440345-54-0

Upstream product

• 929040-55-1 p-tolyl 2-azido-4,6-O-benzylidene-2-deoxy-1-thio-α-D-glucopyranoside 
• 67-56-1 methanol 
• 502692-41-3 p-tolyl 2-azido-3-O-benzyl-4,6-O-benzylidene-2-deoxy-1-thio-β-D-glucopyranoside 
• 929040-77-7 4-methylphenyl 3,4,6-tri-O-acetyl-2-azido-2-deoxy-1-thio-α,β-D-glucopyranoside 
• 100-52-7 benzaldehyde 
• 1235137-50-4 p-tolyl 2-deoxy-2-azido-3-O-benzyl-4,6-O-benzylidene-1-thio-α-D-glucopyranoside 
• 100-39-0 benzyl bromide 
• 274260-02-5 methyl 2-azido-4,6-O-benzylidene-2-deoxy-β-D-glucopyranoside 

Downstream Products

• 440345-48-2 Acetic acid (2S,3R,4S,5S,6R)-2-[(2R,3S,4R,5R,6R)-5-azido-4-benzyloxy-2-(tert-butyl-dimethyl-silanyloxymethyl)-6-methoxy-tetrahydro-pyran-3-yloxy]-4,5-bis-benzyloxy-6-benzyloxymethyl-tetrahydro-pyran-3-yl ester 
• 440345-52-8 methyl 2-acetamido-2-deoxy-3-O-benzyl-4-O-(3,4,6-tri-O-benzyl-β-D-galactopyranosyl)-2',6-di-O-(methane-1,2-diyl)-β-D-glucopyranoside 
• 440345-49-3 methyl 2-azido-2-deoxy-3-O-benzyl-4-O-(2-O-acetyl-3,4,6-tri-O-benzyl-β-D-galactopyranosyl)-β-D-glucopyranoside 
• 440345-50-6 methyl 2-azido-2-deoxy-3-O-benzyl-4-O-(3,4,6-tri-O-benzyl-β-D-galactopyranosyl)-β-D-glucopyranoside 
• 440345-51-7 methyl 2-azido-2-deoxy-3-O-benzyl-4-O-(3,4,6-tri-O-benzyl-β-D-galactopyranosyl)-2',6-di-O-(methane-1,2-diyl)-β-D-glucopyranoside 
• 440345-47-1 methyl 2-azido-3-O-benzyl-2-deoxy-6-O-tert-butyldimethylsilyl-2-deoxy-β-D-glucopyranoside 
• 440345-53-9 methyl 2-azido-3-O-benzyl-2-deoxy-β-D-glucopyranoside 

Relevant academic research and scientific papers

Automated Quantification of Hydroxyl Reactivities: Prediction of Glycosylation Reactions

The stereoselectivity and yield in glycosylation reactions are paramount but unpredictable. We have developed a database of acceptor nucleophilic constants (Aka) to quantify the nucleophilicity of hydroxyl groups in glycosylation influenced by the steric, electronic and structural effects, providing a connection between experiments and computer algorithms. The subtle reactivity differences among the hydroxyl groups on various carbohydrate molecules can be defined by Aka, which is easily accessible by a simple and convenient automation system to assure high reproducibility and accuracy. A diverse range of glycosylation donors and acceptors with well-defined reactivity and promoters were organized and processed by the designed software program “GlycoComputer” for prediction of glycosylation reactions without involving sophisticated computational processing. The importance of Aka was further verified by random forest algorithm, and the applicability was tested by the synthesis of a Lewis A skeleton to show that the stereoselectivity and yield can be accurately estimated.

Mapping mechanisms in glycosylation reactions with donor reactivity: Avoiding generation of side products

The glycosylation reaction, which is key for the studies on glycoscience, is challenging due to its complexity and intrinsic side reactions. Thioglycoside is one of the most widely used glycosyl donors in the synthesis of complex oligosaccharides. However, one of the challenges is its side reactions, which lower its yield and limits its efficiency, thereby requiring considerable effort in the optimization process. Herein, we reported a multifaceted experimental approach that reveals the behaviors of side reactions, such as the intermolecular thioaglycon transformation and N-glycosyl succinimides, via the glycosyl intermediate. Our mechanistic proposal was supported by low temperature NMR studies that can further be mapped by utilizing relative reactivity values. Accordingly, we also presented our findings to suppress the generation of side products in solving this particular problem for achieving high-yield glycosylation reactions.

Establishment of Guidelines for the Control of Glycosylation Reactions and Intermediates by Quantitative Assessment of Reactivity

Stereocontrolled chemical glycosylation remains a major challenge despite vast efforts reported over many decades and so far still mainly relies on trial and error. Now it is shown that the relative reactivity value (RRV) of thioglycosides is an indicator for revealing stereoselectivities according to four types of acceptors. Mechanistic studies show that the reaction is dominated by two distinct intermediates: glycosyl triflates and glycosyl halides from N-halosuccinimide (NXS)/TfOH. The formation of glycosyl halide is highly correlated with the production of α-glycoside. These findings enable glycosylation reactions to be foreseen by using RRVs as an α/β-selectivity indicator and guidelines and rules to be developed for stereocontrolled glycosylation.

α-(2,6)-sialyltransferase-catalyzed sialylations of conformationally constrained oligosaccharides

It is demonstrated that conformationally restricted oligosaccharides can act as acceptors for glycosyltransferases. Correlation of the conformational properties of N-acetyl lactosamine (Galβ/(1-4)GlcNAc, LacNAc) and several preorganized derivatives with t