Regio- and stereochemical controlled koenigs-knorr-type monoglycosylation of secondary hydroxy groups in carbohydrates utilizing the high site recognition ability of organotin catalysts

Article abstract of DOI:10.1002/adsc.201300414

The catalytic regio- and stereoselective monoglycosylation of carbohydrates using organotin catalysts is demonstrated. The one-step reaction affords various oligosaccharides linked at the secondary hydroxy group in high chemical yield and good regio- and stereoselectivities. The regioselectivity of the glycosylation is shown to depend on the spatial arrangement of the hydroxy groups in the carbohydrates. Copyright

Full text of DOI:10.1002/adsc.201300414

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DOI: 10.1002/adsc.201300414
Regio- and Stereochemical Controlled Koenigs–Knorr-Type
Monoglycosylation of Secondary Hydroxy Groups in
Carbohydrates Utilizing the High Site Recognition Ability of
Organotin Catalysts
Wataru Muramatsua,* and Hirofumi Yoshimatsua
a
Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, Nagasaki 852-8521, Japan
Fax : (+81)-95-819-2476; phone: (+81)-95-819-2431; e-mail: muramatu@nagasaki-u.ac.jp
Received: May 10, 2013; Revised: July 6, 2013; Published online: && &&, 0000
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201300414.
Abstract: The catalytic regio- and stereoselective
monoglycosylation of carbohydrates using organo-
tin catalysts is demonstrated. The one-step reaction
affords various oligosaccharides linked at the secon-
dary hydroxy group in high chemical yield and
good regio- and stereoselectivities. The regioselec-
tivity of the glycosylation is shown to depend on
the spatial arrangement of the hydroxy groups in
the carbohydrates.
lective functionalization of polyols remains one of the
most fundamental challenges. The non-enzymatic re-
gioselective functionalization of the secondary hy-
droxy groups in carbohydrates is of particular interest
because of the difficulty in functionalizing one specific
hydroxy group from among the multiple groups pres-
ent. Over the last few decades, various catalytic meth-
ods for the regioselective functionalizations including
acylation and sulfonylation of carbohydrates have
been developed.[6] In the case of glycosylation, Cruza-
do and a few groups reported the regioselective 6-O-
glycosylation of carbohydrates by using stoichiometric
quantities of Bu2SnO.[7] However, we feel that the ad-
dition of Bu2SnO is not necessary for 6-O-glycosyla-
tion because the nucleophilicity of primary hydroxy
group is basically higher than that of secondary hy-
Keywords: glycosylation; oligosaccharides; organo-
tin catalysts; regioselectivity; stereoselectivity
Oligosaccharide-containing glycoconjugates such as droxy group.[8] Most recently, Taylor reported the re-
glycoproteins, glycolipids, and proteoglycans are ubiq- gioselective glycosylation of the secondary hydroxy
uitous in nature and play an important role in a wide groups in carbohydrates by using borinic acid as the
range of biological processes, e.g., in modulating the catalyst. The method afforded high regio- and stereo-
activity, dynamic stability, and intracellular transpor- selectivities for the synthesis of oligosaccharides.
tation of proteins.[1] Glycoconjugates are major com- However, this method is not applicable to those car-
ponents of the outer membrane of mammalian cells, bohydrates bearing free primary hydroxy groups.[9] To
and the oligosaccharide units play fundamental roles the best of our knowledge, a widely applicable cata-
in intercellular processes including infection, cell lytic method for the regioselective glycosylation of
growth, and cell-cell adhesion, etc.[2] Since the recent secondary hydroxy groups in a variety of carbohy-
identification of the vital roles played by the oligosac- drates has not been reported so far.[7–11] Herein, we
charide units in biologically interesting glycosides present the first catalytic regio- and stereoselective
such as vancomycin and calicheamicin, there has been Koenigs–Knorr-type monoglycosylation of secondary
increased interest in the synthesis, biomechanism, and hydroxy groups in carbohydrates by using organotin
biological activities of these glycosides.[3] Carbohy- dichloride.
