From methyl D-glucopyranoside to methyl D-allopyranoside via the Mitsunobu reaction

Article abstract of DOI:10.1016/S0008-6215(99)00160-3

Methyl β-D-glucopyranoside reacted with a 4-molar excess of the Mitsunobu reagents (triphenylphosphine-diethyl azodicarboxylate-benzoic acid) under Weinges et al. [Carbohydr. Res., 164 (1987) 453-458] conditions to furnish four differently benzoylated methyl β-D-allopyranosides in a very good overall yield. The same reaction applied to methyl α-D-glucopyranoside yielded allosides in a low yield and nine other sugar products. These results give an insight into the course of the Mitsunobu esterification-inversion reaction. Copyright (C) 1999 Elsevier Science Ltd.

Full text of DOI:10.1016/S0008-6215(99)00160-3

www.elsevier.nl/locate/carres
Carbohydrate Research 320 (1999) 244–249
Note
From methyl
D-glucopyranoside to methyl
D-allopyranoside via the Mitsunobu reaction
Mikhail Kim, Barbara Grzeszczyk, Aleksander Zamojski *
Institute of Organic Chemistry, Polish Academy of Sciences, Ul. Kasprzaka 44, PL-01-224 Warsaw, Poland
Received 14 April 1999; accepted 14 June 1999
Abstract
Methyl b-
azodicarboxylate–benzoic acid) under Weinges et al. [Carbohydr. Res., 164 (1987) 453–458] conditions to furnish
four differently benzoylated methyl b- -allopyranosides in a very good overall yield. The same reaction applied to
methyl a- -glucopyranoside yielded allosides in a low yield and nine other sugar products. These results give an
D-glucopyranoside reacted with a 4-molar excess of the Mitsunobu reagents (triphenylphosphine–diethyl
D
D
insight into the course of the Mitsunobu esterification–inversion reaction. © 1999 Elsevier Science Ltd. All rights
reserved.
Keywords: Methyl a- and b-
D
-glucopyranosides; Benzoylated methyl a- and b-D-allopyranosides; Mitsunobu reaction
(DEAD) and benzoic acid, 1.2 mol equiv for
each OH group, THF, reflux, 1 h) afforded a
product which, after Zemple´n deacylation,
A preparative route to derivatives of
lose consists of inversion of the hydroxyl
group at C-3 in 1,2:5,6-di-O-isopropylidene-a-
-glucofuranose (1) via oxidation to 3-ulose
D
-al-
gave 70% of methyl b- -allopyranoside (5).
D
D
The transient product was not characterized
and its homogeneity was left unknown.
and subsequent reduction of the keto group to
1,2:5,6-di-O-isopropylidene-a- -allofuranose
(2) [1]. Methyl -allopyranosides can be ob-
tained via inversion of configuration at C-3 in
D
We repeated Weinges’ procedure and de-
cided to analyze in detail the product ob-
tained. In fact, it turned out that it was a
mixture of compounds (93%) separable into
five components identified as: methyl 3,6-di-
O-benzoyl- (6, 16.2%), 4,6-di-O-benzoyl- (7,
21.3%), 3,4,6-tri-O-benzoyl- (8, 50.1%), 2,3,
D
the properly substituted methyl
nosides [2].
D-glucopyra-
Looking for a shorter and more efficient
route to methyl -allopyranoside, we focused
D
our attention on a procedure described by
Weinges et al. [3]. Following these authors,
4,6-tetra-O-benzoyl- (9, 4.1%) -b-
osides and methyl 3,6-anhydro-4-O-benzoyl-
-galactopyranoside (10, 1.6%). Products
D
-allopyran-
treatment of methyl b- -glucopyranoside (3)
D
b-D
with an excess of the Mitsunobu reagents
(triphenylphosphine, diethyl azodicarboxylate
6–8 could be readily interrelated by benzoyla-
tion to the same tetrabenzoate 9. Their
configuration and the localization of the ester
* Corresponding author. Tel.: +48-22-632-7030; fax:
+48-22-632-6681.
1
grouping was deduced from H NMR spectra.
E-mail address: awzam@ichf.edu.pl (A. Zamojski)
The structure of 10 was also assigned
0008-6215/99/$ - see front matter © 1999 Elsevier Science Ltd. All rights reserved.
