An Alternative Method for the Selective Reduction of Unsaturated Nucleoside Azides to the Amines

Adachi, Takeshi; Yamada, Yoshihisa; Inoue, Ichizo; Saneyoshi, Mineo

doi:10.1055/s-1977-24270

Cited by 150 publications

(25 citation statements)

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“…and low yield of the conversion 6 + 7 Ǟ 8 prompted us to prepare the disaccharide donors 8 and 18 from the known diazido disaccharide 13 [19,24] (Scheme 2). Accordingly, after selective reduction [28] of 13 (Ǟ 14), followed by amidation with 2,4-di-O-acetyl-3-deoxy--glycero-tetronic acid [13] (14 Ǟ 15), esterification of 15 with levulinic acid in the presence of EDAC/ 4-Dimethylaminopyridine provided the disaccharide thioglycoside 8 (82 %) in three steps. A similar synthetic scheme was applied to prepare the 2-O-methylated disaccharide 18.…”

Section: Resultsmentioning

confidence: 99%

Glycosylation under Thermodynamic Control: Synthesis of the Di‐ and the Hexasaccharide Fragments of the O‐SP of Vibrio Cholerae O:1 Serotype Ogawa from Fully Functionalized Building Blocks

Adamo

Kòváč

2007

Eur J Org Chem

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The known 5-(methoxycarbonyl)pentyl α-glycoside of the hexasaccharide of the O-SP of Vibrio cholerae O:1, serotype Ogawa 31 was newly prepared from side-chain-equipped disaccharide building blocks. The intermediate tetrasaccharide 25 was prepared from the disaccharide glycosyl acceptor 11 and the (1Ǟ2)-linked disaccharide thioglycoside glycosyl donor 8, having a (non-participating) saccharide moiety at C-2 in the downstream end. When performed conventionally (at room or at sub 0°C temperatures), glycosylations with 11, carried out without anchimeric assistance, showed poor stereoselectivity but the formation of the 1,2-trans-glycosidic linkage could be markedly improved through thermodynamic control. This synthetic strategy towards 31 was more efficient than the step-wise approach, which was based

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Section: Resultsmentioning

confidence: 99%

Glycosylation under Thermodynamic Control: Synthesis of the Di‐ and the Hexasaccharide Fragments of the O‐SP of Vibrio Cholerae O:1 Serotype Ogawa from Fully Functionalized Building Blocks

Adamo

Kòváč

2007

Eur J Org Chem

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“…hydrogen sulphide (28,29) to provide the amine 14. The crude amine was converted to the acetylated phthalimido glycoside 15 in 70% overall yield under previously reported conditions (29).…”

Section: Discussion Of Resultsmentioning

confidence: 99%

Synthesis of tri- and tetrasaccharide haptens related to the Asialo forms of the gangliosides G_M2 and G_M1

Sabesan¹,

Lemieux²

1984

Can. J. Chem.

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SUBRAMANIAM SABESAN and RAYMOND U. LEMIEUX. Can. J. Chem. 62, 644 (1984) Synthesis of PDG~INA~(I+~)PDG~~(~+~)PDG~C-O(CH~)~COOCH, (21) and PDGal(l+3)PDGalNAc(1+4)P~Gal-(~+~)PDG~C-O(CH~)~COOCH~ (33) are presented starting from PDG~I(~+~)PDG~c-O(CH~)~COOCH, (1) and ~-galactose. Improvements in the preparations of D-galactal triacetate (7) and tri-O-acetyl-2-azido-2-deoxy-a-~-galactopyranosyl bromide (11) are reported. The syntheses proceeded by way of the tri-0-acetyl-2-deoxy-2-phthalimido-P-D-galactopyranosyl and 4,6-di-0-acetyl-3-0-(tetra-O-acetyl-~~-galactopyranosyl)-2-deoxy-2-phthalimido--~-galactopyranosy bromides (18 and 30), which, in turn, were prepared from the corresponding ally1 glycosides (15 and 23). The I3C chemical shifts for the tri-and tetrasaccharide portions of 21 and 33 are assigned from the chemical shifts that were observed for the carbon atoms in the disaccharides which make up these structures. The trisaccharide (21) On rapporte des amtliorations aux prtparations du triacetate de D-galactal (7) et du bromure de tri-0-acttyl azido-2 dtoxy-2 cr-D-galactopyrannosyle. Les synthkses impliquent la prtparation des bromures de tri-0-acetyl dtoxy-2 phthalimido-2 P-D-galactopyrannosyle et de di-0-acttyl-4,6 0-(tttra-0-acttyl P-D-galactopyrannosy1)-3 dtoxy-2 phthalimido-2 P-~-galactopyrannosyle (18 et 30) qui sont eux-m&mes prtparts h partir des glycosides allyliques correspondants (15 et 23). On a attribut les dtplacements chimiques du "C des portibns tri-et tttrasaccharidiques des composts 21 et 33 en se basant sur les dtplacements chimiques observts pour les atomes de carbones des disaccharides qui composent ces structures. Le trisaccharide (21) n'inhibe que trks faiblement ]'agglutination des cellules rouges A humaines par la lectine de Dolichos biflorus. Le tttrasaccharide 33 est inactif.[Traduit par le journal]

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“…Transesterification afforded intermediates 10, 16, and 20 containing only azido and benzyl protecting groups. The former were converted to amines by mild H2S reduction (16) and these were in turn N-formylated by methyl formate, used in solvent quantities (17,18) to yield 12, 17, and 21. Attempts to reduce the azido group by hydrogenation and to simultaneously remove benzyl ether residues were unsuccessful.…”

Section: Setmentioning

confidence: 99%

Synthetic antigenic determinants of the Brucella A polysaccharide: A disaccharide thioglycoside for block synthesis of pentasaccharide and lower homologues of α1,2-linked 4,6-dideoxy-4-formamido-α-D-mannose

Peters¹,

Bundle²

1989

Can. J. Chem.