drate-based surfactants with an oligosaccharide as the
The effects of various reaction parameters and con-
polar head group are widely used in industry. The am- ditions on the efficiency of glycosylation at the C-3
phiphilic surfactants help in the solubilization of OH of methyl a-d-mannopyranoside are summarized
membrane proteins by interacting with the hydropho- in Table 1. After a series of optimization experiments,
bic sites of the proteins.[4]
we found that selective glycosylation at the C-3 OH
Polyols are used as building blocks for the synthesis of methyl a-d-mannopyranoside proceeded most effi-
of natural products and new drugs.[5] However, the se- ciently in the presence of Ph2SnCl2 (10 mol%),
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Table 1. Regio- and stereoselective glycosylation of methyl a-d-mannopyranoside catalyzed by Ph2SnCl2.
Entry
Variation from the “standard” conditions
Yield [%]
1
none
99
2
3
10 mmol-scale of a-d-Man
no Ph2SnCl2
99
0
4
5
no Ag2O
no DMBPY
0
46 (2)[a]
6
7
8
9
Ph2SnCl2 (5 mol%), 48 h
Me2SnCl2, instead of Ph2SnCl2
Bu2SnCl2, instead of Ph2SnCl2
Oc2SnCl2, instead of Ph2SnCl2
Ph2SnO, instead of Ph2SnCl2
Ph2SnS, instead of Ph2SnCl2
PhSnCl3, instead of Ph2SnCl2
Ph3SnCl, instead of Ph2SnCl2
Ph4Sn, instead of Ph2SnCl2
AgO, instead of Ag2O
62
40
4
5
40
75
93
66
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
63
59
76
Ag2CO3, instead of Ag2O
AgOTf, instead of Ag2O
AgClO4, instead of Ag2O
AgF, instead of Ag2O
12 (29)[a]
12 (34)[a]
<1
PEMP,[c] instead of DMBPY
pyridine,[c] instead of DMBPY
2,4,6-collidine,[c] instead of DMBPY
toluene, instead of CH3CN
DCM, instead of CH3CN
THF, instead of CH3CN
1,4-dioxane, instead of CH3CN
H2O, instead of CH3CN
a-d-Glc-F, instead of a-d-Glc-Br
a-d-Glc-Cl, instead of a-d-Glc-Br
a-d-Glc-SPh, instead of a-d-Glc-Br
71
74
77
<1
26 (2)[a]
60
67
15
0 (<1)[b]
0 (53)[b]
0 (2)[b]
[a]
The yield of the orthoester.
The reaction was carried out at 608C.
1.5 equiv. of base was added.
[b]
[c]
2,3,4,6-tetraacetyl-a-d-glucopyranosyl
bromide the use of other dialkyltin dichlorides instead of
(1.5 equiv.), Ag2O (1.5 equiv.), and 5,5’-dimethyl-2,2’- Ph2SnCl2 (entries 7–9). When the glycosylation was
bipyridyl (DMBPY, 0.75 equiv.) in CH3CN at 358C conducted with 10 mol% of Ph2SnO, Ph2SnS or
(entry 1; 99% yield and no regio- and stereoisomers). Ph3SnCl instead of Ph2SnCl2, the desired disaccharide
When the reaction was carried out on a 10 mmol 1 was isolated in moderate yields (entries 10, 11 and
scale, use of the catalyst for regioselective glycosyla- 13). PhSnCl3 could be employed in place of Ph2SnCl2,
tion resulted in excellent yield and selectivity at the expense of a slight decrease in chemical yield
(entry 2; 99% yield and no regio- and stereoisomers). (entry 12; 93% yield). Contrary to our expectations,
In the absence of Ph2SnCl2 or Ag2O, the reaction did the use of Ph4Sn as a catalyst afforded 1 in 63% yield
not afford any product including the desired disac- without formation of the regioisomers such as a Ac-b-
charide 1 (entries 3 and 4). In the absence of d-Glc-(1!6)-a-d-Man-OMe (entry 14). The identity
DMBPY, 1 was obtained in 46% yield and the corre- of the Ag salt used as the promoter was crucial to the
sponding orthoester[7c,9,11a] was formed in 2% yield success of this transformation. When Ag2O was re-
(entry 5). The use of smaller amounts of catalyst af- placed with AgO or Ag2CO3, the yield of 1 decreased
forded 1 in lower yield (entry 6; 62% yield), as did drastically (entries 15 and 16). On using silver(I) salts
