4159-55-1

Upstream product

• 69895-14-3 methyl (2,3,4,6-tetra-O-acetyl-D-glucopyranosyl)-β-(1→6)-2,3,4-tri-O-benzoyl-α-D-glucopyranoside 
• 34234-44-1 methyl 2,3,4-tri-O-benzoylglucopyranoside 
• 14218-11-2 2,3,4,6-tetra-O-benzoylglucosyl bromide 
• 76679-49-7 methyl 2,3,4-tri-O-benzyl-β-D-glucopyranosyl-(1->6)-2,3,4-tri-O-benzyl-α-D-glucopyranoside 
• 3162-96-7 methyl 4,6-O-benzylidene-α-D-glucopyranoside 
• 572-09-8 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide 
• 104291-14-7 methyl 2,3,4-tri-O-pentanoyl-α-D-glucopyranoside 
• 74808-10-9 O-(2,3,4,6-Tetra-O-acetyl-α-D-glucopyranosyl)trichloroacetimidate 
• 205755-06-2 Succinic acid mono-{(2R,3R,4S,5R,6S)-4,5-diacetoxy-2-[bis-(4-methoxy-phenyl)-phenyl-methoxymethyl]-6-methoxy-tetrahydro-pyran-3-yl} ester 
• 149707-75-5 2,3,4,6-tetra-O-benzoyl-D-glucopyranosyl trichloroacetimidate 
• 241470-93-9 methyl 4,6'-O-(1,3-xylylene)-(2,3,4-tri-O-benzyl-β-D-glucopyranosyl)-(1'->6)-2,3-di-O-benzyl-α-D-glucopyranoside 
• 873093-23-3 methyl 2,3,4-tri-O-benzyl-6-O-(3,4,6-tri-O-benzyl-2-O-picolinyl-β-D-glucopyranosyl)-α-D-glucopyranoside 
• 4141-45-1 methyl-4,6-O-benzylidene-2,3-diacetyl-α-D-glucopyranoside 
• 477949-33-0 Acetic acid (2S,3R,4S,5R,6R)-3-acetoxy-6-[bis-(4-methoxy-phenyl)-phenyl-methoxymethyl]-5-hydroxy-2-methoxy-tetrahydro-pyran-4-yl ester 

Relevant academic research and scientific papers

Completely β-selective glycosylation using 3,6- O-(o-xylylene)-bridged axial-rich glucosyl fluoride

A completely β-selective glycosylation that does not rely on neighboring group participation is described. The novelty of this work is the design of the glycosyl donor locked into the axial-rich form by the o-xylylene bridge between the 3-O and 6-O of d-glucopyranose. The synthesized 2,4-di-O-benzyl-3,6-O-(o-xylyene)glucopyranosyl fluoride could efficiently react with various alcohols in a SnCl2-AgB(C6F 5)4 catalytic system. The mechanism composed of the glycosylation and isomerization cycles was revealed through comparative experiments using acidic and basic molecular sieves. The achieved perfect stereocontrol is attributed to the synergy of the axial-rich conformation and convergent isomerization caused by HB(C6F5)4 generated in situ.

A fluorous-assisted synthesis of oligosaccharides using a phenyl ether linker as a safety-catch linker

We report on the fluorous-assisted synthesis of oligosaccharides using a phenyl ether linker. The phenyl ether linker is stable under both acidic and basic conditions but can be cleaved under mildly acidic conditions after reduction to a vinyl ether. The utility of the method was demonstrated by the synthesis of a trisaccharide. A protected trisaccharide with a light-fluorous tag was directly prepared by one-pot glycosylation using three building blocks that contained a building block with a light-fluorous tag though a phenyl ether. A Birch reduction of the trisaccharide provided a fully deprotected trisaccharide with the fluorous tag attached through a vinyl ether, which was easily purified by solid-phase extraction. The tag was cleaved from the sugar portion by treatment with 3% TFA in MeOH.

How the arming participating moieties can broaden the scope of chemoselective oligosaccharide synthesis by allowing the inverse armed-disarmed approach

(Chemical Equation Presented) A new method for stereocontrolled glycosylation and chemoselective oligosaccharide synthesis has been developed. It has been determined that complete 1,2-trans selectivity can be achieved with the use of a 2-O-picolyl moiety,

Development of an arming participating group for stereoselective glycosylation and chemoselective oligosaccharide synthesis

(Chemical Equation Presented) Armed and dangerous: A new armed-disarmed glycosylation strategy (see picture) allows chemoselective introduction of a 1,2-trans glycosidic linkage prior to other linkages through the use of a 2-O-picolyl moiety. This neighbo

Removal of benzyl protecting groups from controlled pore glass linked sugars

Removal of benzyl protecting groups from controlled pore glass bound monosaccharides can be performed with the NaBrO3/Na2S2O4 system in ethyl acetate/water.

