Über benzylierte Derivate des Lävoglucosans und der Glucose

Zemplén, Geža; Csűrös, Z.; Angyal, Stefan

doi:10.1002/cber.19370700903

Cited by 77 publications

(23 citation statements)

References 3 publications

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“…Acetolysis followed by conversion to the glycosyl chloride 4 provides a rapid route via glycosylation of 8-methoxycarbonyloctanol to the desired intermediate a-glycosides 5 and 7. The yields achieved compare favourably with previous work (19).…”

Section: Discussionsupporting

confidence: 84%

“…A suitable derivative, 2,4-di-0-benzyl-l,6-anhydro-P-D-glucopyranose, has been reported in the literature (19)(20)(21). Benzylation of 1,6-anhydro-P-Dglucopyranose (1) with benzyl bromide and barium oxide in DMF gave 2 in 95% yield compared with the previously reported yield of 21%.…”

Section: Resultsmentioning

confidence: 85%

“…These difficulties may be circumvented for some purposes by the use of 1,6-anhydro-P-Dglucopyranose (1) (20). For the purpose of generating 3,6-disubstituted glucopyranose residues, benzylation of 1 to give the 2,4-di-0-benzyl-glucopyranose 2 offers the most direct route (19)(20)(21), although the published yield is low (19). By comparison, an alternate route to a 2,4-di-0-benzyl-Dglucopyranoside was recently reported (24).…”

Section: Discussionmentioning

confidence: 99%

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Synthesis of the colitose determinant of Escherichiacoli O111 and 3,6-di-O-(α-D-galactopyranosyl)-α-D-glucopyranoside

Iversen¹,

Bundle²

1982

Can. J. Chem.

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TOMMY IVERSEN and DAVID R. BUNDLE. Can. J. Chem. 60, 299 (1982). The syntheses of two branched trisaccharides, which constitute important elements of enterobacterial lipopolysaccharides are described. The common structural feature of each trisaccharide is a-D-glucopyranoside, upon which branching occurs at the 0 -3 and 0 -6 positions. Selective blocking of this hexoside at 0 -2 and 0-4 by persistent blocking groups was accomplished by benzylation of 1 ,6-anhydro-P-D-glucopyranoside (1). Acetolysis of the product 2 afforded a mixture of anomeric triacetates 3 from which the corresponding 3,6-di-0-acetyI-2,4-O-benzyl-a-~-glucopyranosyl chloride (4) was prepared. The a and P 8-methoxycarbonyloctyl glycosides 5 and 6 were obtained in the ratio -2:1, when 4 was reacted with 8-methoxycarbonyloctanol. Transesterification of the a-glycoside 5 gave the aglyconic intermediate 7 from which each trisaccharide could be obtained in a one step reaction. Thus glycosylation of 7 with tetra-0-benzyl-a-D-galactopyranosyl chloride (8) or 2,4-di-0-benzyl-3,6-dideoxy-a-Lxylo-hexopyranosyl chloride (10) gave the trisaccharides 11 and 13. In both cases removal of blocking groups was achieved in a single hydrogenolysis step. Trisaccharide 12 represents a trisaccharide sequence present in the core saccharide of Salmonella lipopolysaccharides, while the colitose containing trisaccharide 14 is an essential element of the E. coli 011 1 0-antigen.TOMMY IVERSEN et DAVID R. BUNDLE. Can. J . Chem. 60, 299 (1982).On decrit la synthese de deux trisaccharides ramifies qui constituent des elements importants des lipopolysaccharides enterobacteriens. La caracteristique structurale commune a chaque trisaccharide est I'a-D-glucopyrannoside, sur lequel s'effectue les ramification en positions 0-3 et 0-6. On a p11 proteger selectivement cet hexoside en positions 0 -2 et 0 -4 a I'aide de groupes protecteurs tres stables en benzylant I'anhydro-1,6 P-D-glucopyrannose (I). L'acelotyse du compose 2 conduit a un melange de triacetates 3 anomeres a partir duquel on a prepare le chlorure de di-0-acetyl-3,6 0-benzyl-2,4 a-D-glucopyrannosyle (4). On a obtenu les a -et P-glycosides de methoxycarbonyl-8 octyle, 5 et 6, dans un rapport de 2: 1 environ en faisant reagir le compose 4 avec le methoxycarbonyl-8 octanol. La transesterification de l'a-glycoside conduit al'intermediaire aglyconique 7 a partir duquel on peut obtenir chaque trisaccharide en une seule etape. Ainsi la glycosilation du compose 7 par le chlorure de tetra-0-benzyl a-D-galactopyrannosyle (8) ou par le chlorure de di-0-benzyl-2,4 dideoxy-3,6 a-L-xylohexopyrannosyle (10) donne les trisaccharides 11 et 13. Dans les deux cas, I'hydrolyse permet d'effectuer la deprotection en une seule etape. Le trisaccharide 12 represente une suite de trisaccharides presents dans le noyau saccharique des lipopolysaccharides du type Salmonella, tandis que le trisaccharide 14 contenant la colitose est un element essentiel de I'antigene 0 de I'E. Coli 0 1 11.[Traduit par le journal] Introduction Although antigenic determ...