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Regio- and Stereochemical Controlled Koenigs–Knorr-Type Monoglycosylation
Table 2. Regio- and stereoselective glycosylation of various carbohydrates.[a]
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with stronger Lewis acidity, such as AgOTf and (entries 1 and 3–4). When phenyl a-d-thiomannopyra-
AgClO4, 1 was obtained in only 12% yield, while the noside was used as the glycosyl acceptor, the reaction
major product was the corresponding orthoester with afforded the corresponding disaccharide 8 in 81%
yields of 29–34% (entries 17 and 18). AgF did not act yield (entry 7). Based on these results, this catalytic
as
a promoter under these reaction conditions system was used to differentiate between the primary
(entry 19). The use of 1,2,2,6,6-pentamethylpiperidine and secondary hydroxy groups for a wide range of
(PEMP), which we previously used in the regioselec- carbohydrates acting as a glycosyl acceptor. Monogly-
tive functionalization of carbohydrates,[6d,e] instead of cosylation was observed only at cis-1,2-diol moieties,
DMBPY gave 1 in 71% yield (entry 20). The reac- with an equatorial OH in derivatives of mannopyra-
tions with pyridine and 2,4,6-collidine also afforded noside (entry 9), galactopyranoside (entries 10–13 and
the product in good yield (entries 21 and 22). The re- 16), fucopyranoside (entries 14–15) and arabinopyra-
activity of these bases was comparable to that of noside (entry 17) in high yield and excellent regiose-
DMBPY. However, DMBPY by virtue of its bulkiness lectivity.
prevented the formation of trisaccharides. In less
Importantly, the result corresponding to entry 1
polar solvents such as toluene and DCM, the yields of clearly proved that this catalysis proceeded with ex-
1 were markedly decreased (entries 23 and 24). On cellent stereochemical control via an direct SN2-type
the other hand, the use of THF and 1,4-dioxane as inversion mechanism, and not by neighboring group
the solvent in place of CH3CN resulted in only participation. On the other hand, the catalytic regio-
a slight decrease in chemical yield (entries 25 and 26). selective glycosylation of methyl a-d-glucopyranoside
Surprisingly, the catalytic reaction in H2O afforded with 2,3,4,6-tetrabenzoyl-a-d-glucopyranosyl bromide
1 in 15% yield along with deacylated 1 (entry 27). selectively afforded Bz-b-d-Glc-(1!3)-a-d-Glc-OMe
However, the formation of non-negligible amounts of 9a as the major product (entry 8)[12] and not the ex-
trisaccharides (3–47% yield) could not be avoided pected disaccharide, Bz-b-d-Glc-(1!2)-a-d-Glc-OMe
when these silver salts, bases, and solvents under the 9b.[10c] Furthermore, all the physical and spectroscopic
present conditions (entries 17, 18, and 20–25). Next, data pertaining to disaccharide 19, formed by depro-
we examined the scope of the catalytic regioselective tection of the Bz groups in 9a, were in perfect accord
monoglycosylation for various leaving groups of the with those of the previously reported methyl a-d-lam-
glycosyl donor and attempted to find the best reaction inarabioside.[13] Then, when 9b was treated under the
conditions. Unfortunately, in the case of a-d-glucopyr- same reaction conditions, we observed 1,2-shift of the
anosyl fluoride and a-d-thioglucopyranoside as the glycosyl donor to transform 9b into 9a. It seems that
glycosyl donor, the glycosylation did not give any 9a is maybe thermodynamically more stable. Howev-
products including the desired disaccharide 1 under er, the mechanism of 1,2-shift is still unclear.
