Patent ID: 7638642
Filing Date: 2009-12-29
Classification: C07H

Abstract:
1. A method for preparing a 2,2-difluoro-2-deoxy-1-oxoribose derivative of formula (I), comprising the steps of: (i) reacting a compound of formula (V) with a biphenylcarbonyl derivative to obtain a compound of formula (IV) having the 3-hydroxy group protected by a biphenylcabonyl group; (ii) reacting the compound of formula (IV) with a base in a mixed solvent essentially comprising water and isolating a resulting 3R-carboxylate enantiomer of formula (III) by filtration; (iii) reacting the compound of formula (III) with an acid to obtain a 5-hydroxy-1-oxoribose derivative of formula (II); and (iv) protecting the 5-hydroxy group of the compound of formula (II) with R wherein, R is R R r R M is sodium or potassium.