PII: S0008-6215(99)00160-3

M. Kim et al. / Carbohydrate Research 320 (1999) 244–249
245
by its NMR data. Compounds 6–10 have not
been described in the literature up to now.
portion of products, were sugar epoxides i.e.,
-allopyranosides
esterified at C-6 (17, 10.1%) and at C-4 and -6
(18, 14.8%), methyl 2,3-anhydro-4,6-di-O-ben-
two methyl 2,3-anhydro-a-
D
zoyl-a-
D
-gulopyranoside (19, 17.0%), and two
-galactopyranosides
methyl
3,4-anhydro-a-
D
benzoylated at C-6 (20, 9.0%) and at C-2 and
-6 (21, 4.8%).
1. Discussion
The results of the Mitsunobu reaction with
methyl b- -glucopyranoside can be rational-
D
ized by assuming initial formation of oxyphos-
phonium cations at the primary (C-6) and
secondary (C-3) alcohol positions in 3 fol-
lowed by the attack of benzoic acid molecules,
leading to 6. Formation of 7 can be explained
if we assume a migration of the benzoate
grouping from O-3 to O-4. The most abun-
dant tribenzoate 8 was probably formed from
6 by an esterification of O-4 without inversion
of configuration. Esterification with retention
of configuration was observed earlier [4]. The
tetrabenzoate 9 was obtained probably by a
similar process. Of particular interest is the
formation of the anhydro compound 10. Here
an intramolecular attack of 3-OH on the C-6
phosphonium cation leads to a 3,6-anhydro
bridge, and then a C-4 phosphonium salt is
formed undergoing inversion of configuration
by attack of a benzoic acid molecule leading
to 10.
When, in this reaction, DEAD was replaced
by diisopropyl azodicarboxylate (DIAD), four
products were formed: dibenzoates 6 (3%) and
7 (30.5%), tribenzoate 8 (34.6%) and the anhy-
dro compound 10 (6.2%).
Successful conversion of methyl b-
coside to methyl b- -alloside was required in
order to perform the same reactions with the
cheap methyl a- -glucopyranoside (4). The
D-glu-
D
D
reaction of 4 with Mitsunobu reagents under
Weinges’ conditions led to a complex mixture
of products. This mixture was separated by a
combination of column chromatography and
high-performance liquid chromatography
(HPLC), resulting in 11 products, which were
identified on the basis of analytical and spec-
tral data. Two of them, formed in 4.6 and
The Mitsunobu benzoylation reaction of
methyl a- -glucopyranoside (4) was studied in
D
1979 by Grynkiewicz [5]. He found that, with
1.5 mmol of the reagents (PPh3, benzoic acid,
DEAD) in refluxing 9:1 dioxane–pyridine,
only a single product was formed methyl 6-O-
benzoyl-a- -glucopyranoside (cf. also [6]).
D
3.1% yields were, in fact, methyl a- -allopyra-
D
However, we found that with an excess of the
reagents, under relatively harsh Weinges con-
ditions, a variety of products was formed.
Their identification allowed us to deduce the
course of all consecutive reactions. Thus, all
products 11–21 have the benzoate residue at
C-6, which indicates again a facile formation
of the oxyphosphonium cation at the primary
position [5] followed by the reaction with ben-
zoic acid. From the remaining three secondary
nosides, having benzoate groupings located at
C-3 and -6 (11) and C-3, -4 and -6 (12).
Furthermore, two methyl a- -galactopyra-
D
nosides have been isolated, esterified at C-4
and -6 (13, 1.2%) and C-3, -4 and -6 (14,
3.0%), and two methyl a- -glucopyranosides
D
benzoylated in positions C-3 and -6 (15,
10.6%) and C-3, -4 and -6 (16, 3.5%). The
remaining compounds, constituting the major

246
M. Kim et al. / Carbohydrate Research 320 (1999) 244–249
alcohol positions, the Mitsunobu betaine
prefers position 3 (as in the case of 3) to form
the next oxyphosphonium cation. In methyl
with a Jasco DIP 360 automatic polarimeter.
Melting points were determined on a Kofler
apparatus and are uncorrected. NMR spectra
were recorded with a Varian Gemini AC-200
(200 MHz). Mass spectra (LSI MS, positive-
ion mode) were recorded with an AMD-604
mass spectrometer. Thin-layer chromatogra-
phy (TLC) was performed on Kieselgel 60 F254
ready plates and column chromatography on
Silica Gel 230-400 or 70-230 mesh (E. Merck).
