851895-41-5

Upstream product

• 100-39-0 benzyl bromide 
• 596087-18-2 4-methylphenyl 2,3-di-O-benzyl-1-thio-β-D-glucopyranoside 
• 850416-39-6 p-methylphenyl 2,3-di-O-benzyl-4,6-O-(R)-benzylidene-1-thio-β-D-glucopyranoside 
• 617-86-7 triethylsilane 

Downstream Products

• 1200762-22-6 tolyl 2,3,6-tri-O-benzyl-4-O-levulinoyl-1-β-D-thioglucopyranoside 
• 1309834-90-9 C₆₈H₇₀O₁₀S 
• 260976-37-2 4-methylphenyl 4-azido-2,3,6-tri-O-benzyl-4-deoxy-1-thio-β-D-galactopyranoside 
• 1363157-73-6 p-methylphenyl 4-O-benzoyl-2,3,6-tri-O-benzyl-1-deoxy-1-thio-β-D-glucopyranoside 
• 1602921-57-2 6-chlorohexyl 4-O-(3,6-di-O-benzyl-2-deoxy-α-D-glucopyranosyl)-2,3,6-tri-O-benzyl-β-D-glucopyranoside 
• 1602921-54-9 6-chlorohexyl 4-O-(4-O-benzoyl-3,6-di-O-benzyl-2-deoxy-α-D-glucopyranosyl)-2,3,6-tri-O-benzyl-β-D-glucopyranoside 
• 1602921-16-3 p-tolyl 4-O-benzyl-3-O-(2-naphthylmethyl)-2,6-dideoxy-α-D-glucopyranosyl-(1→4)-2,3,6-tri-O-benzyl-1-thio-β-D-glucopyranoside 
• 1602921-17-4 p-tolyl 4-O-benzyl-3-O-(2-naphthylmethyl)-2,6-dideoxy-β-D-glucopyranosyl-(1→4)-2,3,6-tri-O-benzyl-1-thio-β-D-glucopyranoside 
• 1415590-75-8 methyl (2,3,6-tri-O-benzyl-4-O-picoloyl-α-D-glucopyranosyl)-(1→6)-2,3,4-tri-O-benzyl-α-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.

Phosphotungstic acid as a novel acidic catalyst for carbohydrate protection and glycosylation

This work demonstrates the utilization of phosphotungstic acid (PTA) as a novel acidic catalyst for carbohydrate reactions, such as per-O-acetylation, regioselective O-4,6 benzylidene acetal formation, regioselective O-4 ring-opening, and glycosylation. These reactions are basic and salient during the synthesis of carbohydrate-based bioactive oligomers. Phosphotungstic acid's high acidity and eco-friendly character make it a tempting alternative to corrosive homogeneous acids. The various homogenous acid catalysts were replaced by the phosphotungstic acid solely for different carbohydrate reactions. It can be widely used as a catalyst for organic reactions as it is thermally stable and easy to handle. In our work, the reactions are operated smoothly under ambient conditions; the temperature varies from 0 °C to room temperature. Good to excellent yields were obtained in all four kinds of reactions.

Combined inhibitor free-energy landscape and structural analysis reports on the mannosidase conformational coordinate

Mannosidases catalyze the hydrolysis of a diverse range of polysaccharides and glycoconjugates, and the various sequence-based mannosidase families have evolved ingenious strategies to overcome the stereoelectronic challenges of mannoside chemistry. Using a combination of computational chemistry, inhibitor design and synthesis, and X-ray crystallography of inhibitor/enzyme complexes, it is demonstrated that mannoimidazole-type inhibitors are energetically poised to report faithfully on mannosidase transition-state conformation, and provide direct evidence for the conformational itinerary used by diverse mannosidases, including β-mannanases from families GH26 and GH113. Isofagomine-type inhibitors are poor mimics of transition-state conformation, owing to the high energy barriers that must be crossed to attain mechanistically relevant conformations, however, these sugar-shaped heterocycles allow the acquisition of ternary complexes that span the active site, thus providing valuable insight into active-site residues involved in substrate recognition. Shipshape inhibitors: Quantum mechanical calculations of the free-energy landscape (see figure) of the glycosidase transition-state mimics isofagomine and mannoimidazole reveals that only the latter is energetically poised to report upon the mannosidase transition-state conformation. X-ray structures of β-mannanases from different families reveal they both adopt a boat conformation, thus allowing unification of the enzymatic conformational itinerary of a range of diverse α- and β-mannosidases.

Metal trifluoromethanesulfonate-catalyzed regioselective reductive ring opening of benzylidene acetals

A systematic study of various metal trifluoromethanesulfonates as efficient catalysts in the regioselective reductive ring opening of benzylidene acetals is described, including the effects of solvents, reducing agents, and temperature. These catalysts are found to be effective in cleaving the 4,6-O-acetal rings of hexopyranosides at either O4 or O6, respectively. When used in conjunction with a 1 M solution of BH3.THF in THF without extra addition of any solvent, it affects the ring fission at the O6 position to generate the corresponding primary alcohols, whereas O4-opening takes place in acetonitrile in the presence of dimethylethylsilane as the reductant leading to the secondary hydroxyl derivatives in high selectivity and yields. These methodologies can be applied to a wide range of substrates containing various functional groups.

Low-concentration 12-trans β-selective glycosylation strategy and its applications in oligosaccharide synthesis

This study develops an operationally easy, efficient, and general 1,2-trans β-selective glycosylation reaction that proceeds in the absence of a C2 acyl function. This process employs chemically stable thioglycosyl donors and low substrate concentrations to achieve excellent β-selectivities in glycosylation reactions. This method is widely applicable to a range of glycosyl substrates irrespective of their structures and hydroxyl-protecting functions. This low-concentration 1,2-trans β-selective glycosylation in carbohydrate chemistry removes the restriction of using highly reactive thioglycosides to construct 1,2-trans β-glycosidic bonds. This is beneficial to the design of new strategies for oligosaccharide synthesis, as illustrated in the preparation of the biologically relevant β-(1-6)-glucan trisaccharide, β-linked Gb3 and isoGb3 derivatives.

Regioselective benzylation of azido-containing monosaccharides

A regioselective benzylation or p-methoxybenzylation of diols in azido-containing monosaccharide derivatives was reported, and the reaction was performed under the conventional reaction conditions (NaH/BnBr in DMF). The hydroxyl functionality adjacent to the azido group was benzylated selectively in good yields. Georg Thieme Verlag Stuttgart.

Cu(OTf)2 as an efficient and dual-purpose catalyst in the regioselective reductive ring opening of benzylidene acetals

(Chemical Equation Presented) Reducing the choices. Cu(OTf)2 is an efficient and dual-purpose catalyst for the highly regioselective reductive ring openings of benzylidene acetals with either BH3 or Me 2EtSiH to give the corresponding primary and secondary alcohols (see scheme). Isotope studies have confirmed that both modes of ring cleavage proceed by an SN1 reaction pathway when borane or silane attack the acetal carbon center.