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. Can. J. Chem. 67, 491 (1989). Methyl glycosides 13, 18, and 22, which represent potential antigenic determinants of the Brucella A polysaccharide, are the first synthetic analogues of this antigen. Their synthesis was necessitated by crystallographic studies of a Fab combining site obtained from a monoclonal antibody that binds the Brucella A antigen and synthetic pentasaccharide. Monosaccharide synthon 3 and disaccharide 7, S-ethyl glycoside derivatives of 4-azido-4,6-dideoxy-D-mannose, have been used successfully as key intermediates in a convergent strategy to synthesize a1,2-linked homo-oligosaccharides of 4,6-dideoxy-4-formamido-D-mannose. The disaccharide thioglycoside 7 was activated by methyl triflate in the presence of selectively protected mono-or trisaccharide alcohols 1, 6, or 10 to give al,2-linked tri-and pentasaccharides 8, 9, and 19. Despite the non-participating glycosyl substituent at position two of the thioglycoside, 1,2-trans glycosidic products appeared to be formed exclusively. Conversion of 3 to the glycosyl bromide 5 by bromine under mild conditions provided routes to both the disaccharide building block 7 and a tetrasaccharide 15 using conventional silver triflate promoted glycosylation reactions. Deprotection was accomplished by transesterification, hydrogen sulphide reduction of azido groups, followed by N-formylation and finally hydrogenolysis of benzyl ethers.Key words: Brucella A antigen, pentasaccharide synthesis, thioglycosides, oligosaccharide building units, 4,6-dideoxy-4-formamido-D-mannose, antibody combining sites.THOMAS PETERS et DAVID R. BUNDLE. Can. J. Chem. 67,491 (1989). Les glycosides de mCthyle 13, 18 et 22 qui reprtsentent des dkterminants antigtniques potentiels du polysaccharide de la Brucella A sont les premiers analogues de synthbse de cet antigkne. On a d13 rkaliser leur synthbse pour effectuer des analyses de structure par diffraction des rayons-X sur un Fab cristallin combinant le site de liaison de l'antigbne Brucella A et le pentasaccharide de synthbse. Le monosaccharide de synthbse 3 ainsi que le disaccharide 7, des dCrivts glycoside de S-Cthyle de l'azido-4 didksoxy-4,6 D-mannose, ont Ctt utilisCs avec succbs comme intermtdiaires clCs dans une strattgie convergente conduisant ?i la synthbse d'homo-oligosaccharides liCs en a1,2 du didCsoxy-4,6 formamido-4 D-mannose. On a activt le thioglycoside du disaccharide 7 par le triflate de mCthyle en prksence des mono-ou tri-saccharides alcools 1 , 6 ou 10, protCgCs d'une fagon stlective, et on a obtenu les tri-et penta-saccharides 8, 9 ou 19 lies par les positions a1,2. MalgrC la prCsence d'un substituant glycosyle non-participant en position deux du thioglycoside, il semble que les produits glycosidiques 1,2-trans se foment d'une fagon exclusive. La transformation du compost 3 en bromure de glycosyle, par l'action du brome dans des conditions douces, fournit des voies pouvant conduire, par des rCactions de glycosylation conventionnelles activtes par le triflate d'argent, soit au disaccharide 7 ou au tttrasacchar...

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An Alternative Method for the Selective Reduction of Unsaturated Nucleoside Azides to the Amines

Cited by 150 publications

References 0 publications

Glycosylation under Thermodynamic Control: Synthesis of the Di‐ and the Hexasaccharide Fragments of the O‐SP of Vibrio Cholerae O:1 Serotype Ogawa from Fully Functionalized Building Blocks

Glycosylation under Thermodynamic Control: Synthesis of the Di‐ and the Hexasaccharide Fragments of the O‐SP of Vibrio Cholerae O:1 Serotype Ogawa from Fully Functionalized Building Blocks

Synthesis of tri- and tetrasaccharide haptens related to the Asialo forms of the gangliosides G_M2 and G_M1

Synthetic antigenic determinants of the Brucella A polysaccharide: A disaccharide thioglycoside for block synthesis of pentasaccharide and lower homologues of α1,2-linked 4,6-dideoxy-4-formamido-α-D-mannose

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An Alternative Method for the Selective Reduction of Unsaturated Nucleoside Azides to the Amines

Cited by 150 publications

References 0 publications

Glycosylation under Thermodynamic Control: Synthesis of the Di‐ and the Hexasaccharide Fragments of the O‐SP of Vibrio Cholerae O:1 Serotype Ogawa from Fully Functionalized Building Blocks

Glycosylation under Thermodynamic Control: Synthesis of the Di‐ and the Hexasaccharide Fragments of the O‐SP of Vibrio Cholerae O:1 Serotype Ogawa from Fully Functionalized Building Blocks

Synthesis of tri- and tetrasaccharide haptens related to the Asialo forms of the gangliosides GM2 and GM1

Synthetic antigenic determinants of the Brucella A polysaccharide: A disaccharide thioglycoside for block synthesis of pentasaccharide and lower homologues of α1,2-linked 4,6-dideoxy-4-formamido-α-D-mannose

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Synthesis of tri- and tetrasaccharide haptens related to the Asialo forms of the gangliosides G_M2 and G_M1