High-performance liquid chromatography
(HPLC) was carried out on a Shimadzu ap-
paratus C-R4A, pump unit LC-8A, UV spec-
trometric detector SPD250-6A on a column
SP250/21 Nucleosil 100-7 (Macherey–Nagel).
All reagents used were of commercial origin.
b- -glucopyranoside (3), there is no steric hin-
D
drance from the axial methoxy group, there-
fore the attack of benzoic acid does not meet
any serious opposition and the inversion of
configuration at C-3 is facile. In the a anomer
4, direct reaction with benzoic acid can occur
only with difficulty (Richardson’s ‘‘b-trans-ax-
ial effect’’ [7]) and therefore formation of al-
loside is very limited. A preferred reaction
pathway for the C-3 oxyphosphonium salt is
the intramolecular attack of the the C-2 hy-
droxyl group leading to the 2,3-anhydro com-
pounds, 17 and its 4-O-benzoylated derivative
18. The most abundant (17%) gulo epoxide 19
was probably formed from 17 by inversion of
the configuration at C-4. All 2,3-anhydro
compounds 17–19 were formed in almost 42%
overall yield.
To a suspension of methyl
D
-glucopyra-
noside (b: 3, a: 4) in dry THF (10 mL/mmol)
were added 4.8 mol equiv (1.2 mol equiv for
every hydroxyl group) each of triphenylphos-
phine and benzoic acid. The mixture was
refluxed, and a solution of 4.8 mol equiv of
dialkyl azodicarboxylate in dry THF was
added dropwise. Time of additional heating to
complete the reaction [until no trace of the
substrate was detected by TLC (35:15:3
CHCl3–MeOH–2 M AcOH)] is given below
for each case. The solution was concentrated
to dryness under reduced pressure and, unless
otherwise stated, the residue was taken up in
benzene (3 mL/mmol). Dialkyl hydrazinodi-
carboxylate crystallized on cooling. The pre-
cipitate was filtered off and the filtrate was
concentrated. The residue was treated with
ether (5 mL/mmol) and the precipitate was
filtered off. The filtrate was washed twice with
satd aq NaHCO3 and twice with water, the
organic layer was dried (MgSO4) and concen-
trated to dryness under reduced pressure. The
residue was separated by column chromatog-
raphy, preparative TLC, and by HPLC.
Formation of the galacto compounds can
be interpreted by reactions involving an inter-
mediate C-4 oxyphosphonium cation. Direct
inversion at C-4 of 4 with benzoic acid leads
to galactosides 13 and 14. The C-4 oxyphos-
phonium cation must also be responsible for
the formation of both galacto epoxides 20 and
21 via an intramolecular attack of the C-3
hydroxyl group followed by esterification of
the C-2 hydroxyl group in the case of 21. It is
remarkable that none of the products can be
derived from a C-2 oxyphosphonium cation.
Benzoates of the unchanged substrate, 15 and
16, were most probably formed by a direct
esterification process [4].
From the results described following
Weinges methodology applied to methyl b- -
D
glucopyranoside (3), a practical preparative
route to methyl b- -allopyranoside (5)
D
emerges including detailed knowledge of the
products formed in the reaction. The wealth
Reaction with methyl i- -glucopyranoside
D
of products obtained with methyl a- -glu-
D
(3) and diethyl azodicarboxylate.—A suspen-
sion of 3 (semihydrate, 1 g, 4.9 mmol) in THF
(50 mL) containing triphenylphosphine (PPh3,
6.20 g) and benzoic acid (2.88 g) was treated
with a solution of DEAD (4.11 g) in THF (10
mL) as described above. Time of additional
heating was 1 h. The mixture of products was
separated by column chromatography with
hexane–EtOAc (10:1“1:2) to give (in order
copyranoside (4) is certainly of interest with
regard to the mechanism of the Mitsunobu
reaction in a polyol system.
2. Experimental
General methods.—Optical rotations were
measured for solutions in CHCl3 at 2092 °C

M. Kim et al. / Carbohydrate Research 320 (1999) 244–249
247
of elution): 9 (0.123 g, 4.1%), 10 (0.022 g,
1.6%), 8 (1.248 g, 50.1%), 6 (0.315 g, 15.9%),
and 7 (0.421 g, 21.3%).
