115220-82-1

Upstream product

• 100-44-7 benzyl chloride 
• 496-62-8 D-xylal 
• 3152-43-0 3,4-di-O-acetyl-D-xylal 
• 3068-31-3 1-bromo-2,3,4-tri-O-acetyl-α-D-xylopyranose 
• 100-39-0 benzyl bromide 
• 131771-66-9 phenyl 2,3,4-tri-O-benzyl-1-thio-β-D-xylopyranoside 
• 116661-76-8 1,5-anhydro-3,4-di-O-benzyl-2-deoxy-D-erythro-pent-1-enitol 
• 108-24-7 acetic anhydride 

Downstream Products

• 195058-19-6 2,3-di-O-benzyl-4-O-formyl-D-threose 
• 911028-18-7 (2R,3R)-2,3-bis(benzyloxy)pentane-1,5-diol 
• 615564-35-7 (2R,3R,4R,5R)-4,5-Bis-benzyloxy-2-((2R,3R,4S,5R,6R)-3,4,5-tris-benzyloxy-6-benzyloxymethyl-tetrahydro-pyran-2-yloxy)-tetrahydro-pyran-3-ol 
• 1134932-11-8 methyl 3,4-di-O-benzyl-α-D-lyxopyranoside 
• 80973-55-3 Methyl 3,4-di-O-benzyl-β-D-xylopyranoside 
• 1134932-47-0 ethyl 3,4-di-O-benzyl-β-D-xylopyranoside 
• 1403609-02-8 (R)-3-(benzyloxy)-2H-pyran-4(3H)-one 

Relevant academic research and scientific papers

Electrochemical Trifluoromethylation of Glycals

Carbohydrates play essential roles in various physiological and pathological processes. Trifluoromethylated compounds have wide applications in the field of medicinal chemistry. Herein, we report a practical and efficient trifluoromethylation of glycals b

Palladium catalyzed stereocontrolled synthesis of C-aryl glycosides using glycals and arenediazonium salts at room temperature

A stereocontrolled synthesis of aryl-C-glycosides was achieved using glycals and aryldiazonium salts in the presence of palladium acetate. A wide range of glycals including d-glucal, d-galactal, l-rhamnal, d-xylal and d-ribal underwent C-arylation at the anomeric carbon in the presence of different aryldiazonium tetrafluoroborates and gave synthetically useful 2,3-deoxy-3-keto-α-aryl-C-glycosides in good to excellent yields. Broad substrate scope, simple operation and room temperature reactions make this protocol very attractive in organic synthesis.

Divergent synthesis of 2-C-branched pyranosides and oxepines from 1,2-gem-dibromocyclopropyl carbohydrates

The ring opening of 1,2-(gem-dibromo)cyclopropyl carbohydrates by two different modes leads to either 2-C-(bromomethylene)pyranosides (using base) or 2-bromooxepines (using silver salts), as shown previously by us for a D-glucal-derived cyclopropane. The base-promoted ring opening is extended to encompass additional alcohol, thiol and amine nucleophiles, and diastereoisomeric cyclopropane precursors. Cross-coupling of the 2-C-(bromomethylene)pyranosides leads to extended 2-C-branched pyranosides. Silver-promoted ring expansion of the cyclopropyl carbohydrates in the presence of various alcohols is described. Cross-coupling of the resulting benzyl 2-bromooxepines affords 2-C-substituted oxepines.

Stereoelectronic factors in the stereoselective epoxidation of glycals and 4-deoxypentenosides

Glycals and 4-deoxypentenosides (4-DPs), unsaturated pyranosides with similar structures and reactivity profiles, can exhibit a high degree of stereoselectivity upon epoxidation with dimethyldioxirane (DMDO). In most cases, the glycals and their corresponding 4-DP isosteres share the same facioselectivity, implying that the pyran substituents are largely responsible for the stereodirecting effect. Fully substituted dihydropyrans are subject to a "majority rule", in which the epoxidation is directed toward the face opposite to two of the three groups. Removing one of the substituents has a variable effect on the epoxidation outcome, depending on its position and also on the relative stereochemistry of the remaining two groups. Overall, we observe that the greatest loss in facioselectivity for glycals and 4-DPs is caused by removal of the C3 oxygen, followed by the C5/anomeric substituent, and least of all by the C4/C2 oxygen. DFT calculations based on polarized-π frontier molecular orbital (PPFMO) theory support a stereoelectronic role for the oxygen substituents in 4-DP facioselectivity, but less clearly so in the case of glycals. We conclude that the anomeric oxygen in 4-DPs contributes toward a stereoelectronic bias in facioselectivity whereas the C5 alkoxymethyl in glycals imparts a steric bias, which at times can compete with the stereodirecting effects from the other oxygen substituents.

