Czifrák K, Gyóllai V, Kövér KE, Somsák L. 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.
Carbohydr Res 2011;
346:2104-12. [PMID:
21802663 DOI:
10.1016/j.carres.2011.07.001]
[Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 06/29/2011] [Accepted: 07/01/2011] [Indexed: 10/18/2022]
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.
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