133.47, 133.21, 130.09, 129.88, 129.77, 129.68,
129.44, 128.58, 128.49, 128.37 (Ar), 101.86
(C-1), 73.09, 73.09, 70.17, 67.24 (C-2, 3, 4, 5),
64.07 (C-6), 57.09 (OMe). HRMS (LSI MS):
Calcd for C21H22O8+Na+ [M+Na]+,
425.12125. Found: 425.12132.
Reaction with diisopropyl azodicarboxy-
late.—A suspension of 3 (5 g, 24.6 mmol) in
THF (250 mL) was treated as described in
General methods [PPh3 (30.95 g), DIAD
[23.86 g in THF (50 mL), benzoic acid (14.41
g)]. After 2 h of reflux the solution was con-
centrated to dryness under reduced pressure
and the residue was taken up in toluene. The
mixture of triphenylphosphine oxide and di-
isopropyl hydrazinodicarboxylate crystallized
on cooling. The work-up of the reaction mix-
ture followed the general method. Then chro-
matographic column was washed first with 1:2
hexane–ether and then with 2:1 toluene–ether
to furnish 6 (0.294 g, 3.0%), 7 (3.020 g,
30.5%), 8 (4.308 g, 34.6%) and 10 (0.430 g,
6.2%).
Methyl 4,6-di-O-benzoyl-i- -allopyranoside
D
1
(7).—Syrup, [h]D +33° (c 1.35); H NMR
(CDCl3): l 8.08–7.96, 7.61–7.33 (m, 10 H, 2
Ph), 5.17 (dd, 1 H, J4,3 2.8, J4,5 9.8 Hz, H-4),
4.67 (d, 1 H, J1,2 7.8 Hz, H-1), 4.69–4.58 (m,
1 H, H-5), 4.53 (t, 1 H, J3,2 2.9 Hz, H-3),
4.50–4.36 (m, 2 H, H-6a, 6b), 3.61 (dd, 1 H,
H-2), 3.56 (s, 3 H OMe); 13C NMR (CDCl3):
l 166.21, 165.21 (2×CꢀO), 133.48, 133.00,
129.79, 129.63, 129.16, 128.47, 128.35, 128.27
(Ar), 101.43 (C-1), 70.78, 69.92, 69.50, 68.69
(C-2, 3, 4, 5), 63.77 (C-6), 57.17 (OMe).
HRMS (LSI MS): Calcd for C21H22O8+Na+
[M+Na]+, 425.12125. Found: 425.12356.
Reaction between methyl h-
D-glucopyran-
Methyl 3,4,6-tri-O-benzoyl-i- -allopyran-
D
oside (4) and diethyl azodicarboxylate.—A
suspension of 4 (1 g, 5.15 mmol) in THF (50
mL) was treated as described in General meth-
ods [PPh3 (6.45 g), DEAD (4.31 g in 10 mL
THF), benzoic acid (3.02 g)]. After 2 h of
reflux and work-up as above, the mixture was
separated by chromatography with 10:1“1:6
hexane–ether into five fractions, which were
further separated by preparative TLC or
HPLC to give 11 (0.095 g, 4.6%), 12 (0.082 g,
3.1%), 13 (0.030 g, 1.2%), 14 (0.077 g, 3.0%),
15 (0.219 g, 10.6%), 16 (0.090 g, 3.5%), 17
(0.146 g, 10.1%), 18 (0.293 g, 14.8%), 19 (0.337
g, 17.0%), 20 (0.130 g, 9.0%), and 21 (0.095 g,
4.8%).
oside (8).—Mp 177–178 °C (from toluene);
[h]D +79° (c 1.71); 1H NMR (CDCl3): l 8.10–
7.23 (m, 15 H, 3 Ph), 6.12 (t, 1 H, J3,2 3.0, J3,4
3.0 Hz, H-3), 5.41 (dd, 1 H, J4,5 9.7 Hz, H-4),
4.83 (d, 1 H, J1,2 7.9 Hz, H-1), 4.73–4.62 (m,
1 H, H-5), 4.55–4.38 (m, 2 H, H-6a, 6b), 3.90
(dd, 1 H, H-2), 3.64 (s, 3 H, OMe), 2.50 (bs, 1
13
H, OH); C NMR (CDCl3): l 166.14, 165.80,
164.93 (3×CꢀO), 133.39, 133.34, 133.08,
129.75, 129.66, 129.55, 128.92, 128.53, 128.33
(Ar), 101.94 (C-1), 70.68, 70.45, 69.96, 68.08
(C-2, 3, 4, 5), 63.53 (C-6), 57.18 (OMe).