Tandem epoxidation-alcoholysis or epoxidation-hydrolysis of glycals catalyzed by titanium(IV) isopropoxide or Venturello's phosphotungstate complex

Venturello's phosphotungstate complex and titanium(IV) isopropoxide [Ti(O-i-Pr)4] were successfully used as catalysts for the epoxidation-alcoholysis of glycals using hydrogen peroxide [H2O 2]. Reaction substrates included a range of variously protected glycals and different alcohols were used as solvents. Ti(O-i-Pr)4 was only effective in methanol as solvent, but gave methyl glycosides in high yields and high selectivities. The Venturello complex proved to be a very versatile and efficient catalyst. Apart from epoxidation-alcoholysis in alcoholic solvents it also showed activity in biphasic conditions to allow for glycosylation of long-chain alcohols and was very effective in the stereoselective dihydroxylation of benzylated glucal.

ortho-Thioquinones, new acceptors for the stereoselective synthesis of aryl 2-deoxy-O-glycosides

α-Hydroxynaphthylthiophthalimide (1) is a suitable precursor of the reactive ortho-thioquinone 2, which can be generated in situ and trapped by glycals. The reaction is an inverse electron-demand [4+2] cycloaddition that occurs in a totally regioselective

Synthesis of Cyclic Phosphonate Analogs of Ribose and Arabinose

The cyclic phosphonates of ribose and arabinose (phostones) 10-13 were synthesized by a Lewis acid-catalyzed addition of trimethyl phosphite to the partially protected D-threose 7 to give the acyclic phosphonates 8 and 9. This Abramov reaction was moderately stereoselective (3:1). A base-catalyzed cyclization of the mixture of 8 and 9 gave the four isomeric phosphonates 10-13. Two of the isomers, 10 and 11, could be crystallized from the reaction mixture. The stereochemistries of 11 and 16, the tribenzyl ether from 10, were proven by X-ray crystallography, and the stereochemistries of the other isomers and derivatives were determined by 31P NMR chemical shift data. The X-ray data and solution NMR data indicate that these phostones and their derivatives exist exclusively in a chair conformation.

THE ALKYLATION AND ACYLATION OF GLYCALS VIA AN INITIALIZING ELECTROCHEMICAL STEP

The method of electrochemically induced formation of ether and ester derivatives of saturated mono- and disaccharides was applied to 1,2-unsaturated monosaccharides (D-glycals).The influence of the supporting electrolyte on the product distribution was investigated by variation of the cation.To provide data for comparison, alkylation was also carried out chemically in the presence of different bases, e.g.LiH and NaH.

GLYCALS IN STEREOSPECIFIC SYNTHESIS. II. DI-O-BENZYL-L-ARABINAL AND DI-O-BENZOYL-L-ARABINAL IN THE SYNTHESIS OF SATURATED AND UNSATURATED TERMINAL EPOXIDES

The acid opening of di-O-benzyl-L-arabinal and di-O-benzoyl-L-arabinal, catalyzed by mercuric sulfate, is the key stage in the synthesis of chiral dihydroxy compounds with selectively protected hydroxy functions.They were used for the production of saturated and unsaturated terminal epoxides, which are of potential interest as chiral units in the convergent synthesis of biologically active compounds.

SYNTHESE DE PHOSPHORAMIDATES DE 2-DESOXY-2-IODOGLYCOSYLES

Addition of iodoazide to acetylated, benzylated, and methoxymethylated glycals yielded 2-deoxy-2-iodoglycosyl azides with 1,2-trans configuration.Stereoselectivity of the reaction favored the manno and talo configurations starting from D-glucal and D-galactal, respectively.With D-xylal derivatives, the stereoselectivity depended on the nature of the substituents.The Staudinger reaction of 2-deoxy-2-iodoglycosyl azides with trimethylphosphite led to the corresponding 2-deoxy-iodoglycosyl phosphoramidates in high yield.