855996-96-2

Upstream product

• 84380-10-9 4,7,8,9-tetra-O-acetyl-N-acetylneuraminic acid methyl ester 
• 108-95-2 phenol 
• 67670-69-3 N-acetyl-4,7,8,9-tetra-O-acetyl-2-chloro-2-deoxyneuraminic acid methyl ester 
• 6931-68-6 methyl 5-acetamido-2,4,7,8,9-penta-O-acetyl-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate 

Downstream Products

• 15964-33-7 phenyl (5-acetamido-3,5-dideoxy-D-glycero-β-D-galacto-non-2-ulopyranosylonic acid) 
• 15964-35-9 (2R,4S,5R,6R)-5-Acetylamino-4-hydroxy-2-phenoxy-6-((1R,2R)-1,2,3-trihydroxy-propyl)-tetrahydro-pyran-2-carboxylic acid methyl ester 

Relevant academic research and scientific papers

Stereocontrolled Synthesis of Phenolic α-d-Glycopyranosides

Adopting the ‘remote activation concept’ toward stereocontrolled glycoside synthesis with minimal use of protection groups, a general synthesis of phenolic 1,2-cis glycopyranosides is reported, as exemplified by aryl α-d-galacto-, α-d-gluco- and 2-azido α-d-glucopyranosides among others using glycosyl donors bearing an anomeric (3-bromo-2-pyridyloxy) group and catalyzed by methyl triflate.

Glycosylation with ulosonates under Mitsunobu conditions: Scope and limitations

A systematic study was performed by using Mitsunobu conditions (diethyl azodicarboxylate, Ph3P or n-Bu3P in THF or CH3CN) for glycosylations with methyl 3,4,5,7-tetra-O-benzoyl-α-d-gluco-hept-2-ulopyranosonate. From a set of 47 O-, N-, S- and C-nucleophiles, phenols and N-hydroxy compounds with a pKa of 5-8, phthalimide, benzotriazole, 6-chloropurine, an oxazolidinedione and several tetrazoles with a pKa of 4-8, and thiophenol gave the corresponding products in moderate to very good yields, while C-nucleophiles were unreactive. Trihaloacetanilides underwent O-glycosylation to give O-glycosyl-N-aryl trihaloacetimidates which could not be made by conventional O-imidoylations. All reactions were highly stereoselective to produce the β(d) anomers only. With methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-d-glycero-d-galacto-2-nonulopyranose)onate phenols and benzotriazole resulted in the expected products, but all other nucleophiles failed to react. While these transformations gave anomeric mixtures in a ratio close to 1?:?1 at room temperature, the α-selectivity increased to 92?:?8 at -30 °C. An o-nitrophenyl sialoside was converted to a spiro-benzoxazinone derivative by reduction of the nitro group and subsequent spontaneous ring closure.