Efficient Intramolecular Glycosylation Supported by a Rigid Spacer

The m-xylylene moiety was employed as rigid spacer in intramolecular glycoside bond formation. Fifteen-membered macrocycle formation starting from 6-O-linked donor and 6- and 4-O-linked acceptor (5a,b, 6b) led exclusively to β(1-4)- and β(1-6)-linked compounds 7β and 8β, respectively, which gave cellobioside and gentiobioside derivatives. The glycosylation yields could be improved by 14-membered macrocycle formation. In the four cases studied, the donor was 6-O-linked to the spacer. For the acceptor linkage to the spacer and the accepting hydroxy group, relative D-/L-threo- and D-/L-erythro-arrangements were chosen. Standard glycosylation conditions led in three cases (13, 14, 23) only to β-linkage in high yield (16β, 17β, 25β). For the transformation of 24, having a D-erythro-arrangement in the acceptor moiety, the α-anomer 26α was preferentially obtained. Limitation of the conformational space of the donor and the acceptor as in 31, which is stereochemically identical with 24, led to the corresponding α-glycoside 32α in 87% yield. Synthesis of a pseudo mirror image of 23 [having 6-(D)/3-(D-threo)-arrangement], namely 35, having 3(L)/6-(L-threo)-arrangement of the donor and acceptor moieties, expectedly gave only α-glycoside 36α in very high yield. Thus, the efficiency and versatility of this conceptual approach to intramolecular glycoside bond formation is exhibited.

Use of controlled pore glass in solid phase oligosaccharide synthesis. Application to the semiautomated synthesis of a glyconucleotide conjugate

Three polymetric supports (polystyrene. Tentagel and controlled pore glass) have been tested for solid phase synthesis of oligosaccharides based on the trichlorocctimidate methodology. Controlled pore glass has been found to yield satisfactory results wit

Nuclear Magnetic Resonance Studies of 1,6-Linked Disaccharides

The signals in the (13)C n.m.r. spectra of all anomeric forms of the methyl glycosides of D-Glcp-(1-->6)-D-Glcp and D-Glcp-(1-->6)-D-Galp in water have been assigned.The chemical-shift differences obtained by comparison with relevant monosaccharide derivatives were used to calculate (13)C n.m.r. spectra of oligo- and poly-saccharides containing 1,6-linkages.Good agreement between calculated and experimental spectra were obtained for raffinose, stachyose, dextran, and pustulan.The importance of comparing spectra determined at the same temperature is emphasized.Temperature shifts may, in favourable cases, be used for assignment of signals.

PREPARATION OF α AND Β ANOMERS OF VARIOUS ISOMERIC METHYL O-D-GALACTOPYRANOSYL-D-GALACTOPYRANOSIDES. STANDARDS FOR INTERPRETATION OF 13C-N.M.R. SPECTRA OF D-GALACTOPYRANANS

The four isomer of methyl O-β-D-galactopyranosyl-β-D-galactopyranoside were prepared by condensation of 2,3,4,6-tetra-O-acetyl-α-galactopyranosyl bromide with appropriate, partially O-substitued derivatives of methyl β-D-galactopyranoside.Reaction of 3,4,6-tri-O-acetyl-1,2-O-(1-ethoxyethylidene)-α-D-galactopyranose with the same acceptors, in the presence of mercuric bromide, led to the formation of α and β linkages.Thus, it was possible to assign 13C-n.m.r. resonances of α and β anomers of methyl O-D-galactopyranosyl-β-D-galactopyranosides.In terms of application of these shift values and those of related D-galactobioses to the structual analysis of D-galactopyranans by shift comparisons, some generalizations can be made.For β-D-galactopyranans, the resonances glycosyloxylated carbon atoms of methyl O-β-D-galactopyranosyl-β-D-galactopyranosides are sensitive to structure and appear to have typical values, whereas limited variation was observed with shift of C-1' signals.On the other hand, for assigning structures to D-galactopyranans containing α linkages, the C-1' shifts (at higher field) of methyl O-α-D-galactopyranosyl-β-D-galactopyranosidesc are sensitive to linkage position, whereas those of glycosyloxylated carbon atoms vary only a little.