HRMS (LSI MS): Calcd for C28H26O9+Na+
[M+Na]+, 529.14746. Found: 529.14798.
Anal. Calcd for C28H26O9: C, 66.40; H, 5.17.
Found: C, 66.18; H, 5.24.
Benzoylation of 8, 7 and 6 under standard
conditions gave 9. Similarly, benzoylation of
17 gave 18, and of 20 gave 21. New com-
pounds were fully characterized; physical and
spectral data of known compounds agreed
with the literature values.
Methyl 2,3,4,6-tetra-O-benzoyl-i- -allopyr-
D
anoside (9).—Mp 163–164 °C (from EtOH);
1
[h]D +17° (c 1.61); H NMR (CDCl3) l 8.10–
7.27 (m, 20 H, 4 Ph), 6.22 (t, 1 H, J3,2 3.1, J3,4
2.9 Hz, H-3), 5.58 (dd, 1 H, J4,5 9.7 Hz, H-4),
5.41 (dd, 1 H, J2,1 8.1 Hz, H-2), 5.11 (d, 1 H,
H-1), 4.72 (dd, 1 H, J6a,5 2.4, J6a,6b 11.4 Hz,
H-6a), 4.56 (ddd, 1 H, J5,6b 5.0 Hz, H-5), 4.49
(dd, 1 H, H-6b), 3.59 (s, 3 H, OMe); 13C
NMR (CDCl3): l 166.19, 165.18, 164.81,
164.71 (4×CꢀO), 133.49, 133.37, 133.17,
129.81, 129.72, 129.68, 129.61, 129.53, 129.32,
128.89, 128.66, 128.38, 128.26 (Ar), 100.07
(C-1), 70.78, 69.68, 69.38, 67.59 (C-2, 3, 4, 5),
Methyl 3,6-di-O-benzoyl-i- -allopyranoside
D
1
(6).—Syrup, [h]D −55° (c 2.41); H NMR
(CDCl3): l 8.12–8.03, 7.65–7.38 (m, 10 H, 2
Ph), 5.85 (t, 1 H, J3,4 3.0, J3,2 3.1 Hz, H-3),
4.72 (d, 1 H, J1,2 7.8 Hz, H-1), 4.68–4.60 (m,
2 H, H-6a, 6b), 4.11 (dt, 1 H, J5,4 9.5, J5,6a 3.5,
J5,6b 4.0 Hz, H-5), 3.93 (dd, 1 H, H-4), 3.73
13
(dd, 1 H, H-2), 3.59 (s, 3 H, OMe); C NMR
(CDCl3): l 167.08, 166.90 (2×CꢀO), 133.56,

248
M. Kim et al. / Carbohydrate Research 320 (1999) 244–249
133.47, 133.16, 133.10, 129.81, 129.74, 129.62,
129.44, 129.35, 129.28, 128.55, 128.39, 128.19
(Ar), 99.81 (C-1), 71.40, 69.28, 67.95, 67.17
(C-2, 3, 4, 5), 62.59 (C-6), 55.78 (OMe).
63.39 (C-6), 56.94 (OMe). HRMS (LSI MS):
Calcd for C35H30O10+Na+ [M+Na]+,
633.17365. Found: 633.17234. Anal. Calcd for
C35H30O10: C, 68.85; H, 4.95. Found: C, 68.77;
H, 4.86.
Methyl 3,6-di-O-benzoyl-h- -glucopyran-
D
oside (15).—Mp 135–136 °C (from EtOAc–
hexane); [h]D +135° (c 1.07); lit [8]: mp 136–
137 °C (from EtOAc), [h]D +136° (c 1
Methyl 3,6-anhydro-4-O-benzoyl-i- -galac-
D
topyranoside (10).—Syrup, [h]D−142° (c
1
2.14); H NMR (CDCl3): l 8.15–7.98, 7.67–
1
CHCl3); H NMR (CDCl3+D2O): l 8.12–
7.42 (m, 5 H, Ph), 5.21 (dd, 1 H, J4,3 5.5, J4,5
3.1 Hz, H-4), 4.80 (bs, 1 H, H-1), 4.63 (t, 1 H,
J5,6a B1, J5,6b 3.2 Hz, H-5), 4.48 (dd, 1 H, J3,2
3.6 Hz, H-3), 4.37 (dd, 1 H, J6a,6b 10.1 Hz,
H-6a), 4.02 (dd, 1 H, H-6b), 3.95 (bd, 1 H,
8.00, 7.63–7.37 (m, 10 H, 2 Ph), 5.37 (t, 1 H,
J3,2 9.5, J3,4 9.5 Hz, H-3), 4.87 (d, 1 H, J1,2 3.9
Hz, H-1), 4.74 (dd, 1 H, J6a,5 4.6, J6a,6b 12.1
Hz, H-6a), 4.59 (dd, 1 H, J6b,5 2.4 Hz, H-6b),
4.00 (ddd, 1 H, J5,4 9.9 Hz, H-5), 3.78 (dd, 1
H, H-2), 3.71 (t, 1 H, H-4).
