Patent ID: 7439351
Filing Date: 2008-10-21
Classification: C07D,C07H

Abstract:
1. A method for the preparation of 2′- or 3′-deoxy- and 2′,3′-dideoxy-β-L-pentofuranonucleoside compounds of formula I: in which B represents purine or pyrimidine base selected from the group consisting of adeninyl, guaninyl, hypoxanthinyl, uracilyl, thyminyl, cytosinyl, 5-halo-uracilyl and 5-halo-cytosinyl; R R at least one of R comprising the following steps: 1) a compound of formula (II) is condensed with the base B′ with an appropriate coupling reagent in order to obtain the compound of formula (III) according to the scheme wherein: R′ R′ X is a leaving group selected from Cl, Br, I, a C B′ is a purine or pyrimidine base B which is protected by an amino protecting group selected from the group consisting of an acyl, a benzoyl, a benzyl and a silyl group when necessary, 2) the R′ 3) optionally, the OH group at the 2′ position is removed by a deoxygenation reaction; and 4) where appropriate, the R′