885375-13-3

Upstream product

• 76375-66-1 methyl 2-O-benzyl-4,6-O-benzylidene-α-D-glucopyranoside 
• 1423496-75-6 p-methylphenyl 3,4,6-tri-O-benzyl-2-deoxy-1-thio-α-D-glucopyranoside 
• 3162-96-7 4,6-O-benzylidene-1-O-methyl-α-D-glucopyranoside 
• 100-39-0 benzyl bromide 
• 1360560-44-6 p-methylphenyl 3,4,6-tri-O-benzyl-2-deoxy-1-thio-β-D-glucopyranoside 
• 119070-22-3 phenyl 2-deoxy-3,4,6-tris-O-(phenylmethyl)-1-thio-D-arabino-hexopyranoside 
• 1588522-56-8 C₂₁H₂₃O₆^(1-)*K⁽¹⁺⁾ 
• 160549-11-1 3,4,6-tri-O-benzyl-2-deoxy-D-glucopyranose 
• 91780-43-7 phenyl 3,4,6-tri-O-benzyl-2-deoxy-1-thio-β-D-arabino-hexopyranoside 

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.

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.

Glycosylation Reactions Using Phenyl(trifluoroethyl)iodonium Salts

Provided are methods for the preparation of glycosylation products, including those represented by formula I: [in-line-formulae]Sugar-O—R′??I[/in-line-formulae]comprising the step of combining R′—OH, a glycosyl sulfide glycosyl donor (“thioglycoside donor

Reagent-Controlled Stereoselective Glycosylation

Provided are methods for the efficient stereoselective formation of glycosidic bonds, without recourse to prosthetic or directing groups.

A reagent-controlled SN2-glycosylation for the direct synthesis of β-linked 2-deoxy-sugars

The efficient and stereoselective construction of glycosidic linkages remains one of the most formidable challenges in organic chemistry. This is especially true in cases such as β-linked deoxy-sugars, where the outcome of the reaction cannot be controlled using the stereochemical information intrinsic to the glycosyl donor. Here we show that p-toluenesulfonic anhydride activates 2-deoxy-sugar hemiacetals in situ as electrophilic species, which react stereoselectively with nucleophilic acceptors to produce β-anomers exclusively. NMR studies confirm that, under these conditions, the hemiacetal is quantitatively converted into an α-glycosyl tosylate, which is presumably the reactive species in the reaction. This approach demonstrates that use of promoters that activate hemiacetals as well-defined intermediates can be used to permit stereoselective glycosylation through an SN2-pathway.

An Air- and water-stable iodonium salt promoter for facile thioglycoside activation

The air- and water-stable iodonium salt phenyl(trifluoroethyl)iodonium triflimide is shown to activate thioglycosides for glycosylation at room temperature. Both armed and disarmed thioglycosides rapidly undergo glycosylation in 68-97% yield. The reaction