the conditions (entries 28 and 30). In contrast, a-d-
glucopyranosyl chloride could act as good substitute acceptors in this catalytic glycosylation can be ex-
for a-d-glucopyranosyl bromide (entry 29). plained as follows (Scheme 1). Coordination of
The regio- and stereoselectivity of these glycosyl
Based on the optimization studies, the functional Ph2SnCl2 with the cis-diol moieties in these glycosyl
group tolerance of the glycosyl donor is discussed acceptors is favored after moving freely among diol
below. Galactopyranosyl, arabinopyranosyl and fuco- moieties. As the coordination of metal ions increases
pyranosyl halides underwent regio- and stereoselec- the acidity of the hydroxy groups, even a weak base
tive glycosylation (entries 2 and 5–6, Table 2). Fur- such as DMBPY is sufficient to induce deprotonation.
thermore, substrates bearing benzyl, amino and ester Then, the an axial-H adjacent to the reacting axial-
groups were tolerated in the glycosylation reaction OH in the cis-1,2-diol moiety restricts the approach of
[a]
For the reaction conditions as a standard, see Table 1.
The reaction was carried out using the glycosyl chloride as a donor.
The reaction was carried out at 608C.
Isolated yield of the regioisomer.
In THF/1,4-dioxane (1:2).
In 1,4-dioxane.
Ag2O (2.0 equiv.) was used.
The glycosyl acceptor was recovered in 6–31% yield.
[b]
[c]
[d]
[e]
[f]
[g]
[h]
[i]
In THF.
[j]
The reaction was carried out at 508C.
DMBPY (0.65 equiv.) was used.
Glycosyl donor (1.0 equiv.) and glycosyl acceptor (1.5 equiv.) were used.
The reaction was carried out at 458C.
[k]
[l]
[m]
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Regio- and Stereochemical Controlled Koenigs–Knorr-Type Monoglycosylation
Scheme 1. Plausible explanation of the regio- and stereoselective glycosylation of carbohydrates.
DMBPY (1,3-diaxial interaction). Hence, the most ac- in THF at 308C for 24 h gave the oligosaccharide 20
cessible hydroxy group, which is the equatorial-OH, in 70% yield. Then deprotection of the Ac groups in
can be attacked by DMBPY. The glycosylation reac- 20 was accomplished upon treatment with NaOMe in
tion, which proceeds via intermediate A generated MeOH to provide compound 21 in 89% yield. The
from the coordination of the glycosyl donor with compound 21 showed mp 228–2318C, [a]1D9: +12.6 (c
Ag2O, results in 1 with stereoinversion at the anome- 0.51, EtOH) {lit[14a] mp 220–2318C, lit[14b] [a]D20: +12 (c
ric position of the glycosyl donor. In contrast, the use 1.08, EtOH)}. Additionally, the physical and spectro-
of Ag(I) salts with stronger Lewis acidity such as scopic data for 21 agreed well with those for the bio-
AgOTf yields the orthoester via the intermediate B. active cardiac glycoside, deslanoside (deacetyl-lanato-
Another possible mechanism is via concerted reac- side C),[15] obtained by methanolysis[16] of an Ac
tion. The result obtained when using Ph4Sn as the cat- group at C-3’’’ in commercially available lanatoside C
alyst (entry 14, Table 1) indicates that the nucleophilic (Scheme 2).
