206127-75-5

Upstream product

• 206195-07-5 isopropyl 7-chloro-6,7-epoxy-1,2:3,4-di-O-isopropylidene-α-D-galacto-octopyranuronate 
• 120449-66-3 isopropyl 6-deoxy-7-oxo-1,2:3,4-di-O-isopropylidene-α-D-galacto-octopyranuronate 
• 4933-77-1 (3aR,5S,5aR,8aS,8bR)-2,2,7,7-Tetramethyl-tetrahydro-bis[1,3]dioxolo[4,5-b;4',5'-d]pyran-5-carbaldehyde 
• 67-56-1 methanol 
• 206127-71-1 isopropyl 7-[[(1'S)-1'-phenylethyl]amino]-6,7-dideoxy-1,2:3,4-di-O-isopropylidene-D-glycero-α-D-galactooctopyranuronate 

Relevant academic research and scientific papers

Synthesis of new glycosyl-α-aminoacid derivatives for glycopeptide chemistry

The synthesis of new N- or C-protected glycosyl-α-aminoacids and their use to prepare new glycopeptides is described. The overall synthetic strategy to obtain these new α-aminoacid chirons involves four distinct steps from dialdoses: (1) a diastereoselective Darzens reaction between the potassium anion derived from isopropyl dichloroacetate and a suitable protected dialdose, (2) the one-pot transformation of the so-obtained isopropyl glycosyl-α-chloroglycidic ester with magnesium iodide, then sodium hydrogenosulfite, into an isopropyl glycosyl-α-ketoester, (3) the reductive amination of the α-ketoester with (S)-α-methylbenzylamine and an hydrogenating reagent, (4) N- or C-selective deprotection and further peptidic coupling.

A novel versatile glycosyl α-aminoacid derivative for glycopeptidic chemistry

The chain extension with an α-ketoester unit at C-6 of 1,2:3,4-di-O-isopropylidene-α-D-galacto-hexodialdo-1,5-pyranose 1 followed by a catalytic reductive amination of the α-keto group led to the novel protected 2-(1′,2′:3′,4′-di-O-isopropylidene-6′-deoxy- α-D-galactopyranosyl) glycine diastereomers 6 and 6′ which are easy to separate. Chemoselective removal of N- or C-protecting groups at the α-aminoacid moiety allowed subsequent insertion of these 6-deoxy-α-D-galactopyranosyl glycine residues into a peptide chain.