ferrier rearrange-
ments are the important intermediates for O-glycosylated
nucleoside. We chose 20,30-di-O-acetyl-uridine (1j) as the gly-
cosyl acceptor to react with both peracetyl and perbenzyl glu-
cals. As shown in Table 2, these reactions also gave high
yields and a-selectivity exclusively. It has been reported that
the a-anomer of the 2,3-unsaturated glycosides adopted the
3. Conclusion
In conclusion, we have demonstrated a new glycal-based gly-
cosylation method to produce 2,3-unsaturated-O-glycosides via
Ferrier rearrangement, in which the substrates can be either
peracetyl glucal or perbenzyl glucal. This is the first report on
peralkyl glycals efficiently undergoing Ferrier rearrangement
without formation of addition products 2-deoxy hexopyrano-
sides. Both peracetyl and perbenzyl glucals underwent the Fer-
rier rearrangement in the presence of Fe2(SO4)3$xH2O to afford
the corresponding 2,3-unsaturated-O-glycosides in excellent
yields and exclusive a-selectivity with or without microwave
irradiation. Fe2(SO4)3$xH2O is an efficient, convenient, and
environmentally benign heterogeneous catalyst, used in very
low percentage, and can be recovered and reused without signif-
icant loss of activity. The excellent a-selectivity, inexpensive,
and reusable catalyst, and environmentally benign characters
make this method an attractive way to prepare 2,3-unsatu-
rated-O-glycosides from glycals.
5
0H5 conformation and the b-anomer the H0 conformation.38
1
Two anomers could be identified by the value of J4 ,5 in H
00 00
NMR spectrum. The 1H NMR of the products 4j and 2j
00 00
showed that the J4 ,5 values (4j: 10.0 Hz, 2j: 10.0 Hz) were
in accord with a favorable a-anomer, in which 400-H and 500-
H were at anti-quasi-axial positions (Fig. 1).5b
4. Experimental section
Meanwhile, in our endeavor to develop a more efficient,
rapid, and eco-friendly method for O-glycosylation, the micro-
wave irradiation-assisted Ferrier rearrangement of peracetyl
and perbenzyl glucals was explored (condition II, Scheme
2). It was found that the reaction of 3,4,6-tri-O-acetyl-D-glucal
with alcohols (1.5 equiv) in the presence of Fe2(SO4)3$xH2O
(1 mol %) in acetonitrile under microwave irradiation afforded
the Ferrier rearrangement products in good yields with very
high a-selectivity. Therefore, further investigations were car-
ried out to explore the optimized reaction conditions.
Effects of the reaction temperature and the power of micro-
wave to the yield of Ferrier product were studied by using the
reaction of 3,4,6-tri-O-acetyl-D-glucal with ethanol. At different
temperatures and under different powers of microwave, the best
yield (up to 89%) was obtained with the microwave irradiation
power of 400 W at 80 ꢀC for 6 min. A variety of alcohols then
reacted with glucals in the presence of Fe2(SO4)3$xH2O
(1 mol %) following the same procedure and the results are
summarized in Table 2 (condition II). Compared with the results
obtained using condition I, condition II also demonstrated
4.1. General remarks
Acetonitrile was distilled from P2O5 followed by distillation
from CaH2 prior to use. All reagents were obtained from com-
mercial sources and used without further purification. Prepara-
tion of 20,30-di-O-acetyl-uridine followed the known reaction