substitution by the equatorial OH and the deprotona-
In conclusion, a catalytic one-step process for the
tion at the equatorial-OH may occur concertedly. A monoglycosylation of secondary hydroxy group in car-
similar mechanism for the SN2-type glycosylation was bohydrates with high yield and excellent regioselectiv-
proposed by Taylor.[9]
ity was developed. This facile methodology can be ap-
Catalytic regioselective functionalization of natural plied to a wide range of carbohydrates, including
products containing multiple hydroxy groups has at- those containing highly reactive free primary hydroxy
tracted much interest in recent years. For instance, groups. This significantly expands the scope of this re-
Kawabata and Taylor recently reported regioselective action to include a great variety of oligosaccharides
acylation and glycosylation of cardiac glycosides, re- without the formation of regioisomers in the mini-
spectively, with excellent yields and selectivities.[5d,f] mum number of steps. The regio- and stereoselectivity
Therefore, we applied our protocol to the regio- and of the glycosylation depend on the spatial arrange-
stereoselective monoglycosylation of a naturally oc- ment of the hydroxy groups in the carbohydrate. The
curring compound containing five secondary hydroxy proposed reaction allows for the direct functionaliza-
groups and one tertiary hydroxy group. Treatment of tion of natural products including carbohydrates and
digoxin with 2,3,4,6-tetraacetyl-a-d-glucopyranosyl provides new insight into polyol-metal ion interaction
bromide (2.0 equiv.), Ag2O (1.5 equiv.), and DMBPY and its activation process. The scope, applications,
(0.75 equiv.) in the presence of Ph2SnCl2 (10 mol%)
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Scheme 2. Regio- and stereoselective glycosylation of digoxin.
and a Grant-in-Aid for Young Scientists (B) (24790014) from
the Ministry of Education, Culture, Sports, Science and Tech-
nology, Japan.
and mechanism of this reaction are currently under
investigation.
Experimental Section
References
Typical Procedure
[1] a) A. Varki, Glycobiology 1993, 3, 97; b) R. A. Dewk,
Chem. Rev. 1996, 96, 683; c) E. OꢁConner, B. Imperiali,
Chem. Biol. 1996, 3, 803; d) L. Ellgaard, M. Molinari,
A. Helenius, Science 1999, 286, 1882; e) R. F. Service,
Science 2012, 338, 321.
[2] a) P. R. Crocker, T. Feizi, Curr. Opin. Struct. Biol. 1996,
6, 679; b) M. Fukuda, Cancer Res. 1996, 56, 2237;
c) G. S. Kansas, Blood 1996, 88, 3259; d) Y. J. Kim, A.
Varki, Glycoconjugate J. 1997, 14, 569; e) A. J. Varki,
Clin. Invest. 1997, 99, 158.
[3] a) K. C. Nicolaou, B. Smith, J. Pastor, Y. Watanabe,
D. S. Weinstein, Synlett 1997, 401; b) C. Thompson, M.
Ge, D. Kahne, J. Am. Chem. Soc. 1999, 121, 1237; c) M.
Ge, Z. Chen, R. Onisgi, J. Kohler, L. L. Silver, R.
Kerns, S. Fukuzawa, C. Thompson, D. Kahne, Science
1999, 284, 507; d) K. C. Nicolaou, H. J. Mitchel, N. F.
Jain, N. Winssinger, R. Hughes, T. Bando, Angew.
Chem. 1999, 111, 253; Angew. Chem. Int. Ed. 1999, 38,
240.
After stirring the mixture of methyl a-d-mannopyranoside
(97.1 mg, 0.5 mmol) and diphenyltin dichloride (17.2 mg,
0.05 mmol) in CH3CN (10 mL) in a brown vial at room tem-
perature for 10 min, silver oxide (173.8 mg, 0.75 mmol), 5,5’-
dimethyl-2,2’-bipyridyl (69.1 mg, 0.375 mmol) and 2,3,4,6-
tetra-O-acetyl-a-d-glucopyranosyl
bromide
(308.4 mg,
0.75 mmol) were added to the suspension at room tempera-
ture. After stirring vigorously for 24 h at 358C, the reaction
mixture was cooled to room temperature. The reaction mix-
ture was quenched with a few drops of saturated aqueous
NH4Cl, diluted with chloroform/acetone (1/1), and then fil-
tered to remove insoluble salts. After the solution was
evaporated, the residue was purified by SiO2 column chro-
matography (chloroform/methanol 99/1–90/10) to give
methyl 3-O-(2’,3’,4’,6’-tetra-O-acetyl-b-d-glucopyranosyl)-a-
d-mannopyranoside 1 as a white solid; yield: 259.2 mg
(99%).
