77667-86-8

Upstream product

• 89025-46-7 2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl fluoride 
• 106-54-7 p-Chlorothiophenol 
• 6564-72-3 2,3,4,6-tetra-O-benzyl-D-glucopyranose 

Relevant academic research and scientific papers

Anodic Reactivity of Alkyl S-Glucosides

A voltammetric study of a series of alkyl and aryl S-glucosides unveiled the reactivity patterns of alkyl S-glucosides toward anodic oxidation and found noteworthy differences with the trends followed by aryl derivatives. The oxidation potential of alkyl S-glucosides, estimated herein from square-wave voltammetry peak potentials (Ep), depends on the steric properties of the aglycone. Glucosides substituted with bulky groups exhibit Ep values at voltages more positive than the values of those carrying small aglycones. This relationship, observed in all analyzed alkyl series, is evidenced by good linear correlations between Ep and Taft's steric parameters (ES) of the respective alkyl substituents. Moreover, the role of the aglycone's steric properties as a primary reactivity modulator is backed by poor correlations between Ep and the radical stabilization energies (RSEs) of the aglycone-derived thiyl radicals (RS?). In contrast, aryl glucosides' Ep values exhibit excellent correlations with the aryl substituents' Hammett parameters (σ+) and the ArS?RSEs, evidencing the inherent stability of the reactive radical intermediate as the primary factor controlling aryl glucoside's electrochemical reactivity. The reactivity differences between alkyl and aryl S-glucosides also extend to the protective group's effect on Ep. Alkyl S-glucosides' reactivity proved to be more sensitive to protective group exchange.

Metal-free glycosylation with glycosyl fluorides in liquid SO2

Liquid SO2 is a polar solvent that dissolves both covalent and ionic compounds. Sulfur dioxide possesses also Lewis acid properties, including the ability to covalently bind Lewis basic fluoride ions in a relatively stable fluorosulfite anion (FSO2?). Herein we report the application of liquid SO2 as a promoting solvent for glycosylation with glycosyl fluorides without any external additive. By using various temperature regimes, the method is applied for both armed and disarmed glucose and mannose-derived glycosyl fluorides in moderate to excellent yields. A series of pivaloyl-protected O- and S-mannosides, as well as one example of a C-mannoside, are synthesized to demonstrate the scope of the glycosyl acceptors. The formation of the fluorosulfite species during the glycosylation with glycosyl fluorides in liquid SO2 is proved by 19F NMR spectroscopy. A sulfur dioxide-assisted glycosylation mechanism that proceeds via solvent separated ion pairs is proposed, whereas the observed α,β-selectivity is substrate-controlled and depends on the thermodynamic equilibrium.

SYNTHESIS OF PHENYL D-GLUCOPYRANOSIDES; NUCLEOPHILIC SUBSTITUTION OF O-(2,3,4,6-TETRA-O-BENZYL-D-GLUCOPYRANOSYL)-PSEUDOUREAS BY PHENOLS

A series of nucleophilic substitution-reactions of O-(2,3,4,6-tetra-O-benzyl-D-glucopyranosil)pseudoureas by phenols was investigated as a novel procedure for the synthesis of phenyl D-glucopyranoside derivatives; these reactions were found to give the corresponding phenyl 2,3,4,6-tetra-O-benzyl-D-glucopyranosides in excellent yields.Reaction mechanisms were discussed on the basis of the results obtained.