in literature. The reactions under microwave irradiation were
performed in a commercial microwave reactor (XH-100B,
100e1000 W, Beijing Xianghu Science and Technology Devel-
opment Co. Ltd, Beijing, PR China). The temperature of the
reaction mixture was measured by an immersed platinum resis-
tance thermometer. The reactions were all carried out under
a positive pressure of nitrogen and were monitored by TLC on
silica gel 60 F254 (0.25 mm, E. Merck). Column chromatogra-
phy was performed on silica gel 60 (230e400 mesh). The ratio
between silica gel and crude product ranged from 100 to 50:1
1
(w/w). H and 13C NMR spectra were recorded on Bruker
AC-400 NMR spectrometer in solutions of CDCl3 or DMSO-d6
using tetramethylsilane as the internal standard, d values are

342
G. Zhang et al. / Tetrahedron 64 (2008) 339e344
Table 2
Fe2(SO4)3$xH2O-catalyzed Ferrier rearrangement of glucals with alcohols in acetonitrile
Entry
Substrate
Alcohol
Product
Condition Ia
Time (h)
Condition IIb
Time (min)
Yieldc (%)
86
Yieldc (%)
89
O
O
O
O
HO
AcO
AcO
1
1
6
6
1a
4a
O
O
HO
AcO
AcO
2
3
4
2
91
84
89
93
87
92
1b
1c
1d
4b
O
AcO
AcO
HO
2
10
12
4c
O
O
HO
AcO
2.5
AcO
4d
O
AcO
HO
HO
5
6
2.5
87
89
7
90
94
AcO
1e
4e
O
O
AcO
AcO
2
10
O
AcO
AcO
1f
4f
OH
O
O
OAc
AcO
AcO
Bn
7
1.5
85
6
88
4g
1g
O
O
HO
HO
AcO
AcO
8
9
1.5
90
89
7
5
92
91
1h
4h
O
O
AcO
AcO
Cl
Cl
2
1i
4i
O
N
O
N
NH
NH
HO
O
O
O
O
AcO
AcO
85d
6
88e
O
O
10
1.5
AcO OAc
1j
AcO OAc
4j
O
BnO
BnO
O
O
BnO
BnO
Me
CH3OH
1k
11
12
1.5
81
86
4
87
90
OBn
2k
O
O
HO
BnO
BnO
2
10
1h
2h

G. Zhang et al. / Tetrahedron 64 (2008) 339e344
343
Table 2 (continued)
Entry
Substrate
Alcohol
Product
Condition Ia
Time (h)
Condition IIb
Time (min)
Yieldc (%)
82
Yieldc (%)
84
O
O
BnO
BnO
HO
13
2
7
6
1f
OH
2f
O
O
BnO
BnO
Bn
14
2
84
86
2g
1g
O
O
N
NH
NH
HO
O
O
15
1.5
70f
7
80g
O
O
N
BnO
BnO
O
O
AcO OAc
1j
AcO OAc
2j
a
All the reactions were proceeded at 60 ꢀC.
b
All the reactions were irradiated at 80 ꢀC, 400 W, 2450 MHz in a commercial microwave reactor (XH-100B, 100e1000 W, Beijing Xianghu Science and
Technology Development Co. Ltd, Beijing, PR China). It takes about 5 min to achieve 80 ꢀC under 400 W.
c
Isolated yields.
The yield was based on the 70% conversion rate of nucleoside.
d
e
The yield was based on the 75% conversion rate of nucleoside.
The yield was based on the 70% conversion rate of nucleoside.
The yield was based on the 74% conversion rate of nucleoside.
f
g
O
N
O
O
O
O
R'O
R'O
R
R-OH
Fe2(SO4)3⋅ХH2O
H
4"
R'O
R'O
R'O
R'O
R' = Ac, Bn
O
H
NH
1"
PO
2"
O
POCH2
O
OR'
R
5"
H
O
Scheme 3. Proposed mechanism of Fe2(SO4)3$xH2O-catalyzed Ferrier reaction.
4j, 2
P = Ac or Bn; R =
j
OAc OAc
Figure 1. Preferred conformations of compounds 4j and 2j.
was stirred at 60 ꢀC for appropriate time (condition I, Table
2). The reaction was monitored by TLC. After the completion,
the reaction mixture was filtered and the filtrate was evapo-
rated to recover the solvent. The residue was purified through
silica-gel column chromatography. The pure product was char-
acterized by GCeMS and H NMR. The spectral data are
comparable with literature data (4ae4i,32b 2k,16a 2h,39 2f,30b
and 2g40).
given in parts per million, and coupling constants (J ) in hertz.
The high-resolution mass spectra were collected at the Zhengz-
hou University Campus Instrumentation Center.