[4] a) T. VanAken, S. Foxall-Vanaken, S. Castleman, S. Fer-
guson-Miller, Methods in Enzymology 1986, 125, 27;
b) S. Izawa, Y. Sakai-Tomita, K. Kinomura, S. Kitaza-
wa, M. Tsuda, T. Tsuchiya, J. Biochem. 1993, 113, 573;
c) T. Tsukihara, H. Aoyama, E. Yamashita, T. Tomiza-
ki, H. Yamaguchi, K. Shinzawa-Itoh, R. Nakashima, R.
Acknowledgements
Support has been provided by Special Coordination Funds
for Promoting Science and Technology from the Ministry of
Education, Culture, Sports, Science and Technology, Japan,
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asc.wiley-vch.de
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ÝÝ
These are not the final page numbers!

Regio- and Stereochemical Controlled Koenigs–Knorr-Type Monoglycosylation
Yaona, S. Yoshikawa, Science 1995, 269, 1069; d) S.
Iwata, C. Ostermeier, B. Ludwig, H. Michel, Nature
1995, 376, 660; e) C. Lange, J. H. Nett, B. L. Trumpow-
er, C. Hunte, EMBO J. 2001, 20, 6591.
groups using stoichiometric quantities of Lewis acids
with moderate yield and selectivity has been devel-
oped. See; a) K. Oshima, T. Yamauchi, M. Shimomura,
S. Miyauchi, Y. Aoyama, Bull. Chem. Soc. Jpn. 2002,
75, 1319; b) E. Kaji, K. Shibayama, K. In, Tetrahedron
Lett. 2003, 44, 4881; c) E. Kaji, T. Nishino, K. Ishige, Y.
Ohya, Y. Shirai, Tetrahedron Lett. 2010, 51, 1570; d) T.
Nishino, M. Ohya, R. Murai, T. Shirahata, D. Yamamo-
to, K. Makino, E. Kaji, Heterocycles 2012, 84, 1123.
[11] A regioselective glycosylation of the secondary hydroxy
group in partially protected carbohydrates has been de-
veloped. See: a) K. Oshima, Y. Aoyama, J. Am. Chem.
Soc. 1999, 121, 2315; b) P. G. Evans, H. M. I. Osborn,
W. G. Suthers, Tetrahedron Lett. 2002, 43, 7855; c) K. N.
Jayaprakash, B. Fraser-Reid, Org. Lett. 2004, 6, 4211;
d) P. Cmoch, Z. Pakulski, Tetrahedron: Asymmetry
2008, 19, 1494; e) J. Lawandi, S. Rocheleau, N. Moitess-
ier, Tetrahedron 2011, 67, 8411; f) Y. Zhang, D. Dong,
M. Sollogoub, Y. Zhang, Eur. J. Org. Chem. 2011, 7133.
[12] The catalytic regioselective glycosylation at 508C af-
forded Bz-b-d-Glc-(1!3)-a-d-Glc-OMe 9a in 80%
yield with a trace amount of Bz-b-d-Glc-(1!2)-a-d-
Glc-OMe 9b. At 308C, the catalysis afforded 9b as
a major product in poor yield. The two disaccharides
were easily separable by silica gel chromatography.
[13] a) N. K. Kochetkov, A. J. Khorlin, A. F. Bochkov, Tetra-
hedron 1967, 23, 693; b) K. Takeo, Carbohydr. Res.
1979, 77, 245; c) V. Chiffoleau-Giraud, P. Spangenberg,
M. Dion, C. Rabiller, Eur. J. Org. Chem. 1999, 757;
d) H. C. Winter, S. Oscarson, R. Slꢂttegard, M. Tian,
I. J. Goldstein, Glycobiology 2005, 15, 1043.
[5] For examples, see: a) Y. Zhao, J. Rodrigo, A. H. Hov-
eyda, M. L. Snapper, Nature 2006, 443, 67; b) C.-C.