13
H-2), 3.47 (s, 3 H, OMe); C NMR (CDCl3):
l 165.55 (CꢀO), 133.66, 133.59, 130.11,
129.61, 129.05, 128.72, 128.41 (Ar), 104.04
(C-1), 72.74, 71.83, 71.63, 71.57 (C-2, 3, 4, 5),
70.79 (C-6), 55.84 (OMe). HRMS (LSI MS):
Calcd for C14H16O6+Na+ [M+Na]+,
303.08447. Found: 303.08487.
Methyl 3,4,6-tri-O-benzoyl-h- -glucopyran-
D
oside (16).—Amorphous solid, [h]D +76° (c
1
2.26); lit [11]: [h]D +75° (c 2, CHCl3); H
NMR (CDCl3+D2O): l 8.07–7.88, 7.60–7.27
(m, 15 H, 3 Ph), 5.73 (t, 1 H, J3,2 9.5, J3,4 9.7
Hz, H-3), 5.56 (t, 1 H, J4,5 9.7 Hz, H-4), 4.94
(d, 1 H, J1,2 3.9 Hz, H-1), 4.59 (dd, 1 H, J6a,5
2.9, J6a,6b 12.1 Hz, H-6a), 4.45 (dd, 1 H, J6b,5
5.2 Hz, H-6b), 4.32 (ddd, 1 H, H-5), 3.92 (dd,
1 H, H-2), 3.54 (s, 3 H, OMe); 13C NMR
(CDCl3): l 166.73, 166.08, 165.25 (3×CꢀO),
133.34, 133.15, 133.05, 129.74, 129.62, 129.25,
128.86, 128.34, 128.25 (Ar), 99.36 (C-1), 73.90,
71.43, 69.02, 67.91 (C-2, 3, 4, 5), 63.10 (C-6),
55.71 (OMe).
Methyl 3,6-di-O-benzoyl-h- -allopyranoside
D
1
(11).—Syrup, [h]D +43° (c 0.94); H NMR
(CDCl3): l 8.17–8.02, 7.65–7.39 (m, 10 H, 2
Ph), 5.76 (t, 1 H, J3,2 3.4, J3,4 3.3 Hz, H-3),
4.83 (d, 1 H, J1,2 4.4 Hz, H-1), 4.67 (dd, 1 H,
J6a,5 4.6, J6a,6b 12.1 Hz, H-6a), 4.59 (dd, 1 H,
J6b,5 2.7 Hz, H-6b), 4.21 (ddd, 1 H, J5,4 9.9 Hz,
H-5), 3.98–3.85 (m, 1 H, H-2), 3.88 (dd, 1 H,
H-4), 3.57 (s, 3 H, OMe), 2.64 (bd, 1 H, JOH,2
9.6 Hz, OH); 13C NMR (CDCl3): l 167.30,
166.82 (2×CꢀO), 133.40, 133.16, 129.98,
129.69, 129.48, 128.46, 128.36 (Ar), 98.67 (C-
1), 72.87, 67.14, 66.66, 66.01 (C-2, 3, 4, 5),
63.77 (C-6), 56.13 (OMe). HRMS (LSI MS):
Calcd for C21H22O8+Na+ [M+Na]+,
425.12124. Found: 425.12052.
Methyl
2,3-anhydro-6-O-benzoyl-h- -al-
D
lopyranoside (17).—Mp 141–143 °C (from
EtOH); [h]D+87° (c 1.67); lit [12]: mp 140–
142 °C, [h]D +74° (c 0.3, CHCl3); 13C NMR
(CDCl3): l 166.86 (CꢀO), 133.19, 130.10,
129.67, 128.38 (Ar), 94.50 (C-1), 67.72, 65.84
(C-4,5), 64.10 (C-6), 55.69, 55.39, 53.81 (C-2,
3, OMe).
