77489-38-4

Upstream product

• 4779-31-1 Z-Asp-OBn 
• 14152-97-7 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate 
• 98300-76-6 2,3,4,6-tetra-O-acetylglucopyranosyl 1-amine 
• 41355-50-4 2,3,4,6-tetra-O-acetyl-D-glucosyl-1-amine 
• 64578-11-6 N-(benzyloxycarbonyl)-L-aspartic acid-4-chloride-1-benzyl ester 
• 4451-36-9 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl chloride 
• 20379-61-7 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl azide 
• 525589-11-1 2-methyl-4,5-dihydro-(3,4,6-tri-O-acetyl-1,2-dideoxy-α-D-glucopyrano)[2,1-d]-2-oxazoline 

Relevant academic research and scientific papers

Synthesis of α-N-linked glycopeptides

A practical synthesis of Nα-fluorenylmethoxycarbonyl- Nγ-(2,3,4,6-tetra-O-acetyl-α-D-glycopyranosyl)-L- asparagine in the gluco and galacto series has been achieved by using the methodology developed by DeShong and co-workers. The resulting α-N-linked glycosyl amino acids were used in a linear approach to the synthesis of glycopeptides featuring the unnatural α-N-glycosyl linkage. Activation conditions for both C- and N-terminus elongation in solution have been defined. The main side-reaction encountered was the formation of cyclization by-products (aspartimide) from the activated amino acid during C-terminus elongation. Appropriate condensing agents were identified, which allowed a high yield of dipeptide formation and no epimierization of the glycosyl amino acids. Conditions for sugar deacetylation have also been optimized. Solid-phase synthesis (Fmoc protocol) conditions were explored and PyBROP was found to be the reagent of choice for the activaton of glycosyl amino acids. The synthesis of more complex α-N-linked glycopeptides has thus become feasible, which will allow the properties of these neo-glycoconjugates to be studied. Copyright

Synthesis of glycosylamines from glycosyl isothiocyanates and bis(tributyltin) oxide

The synthesis of glycopyranosylamines is described from the reaction of glycopyranosyl isothiocynates with bis(tributyltin) oxide. The method is simple and efficient allowing, under very mild conditions, the synthesis of N-acyl glycopyranosylamines in one pot. The reactions were performed using both 2-deoxy-2-iodo glycopyranosyl isothiocyanates and glycopyranosyl isothiocyanates derived from mono- and disaccharides. Anomerization was observed when the starting materials were α-glycopyranosyl derivatives. The methodology has also been applied for the preparation of several glycosyl amino acids.

Neighbouring group participation of C-6 substituents of glucose derivatives on the stereoselectivity of the N-glycosidic linkage of glycopeptides

The first example of a glycopeptide with a direct N-α-glycosidic linkage between the trisaccharide and the amino acid residue was found in the glomerular basement membrane of rats. In connection with the total synthesis of nephritogenoside, glycosyl azides with different protecting groups and carbohydrate chain lengths are synthesized, reduced to the corresponding glycosyl amines and coupled with Z-Asp-OBzl. Remarkable differences in the α:β ratio of the condensation products are observed, caused by neighbouring group participation.

SYNTHESIS OF GLYCOSYLAMIDES AND 4-N-GLYCOSYL-L-ASPARAGINE DERIVATIVES

A new synthesis of acylated glycosylamides by use of the reaction of acylglycosyl isothiocyanates with carboxylic acids catalyzed by triethylamine is described.Condensation with 1-benzyl N-(benzyloxy)carbonyl-L-aspartate, as carboxyl-containing compound,