Wang, J.-C. Lee, S.-Y. Luo, S. S. Kulkarni, Y.-W. Huang,
C.-C. Lee, K.-L. Chang, S.-C. Hung, Nature 2007, 446,
896; c) P. A. Jordan, S. J. Miller, Angew. Chem. 2012,
124, 2961; Angew. Chem. Int. Ed. 2012, 51, 2907; d) Y.
Ueda, K. Mishiro, K. Yoshida, T. Furuta, T. Kawabata,
J. Org. Chem. 2012, 77, 7850; e) B. C. Wilcock, B. E.
Uno, G. L. Bromann, M. J. Clark, T. M. Anderson,
M. D. Burke, Nature Chem. 2012, 4, 996; f) T. M. Beale,
M. S. Taylor, Org. Lett. 2013, 15, 1358.
[6] For examples, see: a) M. J. Martinelli, R. Vaidyanathan,
J. M. Pawlak, N. K. Nayyar, U. P. Dhokte, C. W.
Doecke, L. M. Zollars, E. D. Moher, V. V. Khau, B.
ˇ
Kosmrlj, J. Am. Chem. Soc. 2002, 124, 3578; b) T. Ka-
wabata, W. Muramatsu, T. Nishio, T.; Shibata, H.
Schedel, J. Am. Chem. Soc. 2007, 129, 12890; c) Y.
Demizu, Y. Kubo, H. Miyoshi, T. Maki, Y. Matsumura,
N. Moriyama, O. Onomura, Org. Lett. 2008, 10, 5075;
d) W. Muramatsu, S. Tanigawa, Y. Takemoto, H. Yoshi-
matsu, O. Onomura, Chem. Eur. J. 2012, 18, 4850;
e) W. Muramatsu, J. Org. Chem. 2012, 77, 8083; f) D.
Lee, M. S. Taylor, Synthesis 2012, 44, 3421.
[7] a) C. Cruzado, M. Bernabe, M. Martin-Lomas, Carbo-
hydr. Res. 1990, 203, 296; b) P. J. Garegg, J.-L. Maloisel,
S. Oscarson, Synthesis 1995, 409; c) E. Kaji, N. Harita,
Tetrahedron Lett. 2000, 41, 53; d) A. Maggi, R.
Madsen, Eur. J. Org. Chem. 2013, 2683.
[8] For examples, see: a) R. K. P. Kartha, M. Kiso, A. Ha-
segawa, H. J. Jennings, J. Chem. Soc. Perkin Trans.
1 1995, 3023; b) S. Hanessian, Chem. Rev. 2000, 100,
4443; c) S. Malik, A. Sharma, R. K. P. Kartha, Trends
Carbohydr. Res. 2009, 1, 36.
[14] a) The data were obtained from United States Pharma-
copeial Convention Inc; b) G. W. A. Milne, Drugs: Syn-
onyms & Properties; Ashgate, 2000.
[15] a) W. L. Miller, K. R. Bailey, S. A. Weston, J. C. Bur-
nett Jr, R. J. Rodeheffer, Eur. J. Heart Failure 2002, 4,
63; b) L. Zhang, M. He, Y. Zhang, N. Nilubol, M. Shen,
E. Kebebew, J. Clin. Endocrinol. Metab. 2012, 97,
E319.
[9] C. Gouliaras, D. Lee, L. Chan, M. S. Taylor, J. Am.
Chem. Soc. 2011, 133, 13926.
[10] A regioselective glycosylation of secondary hydroxy
group in carbohydrates bearing free primary hydroxy
´
´
[16] B. Pekic, D. Miljkovic, Planta Med. 1975, 27, 178.
Adv. Synth. Catal. 0000, 000, 0 – 0
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COMMUNICATIONS
8 Regio- and Stereochemical Controlled Koenigs–Knorr-Type
Monoglycosylation of Secondary Hydroxy Groups in
Carbohydrates Utilizing the High Site Recognition Ability
of Organotin Catalysts
Adv. Synth. Catal. 2013, 355, 1 – 8
Wataru Muramatsu,* Hirofumi Yoshimatsu
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