Methyl 3,4,6-tri-O-benzoyl-h- -allopyran-
D
oside (12).—Syrup, [h]D +141° (c 1.71); lit [8]:
[h]D+117° (c 1, CHCl3); 13C NMR (CDCl3):
l 166.15, 165.79, 164.90 (3×CꢀO), 133.33,
133.33, 133.25, 133.10, 129.89, 129.70, 129.63,
129.05, 128.51, 128.37, 128.27 (Ar), 98.88 (C-
1), 70.05, 67.34, 66.81, 63.57 (C-2, 3, 4, 5),
63.18 (C-6), 56.32 (OMe).
Methyl 2,3-anhydro-4,6-di-O-benzoyl-h- -
D
allopyranoside (18).—Mp 122–124 °C (from
EtOH–hexane); [h]D +202° (c 1.08); lit [13]:
mp 125–126 °C (from ether–hexane); [h]D +
199° (c 3.48, CHCl3); 13C NMR (CDCl3): l
166.09, 165.76 (2×CꢀO), 133.53, 133.05,
129.85, 129.69, 129.58, 129.07, 128.47, 128.34
(Ar), 94.54 (C-1), 68.07, 64.85 (C-4, 5), 63.52
(C-6), 55.84, 54.75, 51.39 (C-2, 3, OMe).
Methyl 2,4,6-tri-O-benzoyl-h- -galactopyr-
D
anoside (13).—Syrup, [h]D +102° (c 2.66); lit
[9]: [h]D +104° (c 1.0, CHCl3).
Methyl 2,3-anhydro-4,6-di-O-benzoyl-h- -
D
Methyl 3,4,6-tri-O-benzoyl-h- -galactopyr-
D
gulopyranoside (19).—Mp 100–101 °C (from
1
anoside (14).—Syrup, [h]D +102° (c 1.10); lit
[10]: [h]D +102° (c 1.0, CHCl3); 13C NMR
(CDCl3): l 166.14, 165.96, 165.46 (3×CꢀO),
EtOAc–hexane); [h]D −35° (c 1.26), H NMR
(C6D6): l 8.18–8.06, 7.18–6.92 (m, 10 H, 2
Ph), 5.44–5.39 (m, 1 H, H-4), 4.62 (d, 1 H, J1,2

M. Kim et al. / Carbohydrate Research 320 (1999) 244–249
249
2.9 Hz, H-1), 4.61 (dd, 1 H, J6a,5 7.9, J6a,6b 11.0
Hz, H-6a), 4.44 (ddd, 1 H, J5,6b 4.4, J5,4 1.6
Hz, H-5), 4.18 (dd, 1 H, H-6b), 3.20 (dd, 1 H,
J4,3 2.4, J3,2 3.6 Hz, H-3), 3.17 (s, 3 H, OMe),
2.84 (d, 1 H, H-2); 13C NMR (CDCl3): l
165.97, 165.70 (2×CꢀO), 133.62, 133.10,
129.88, 129.55, 129.02, 128.54, 128.44, 128.37
(Ar), 94.72 (C-1), 66.16, 65.02 (C-4, 5), 63.37
(C-6), 55.58, 51.29, 49.94 (C-2, 3, OMe). Anal.
Calcd for C21H20O7: C, 65.62; H, 5.24. Found:
C, 65.72; H, 5.26. HRMS (LSI MS) Calcd for
C21H20O7+H+ [M+H]+, 385.12873. Found:
385.12665.
H-1), 4.89 (dd, 1 H, H-2), 4.62 (dd, 1 H, J6a,5
6.6, J6a,6b 11.2 Hz, H-6a), 4.49 (dd, 1 H, J6b,5
5.5 Hz, H-6b), 4.11 (ddd, 1 H, J5,4 0.9 Hz,
H-5), 3.12 (dd, 1 H, J3.2 1.1, J3,4 4.0 Hz, H-3),
2.95 (s, 3 H, OMe), 2.82 (dd, 1 H, H-4); 13C
NMR (CDCl3): l 166.18, 165.44 (2×CꢀO),
133.41, 133.14, 129.81, 129.67, 128.42, 128.38
(Ar), 94.40 (C-1), 66.26, 64.05 (C-2, 5), 64.02
(C-6), 55.97 (OMe), 51.24, 49.84 (C-3, 4).
