Synthesis of 2-O-Ethyl Analogues of 5′-Azido- and 5′-Amino-2′,5′-dideoxyuridines as New Antiviral Agents

Abstract

2-O-Ethyluracil derivatives 3a–d have been silylated with HMDS and condensed in the presence of TMS-triflate with a 5-azido sugar to give the corresponding β-nucleosides 5a–d and their α-anomers 6a–d; deprotection afforded 7 and 8, and the 5′-amino derivatives 9a,b could be obtained by treatment of the corresponding 5′-azido nucleosides with triphenylphosphine in pyridine.