Stereoselective synthesis of protected 3-amino-3,6-dideoxyaminosugars†
Joaquim Nebot,Pedro Romea,Fèlix Urpí
Organic & Biomolecular Chemistry Pub Date : 06/13/2012 00:00:00 , DOI:10.1039/C2OB25793A
Abstract

New syntheses of densely functionalized protected derivatives of 3-amino-3,6-dideoxyaminosugars have been accomplished in an efficient and straightforward manner. The key step of such approaches involves a highly stereoselective titanium-mediated aldol addition of a chiral α-bromo ketone, easily available from lactate esters, to crotonaldehyde. Further functional group transformations, including a new regioselective Staudinger–aza-Wittig reaction of an azidodiacetate, afford in a few steps and high yield the desired carbohydrates as advanced intermediates capable of participating in subsequent glycosylation reactions.

Graphical abstract: Stereoselective synthesis of protected 3-amino-3,6-dideoxyaminosugars