title: Ritter-type reaction of C-(1-bromo-1-deoxy-D-glycopyranosyl)formamides and its application for the synthesis of oligopeptides incorporating anomeric α-amino acids.
abstract: O-Peracetylated or -perbenzoylated C-(1-bromo-1-deoxy-D-glycopyranosyl)formamides of D-gluco, D-galacto, and D-arabino configuration were reacted with Ag(I)-salts or HgO in nitrile solvents to give N-acyl-1-cyano-D-glycopyranosylamines with an axial C-N bond at the anomeric centre. In the presence of HgBr(2), Hg(CN)(2), or InCl(3) the anomer of the above glycosylamine with an equatorial C-N bond was also isolated or detected. In CH(3)NO(2) solutions as few as 5-10 equiv of the nitrile were sufficient to get acceptable yields for the products. Under similar conditions N-substituted C-(2,3,4,6-tetra-O-acetyl-1-bromo-1-deoxy-β-D-galactopyranosyl)formamides gave anomeric spiro-oxazoline derivatives which, upon mild acidic hydrolysis, opened up to di- and tripeptides of anomeric α-amino acids.
authors.affiliation: Department of Organic Chemistry, University of Debrecen, POB 20, H-4010 Debrecen, Hungary.
authors.forename: Katalin
authors.initials: K
authors.lastname: Czifrák
authors.forename: Viktor
authors.initials: V
authors.lastname: Gyóllai
authors.forename: Katalin E
authors.initials: KE
authors.lastname: Kövér
authors.forename: László
authors.initials: L
authors.lastname: Somsák
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D005559:Formamides / Q000737:chemistry*; D009842:Oligopeptides / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D005559:Formamides; D009842:Oligopeptides