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Section: Discussionsupporting

confidence: 84%

Section: Resultsmentioning

confidence: 85%

Section: Discussionmentioning

confidence: 99%

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Synthesis of the colitose determinant of Escherichiacoli O111 and 3,6-di-O-(α-D-galactopyranosyl)-α-D-glucopyranoside

Iversen¹,

Bundle²

1982

Can. J. Chem.

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“…1). The problems then were not very different from those we have to tackle now but the methods available for solving them were very primitive compared with to-day's.…”

Section: Introductionmentioning

confidence: 99%

Topics in carbohydrate stereochemistry

Angyal¹

1987

Pure and Applied Chemistry

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-In its crystal form, D-glycero--L-allo-heptitol is in the 3G form which has a 1,3-parallel interaction btween an xygen and a carbon atom. In solution, the heptitol and its acetate also assume this conformation. Such an interaction, not previously reported for an alditol, has also been found to occur in several other straight-chain sugar derivatives.Characteristic differences were found between the values of carbohydrates on ion-exchange t.l.c. plates in the calcium and in the lanthanum form. Alditols which have a yj sequence of three hydroxyl groups complex better with La(II]I) ions; methyl glycosides complex better with Ca(II) ions.In the Koch-Stuart method of replacing carbon-bound hydrogen atoms with deuterium over Raney nickel, some hydrogen atoms exchange slower than do others, depending on their environment and steric hindrance. Use has been made of these differences in order to prepare selectively deuterium-labelled sugars.

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“…The early work on benzylated carbohydrates utilized the hydriodic acid fission of ethers, as used for methoxyl estimation, for determining benzyl groups (8). However, that method involves isolation of the lachrymatory benzyl iodide and is rendered invalid by the presence of a methoxyl group in the compound being analyzed.…”

mentioning

confidence: 99%

PREPARATION, THIN LAYER CHROMATOGRAPHY, AND ULTRAVIOLET SPECTRA OF SOME O-BENZYL DERIVATIVES OF D-GLUCOSE

Tate¹,

Bishop²

1963

Can. J. Chem.

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A slew method for benzylation of carbohydrates has been developed which facilitated complete substitution of hydroxyl groups in one of the compou~lds prepared. Thin layer chronlatography provides a good criterion of purity and is also a preparative method for separation of identifiable amounts of 0-benzyl derivatives of carbohydrates. The number of benzyl groups in a compound can be determined by ultraviolet absorption spectroscopy. The following cornpoutlds were prepared, some of which have not been reported previously:benz>-1-2,3,4,6 -tetra-0-benzyl-a-D -glucoside; benzyl 2,3,4,6-t e t r a -0 -benzyl-p-D-glucoside; methyl 2,3,4,6-tetra-0-benzyl-WD-glucoside; 2,3,4,6-tetra-0-benzyl-a-D-glucose; 1-0-(p-nitrobenzoy1)-2,3,4,6-tetra-0-benzyl-m-D-glucose; octa-0-benzyl sucrose; 3,5-di-0-benzyl-1,2-0-c~~clohexylidene-a-D-xylose.

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Über benzylierte Derivate des Lävoglucosans und der Glucose

Cited by 77 publications

References 3 publications

Synthesis of the colitose determinant of Escherichiacoli O111 and 3,6-di-O-(α-D-galactopyranosyl)-α-D-glucopyranoside

Synthesis of the colitose determinant of Escherichiacoli O111 and 3,6-di-O-(α-D-galactopyranosyl)-α-D-glucopyranoside

Topics in carbohydrate stereochemistry

PREPARATION, THIN LAYER CHROMATOGRAPHY, AND ULTRAVIOLET SPECTRA OF SOME O-BENZYL DERIVATIVES OF D-GLUCOSE

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