221012-71-1

Upstream product

• 108740-74-5 phenyl 2,3,4-tri-O-acetyl-1-thio-α-L-rhamnopyranoside 
• 3162-96-7 4,6-O-benzylidene-1-O-methyl-α-D-glucopyranoside 
• 30021-94-4 1,2,3,4-O-tetraacetyl-α-L-rhamnopyranose 
• 97-30-3 methyl-alpha-D-glucopyranoside 
• 1125-88-8 benzaldehyde dimethyl acetal 
• 113893-72-4 2,3,4-tri-O-acetyl-L-rhamnopyranosyl trichloroacetimidate 

Relevant academic research and scientific papers

Sonochemistry: A powerful way of enhancing the efficiency of carbohydrate synthesis

Using sonication as a means of facilitating organic reactions in carbohydrate chemistry was explored under the conditions used for traditional organic synthesis. An array of representative reactions, including hydroxy group manipulation (acylation, protection/deprotection, acyl group migration), thioglycoside synthesis, azidoglycoside synthesis, 1,3-dipolar cycloaddition and reductive cleavage of benzylidene, commonly used in the synthesis of carbohydrate derivatives was examined. A series of glycosylation reactions that employ thioglycosides, glycosyl trichloroacetimidate, glycosyl bromide and glycosyl acetate as the glycosyl donors was also examined. Our results demonstrate that sonication can significantly shorten the reaction time, enhance the reactivity of reactant and lead to superior yield and excellent stereoselectivity. More importantly, a general protocol of glycosylation may finally be developed. Sonication is compatible to the conditions used for traditional organic synthesis. We believe that sonication can also be applied to other areas of synthetic processes.

Synthesis and nmr characterisation of methyl mono- and DI-0-α-L-rhamnopyranosyl-α-d-glucopyranosiduronic acids

The synthesis and NMR characterisation of methyl mono- and di-O-α-L-rhamnopyranosyl-α-D-glucopyranosiduronic acids 1-6 are described. Two commercial starting products were used: methyl α-D-glucopyranoside 7 for the preparation of 1 and 2, and methyl (R)-4,6-O-benzylidene-α-D-glucopyranoside 8 for 3-6. Oxidation reaction of the hydroxymethyl group of glucose to a carboxylic acid group was performed by sodium hypochlorite 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)-mediated procedure after the coupling reaction. Glycosylation was carried out using the trichloroacetimidate approach with trimethylsilyl trifluoromethanesulfonate (TMSOTf) as promoter, resulting in a completely stereoselective formation of the a glycosyl linkage.