HRMS (LSI MS): Calcd for C21H20O7+H+
[M+H]+, 385.12873. Found: 385.12919.
Methyl 3,4-anhydro-6-O-benzoyl-h- -galac-
D
Acknowledgements
topyranoside (20).—Mp 122–123 °C (from
1
EtOH–hexane); [h]D +39° (c 0.59); H NMR
Support of this work by Grant No. 3 TO9A
066 12 from the State Committee for Scientific
Research (KBN) is gratefully acknowledged.
(CDCl3): l 8.12–8.00, 7.62–7.38 (m, 5 H, Ph),
4.72 (d, 1 H, J1,2 4.7 Hz, H-1), 4.59–4.51 (m,
2 H, H-6a, 6b), 4.31 (bt, 1 H, J5,6a 6.0, J5,6b
6.2, J5,4B1 Hz, H-5), 3.87 (dd, 1 H, J2,OH 10.4
Hz, H-2), 3.49 (s, 3 H, OMe), 3.34–3.26 (m, 2
References
1
H, H-3, 4), 2.51 (d, 1 H, OH); H NMR
(C6D6): l 8.19–8.11, 7.18–6.95 (m, 5 H, Ph),
4.50 (dd, 1 H, J6a,5 6.7, J6a,6b 11.2 Hz, H-6a),
4.43 (dd, 1 H, J6b,5 5.5 Hz, H-6b), 4.30 (d, 1
H, J1,2 4.6 Hz, H-1), 3.96 (ddd, 1 H, J5,4 0.7
Hz, H-5), 3.78 (bd, 1 H, J2,3 B1 Hz, H-2),
3.04 (dd, 1 H, J3,4 4.0 Hz, H-3), 2.86 (s, 3 H,
OMe), 2.72 (dd, 1 H, H-4); 13C NMR
(CDCl3): l 166.20 (CꢀO), 133.16, 129.66,
128.39 (Ar), 95.92 (C-1), 64.19, 63.65 (C-2, 5),
64.03 (C-6), 55.92 (OMe), 53.12, 50.11 (C-3,
4). HRMS (LSI MS): Calcd for C14H16O6+
H+ [M+H]+, 281.10251. Found: 281.10346.
Anal. Calcd for C14H16O6: C, 59.99; H, 5.76.
Found: C, 59.85; H, 5.98.
[1] D.C. Baker, D. Horton, Ch.G. Tindall Jr., Carbohydr.
Res., 24 (1972) 192–197.
[2] R. Ahluwahlia, S.J. Angyal, M.H. Randall, Carbohydr.
Res., 4 (1967) 478–485.
[3] K. Weinges, S. Haremsa, W. Maurer, Carbohydr. Res.,
164 (1987) 453–458.
[4] G. Grynkiewicz, Rocz. Chem., 50 (1976) 1449–1451.
[5] G. Grynkiewicz, Pol. J. Chem., 53 (1979) 2501–2515.
[6] I. Dancy, L. Laupichler, P. Rollin, J. Thiem, Liebigs
Ann. Chem., (1993) 343–350.
[7] A.C. Richardson, Carbohydr. Res., 10 (1969) 395–402.
[8] Y. Ishido, N. Sakairi, M. Sekiya, M. Nakazaki, Carbo-
hydr. Res., 97 (1981) 51–80.
[9] L.A. Mulard, P. Kovac, C.P.J. Glaudemans, Carbohydr.
Res., 251 (1994) 213–232.
[10] L.A. Mulard, C.P.J. Glaudemans, Carbohydr. Res., 274
(1995) 209–222.
[11] J.J. Willard, J. Sadowski, W. Vitale, Can. J. Chem., 41
(1963) 1223–1230.
Methyl 3,4-anhydro-2,6-di-O-benzoyl-h- -
D
[12] N.A.L. Al-Masoudi, N.A. Hughes, J. Chem. Soc., Perkin
Trans., 1 (1987) 2061–2068.
[13] R.W. Jeanloz, D.A. Jeanloz, J. Am. Chem. Soc., 80
(1958) 5692–5697.
galactopyranoside (21).—Syrup, [h]D +34° (c
1
1.22); H NMR (C6D6): l 8.22–8.10, 7.20–
6.95 (m, 10 H, 2 Ph), 5.13 (d, 1 H, J1,2 4.4 Hz,
.