1
4.2. General procedure for the preparation of 2,3-
unsaturated glycosides from glucals in anhydrous
acetonitrile at 60 ꢀC
4.3. General procedure for the preparation of 2,3-
unsaturated glycosides from glucals under microwave
irradiation
To a stirred solution of 3,4,6-tri-O-acetyl-D-glucal (1 mmol)
and alcohol (3 mmol) in anhydrous acetonitrile (5 mL) was
added Fe2(SO4)3$xH2O (0.01 mmol, 1 mol %). The mixture
To a mixture of 3,4,6-tri-O-benzyl-D-glucal (1 mmol) and
alcohol (3 mmol) was added Fe2(SO4)3$xH2O (1 mol %) in an-
hydrousacetonitrile(2 mL)inaflaskequipped withacondenser,
and then irradiated in the XH-100B microwave oven at 80 ꢀC
and 400 W for several minutes (condition II, Table 2). After
the completion of the reaction, monitored by TLC, the reaction
mixture was treated following the procedure described above.
The products were purified through silica-gel column chroma-
tography. The pure product was characterized by GCeMS and
1H NMR.
Table 3
The reusability of Fe2(SO4)3$xH2O as catalyst for Ferrier reaction
Round
Alcohol
Catalyst
recovered (mg)
Reaction
time (min)
Yielda,b
(%)
1
2
3
4
a
CH3CH2OH
CH3CH2OH
CH3CH2OH
CH3CH2OH
328
310
280
260
60
60
70
80
86
85
85
84
The reactions were carried out at 60 ꢀC.
Isolated yield.
b

344
G. Zhang et al. / Tetrahedron 64 (2008) 339e344
4.4. Characterization of glucosides: 400,600-di-O-acetyl-
200,300-dideoxy-a-D-erythro-hex-200-enopyranosyl-(1/5)-
20,30-di-O-acetyl-uridine (4j) and 400,600-di-O-benyl-
200,300-dideoxy-a-D-erythro-hex-200-enopyranosyl-(1/5)-
20,30-di-O-acetyl-uridine (2j)
6. Srivastava, R. M.; Oliveira, F. J. S.; Silva, L. P.; Filho, J. R. F.; Oliveira,
S. P.; Lima, V. L. M. Carbohydr. Res. 2001, 332, 335.
7. Danishefsky, S. J.; Bilodeau, M. T. Angew. Chem., Int. Ed. 1996, 35, 1380.
8. (a) Fraser-Reid, B. Acc. Chem. Res. 1985, 18, 347; (b) Ferrier, R. J. Adv.
Carbohydr. Chem. Biochem. 1969, 199; (c) Ramnauth, J.; Poulin, O.;
Rakhit, S. P.; Maddaford, S. P. Org. Lett. 2001, 3, 2013.
9. Tolstikov, A. G.; Tolstikov, G. A. Russ. Chem. Rev. 1993, 62, 579.
10. (a) Dorgan, B. J.; Jackson, R. F. W. Synlett 1996, 859; (b) Chambers, D. J.;
Evans, G. R.; Fairbanks, A. J. Tetrahedron: Asymmetry 2005, 16, 45.
11. (a) Seeberger, P. H.; Bilodeau, M. T.; Danishefsky, S. J. Aldrichimica Acta
1997, 30, 75; (b) Danishefsky, S. J.; Bilodeau, M. T. Angew. Chem., Int.
Ed. 1996, 120, 13515.
12. Schmidt, R. R.; Angerbauer, R. Angew. Chem., Int. Ed. Engl. 1977, 16, 783.
13. Williams, N. R.; Wander, J. D. The Carbohydrates in Chemistry and
Biochemistry; Academic: New York, NY, 1980; p 761.
1
Compound 4j: H NMR (400 MHz, DMSO-d6) d 11.29 (s,
1H), 7.62 (d, J¼8.0 Hz, 1H), 5.90e5.80 (m, 3H), 5.66e5.62
(m, 1H), 5.25e5.20 (m, 2H), 5.08 (d, J¼10.0 Hz, 1H), 5.04 (s,
1H), 4.22 (d, J¼2.8 Hz, 1H), 4.03e3.98 (m, 2H), 3.89e3.85 (m,
2H), 3.77e3.67 (m, 2H), 1.99 (s, 3H), 1.94 (s, 3H), 1.92 (s, 3H),
1.90 (s, 3H). 13C NMR (100 MHz, DMSO-d6) d 170.3, 170.1,
169.6, 169.5, 163.1, 150.6, 140.4, 129.8, 127.6, 102.8, 93.7, 86.4,
81.0, 72.5, 70.9, 67.2, 67.0, 63.8, 62.6, 20.9, 20.6, 20.5, 20.4,
HRMS: C23H28N2O13þNa (MþNa)þ calcd 563.1489, found
563.1488.
