Improvement of the stereoselectivity of the glycosylation reaction with 2-azido-2-deoxy-1-thioglucoside donors

Carbohydr Res. 2016 May 13:426:33-9. doi: 10.1016/j.carres.2016.03.021. Epub 2016 Mar 29.

Abstract

2-Azido-2-deoxy-1-thioglucoside donors with an electron withdrawing group at position 6 were employed to study the stereoselectivity of the glycosylation reaction with several acceptors, ranging from unhindered small primary alcohols to other sugars and steroids, using NIS/TfOH as promoter. p-Tolyl 2-azido-3,4-di-O-benzyl-6-O-chloroacetyl-2-deoxy-1-thio-α/β-D-glucopyranoside afforded the higher α-selectivity, showing that a stronger electron withdrawing ester at O-6 influenced the anomeric selectivity towards the 1,2-cis glucosides. The anomeric stereoselectivity was highly dependent on the acceptor.

Keywords: 1,2-cis Glycosides; 2-Azido-2-deoxy-1-thioglucosides; Glycosylation reaction; α-2-Azido-2-deoxy-glucosides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohols / chemistry*
  • Carbohydrate Conformation
  • Carbohydrates / chemistry*
  • Glycosylation
  • Stereoisomerism
  • Steroids / chemistry*
  • Thioglucosides / chemistry*

Substances

  • 2-azido-2-deoxy-1-thioglucoside
  • Alcohols
  • Carbohydrates
  • Steroids
  • Thioglucosides