14. (a) Bracherro, M. P.; Cabrera, E. F.; Gomez, G. M.; Peredes, L. M. R.
Carbohydr. Res. 1998, 308, 181; (b) Schmidt, R. R.; Angerbauer, R.
Carbohydr. Res. 1979, 72, 272.
15. (a) Domon, D.; Fujiwara, K.; Ohtaniuchi, Y.; Takezawa, A.; Takeda, S.;
Kawaski, H.; Murai, A.; Kawai, H.; Suzuki, T. Tetrahedron Lett. 2005,
46, 8279; (b) Reddy, B. G.; Vankar, Y. D. Tetrahedron Lett. 2003, 44,
4765; (c) Lewis, A.; Stefanuti, I.; Swain, S. A.; Smith, S. A.; Taylor,
R. J. K. Tetrahedron Lett. 2001, 42, 5549; (d) Patterson, I.; Keown,
L. E. Tetrahedron Lett. 1997, 38, 5727.
1
Compound 2j: H NMR (400 MHz, DMSO-d6) d 11.28 (s,
1H), 7.64 (d, J¼8.0 Hz, 1H), 7.24e7.13 (m, 10H), 6.07 (d,
J¼10.4 Hz, 1H), 5.88e5.86 (m, 1H), 5.75e5.71 (m, 1H), 5.63
(t, J¼4.0 Hz, 1H), 5.26e5.22 (m, 2H), 4.97 (s, 1H), 4.43e
4.33 (m, 4H), 4.21 (d, J¼2.8 Hz, 1H), 3.89 (d, J¼10.0 Hz, 1H),
3.79e3.66 (m, 3H), 3.54e3.46 (m, 2H), 1.93 (s, 3H), 1.90 (s,
3H). 13C NMR (100 MHz, DMSO-d6) d 169.5, 163.1, 150.6,
140.4, 138.5, 138.3, 131.4, 128.4, 128.0, 127.7, 127.6, 126.0,
102.8, 93.8, 86.4, 81.0, 72.4, 70.9, 70.2, 70.0, 69.5, 69.0, 66.9,
20.5, 20.4. HRMS: C33H36N2O11þH (MþH)þ calcd
637.2397, found 637.2395.
16. (a) Descotes, G.; Martin, J. C. Carbohydr. Res. 1977, 56, 168; (b) Klaffke,
W.; Pudlo, P.; Springer, D.; Thieme, J. Liebigs Ann. Chem. 1991, 509.
17. Grynkiewicz, G.; Priebe, W.; Zamojski, A. Carbohydr. Res. 1979, 68, 33.
18. (a) Masson, C.; Soto, J.; Bessodes, M. Synlett 2000, 1281; (b) Tilve, R. D.;
Alexander, M. V.; Khandekar, A. C.; Samant, S. D.; Kanetkar, V. R.
J. Mol. Catal. A: Chem. 2004, 223, 237.
19. Yadav, J. S.; Reddy, B. V. S.; Murthy, C. V. S. R.; Kumar, G. M. Synlett
2000, 1450.
20. Babu, B. S.; Balasubramanian, K. K. Tetrahedron Lett. 2000, 41, 1271.
21. (a) Shanmugasundaram, B.; Bose, A. K.; Balasubramanian, K. K. Tetra-
hedron Lett. 2002, 43, 6795; (b) Ronaldo, N. O.; Filho, J. R. F.; Srivastava,
R. M. Tetrahedron Lett. 2002, 43, 2141.
Acknowledgements
22. Swamy, N. R.; Venkateswarlu, Y. Synthesis 2002, 598.
23. Yadav, J. S.; Reddy, B. V. S.; Reddy, J. S. S. J. Chem. Soc., Perkin Trans. 1
2002, 2390.
This work was supported by the National Natural Science
Foundation of China (20672031) and a fund from the Program
for New Century Excellent Talents in University of Henan
Province (2006-HACET-06) to G.Z.
24. Yadav, J. S.; Reddy, B. V. S.; Reddy, K. B.; Satyanarayana, M. Tetra-
hedron Lett. 2002, 43, 7009.
25. Bettadaiah, B. K.; Srinivas, P. Tetrahedron Lett. 2003, 44, 7257.
26. Toshima, K.; Ishizuka, T.; Matsuo, G.; Nakata, M.; Konoshita, M.
J. Chem. Soc., Chem. Commun. 1993, 704.
27. Lopez, J. C.; Gomez, A. M.; Valverde, S.; Fraser-Reid, B. J. Org. Chem.
1995, 60, 3851.
Supplementary data
28. Rafiee, E.; Tangestaninejad, S.; Habibi, M. H.; Mirkhani, V. Bioorg. Med.
Chem. Lett. 2004, 14, 3611.
Supplementary data associated with this article can be
found in the online version, at doi:10.1016/j.tet.2007.10.097.
29. Koreeda, M.; Houston, T. A.; Shull, B. K.; Klemke, E.; Tuinman, R. J.
Synlett 1995, 90.
30. (a) Yadav, J. S.; Reddy, B. V. S.; Pandey, S. K. New J. Chem. 2001, 25,
538; (b) Pachamuthu, K.; Vankar, Y. D. J. Org. Chem. 2001, 66, 7511.
31. Agarwal, A.; Rani, S.; Vankar, Y. D. J. Org. Chem. 2004, 69, 6137.
32. (a) Banik, B. K.; Adler, D.; Nguyen, P.; Srivastava, N. Heterocycles 2003,
61, 101; (b) Naik, P. U.; Nara, S. J.; Harjani, J. R.; Salunkhe, M. M.
J. Mol. Catal. A: Chem. 2005, 234, 35.
References and notes
1. (a) Schreiber, S. L. Science 2000, 287, 1964; (b) Spring, D. R. Org. Biomol.
Chem. 2003, 1, 3867; (c) Shang, S.; Tan, D. S. Curr. Opin. Chem. Biol.
2005, 9, 1; (d) Arya, P.; Quevillon, S.; Joseph, R.; Wei, C.-Q.; Gan, Z.;
Parisien, M.; Sesmilo, B.; Reddy, P. T.; Chen, Z.-X.; Durieux, P.; Laforce,
D.; Campeau, L. C.; Khadem, S.; Daroszewska, M.; Barnes, M. L. Pure
Appl. Chem. 2005, 77, 163.
33. Hotha, S.; Tripathi, A. Tetrahedron Lett. 2005, 46, 4555.
34. Kim, H.; Men, H.; Lee, C. J. Am. Chem. Soc. 2004, 126, 1336.
35. Li, L.; Zhu, L.; Zhang, X.; Zhang, G.; Qu, G. Can. J. Chem. 2005, 83, 1120.
36. Zhang, X.; Li, L.; Zhang, G. Green Chem. 2003, 5, 646.
37. Fe2(SO4)3$xH2O used in the experiments was purchased from the Beijing
Chemical Factory (A.R. grade). The mole of Fe2(SO4)3$xH2O is calculated
based on the formula: MFe ðSO Þ ,xH O ¼ 0:5ðWFe ðSO Þ ,xH OFeðIIIÞ%O55:8Þ.
2. (a) Kubota, H.; Lim, J.; Depew, K. M.; Schreiber, S. L. Chem. Biol. 2002,
9, 265; (b) Hotha, S.; Tripathi, A. J. Comb. Chem. 2005, 7, 968.
3. Collins, P.; Ferrier, R. Monosaccharides: their Chemistry and their Roles
in Natural Products; Wiley: Chichester, UK, 1995.
2
4
2
2
4
2
3
3
38. Herscovici, J.; Montserret, R.; Antonakis, K. Carbohydr. Res. 1998, 176,
219.
4. Ferrier, R. J.; Prasad, N. J. Chem. Soc. C 1969, 570.
5. (a) Holder, N. Chem. Rev. 1982, 82, 287; (b) Liu, Z. J.; Zhou, M.; Min,
J. M.; Zhang, L. H. Tetrahedron: Asymmetry 1999, 10, 2119; (c) Brito,
T. M.; Silva, L. P.; Siqueira, V. L.; Srivastava, R. M. J. Carbohydr.
Chem. 1999, 18, 609.
39. Lesueur, C.; Nouguier, R.; Bertrand, M. P.; Hoffmann, P.; De Mesmaeker,
A. Tetrahedron 1994, 50, 5369.
40. Kashyap, S.; Hotha, S. Tetrahedron Lett. 2006, 47, 2021.