Stereoselective synthesis of 4′-selenonucleosides using the Pummerer glycosylation reaction
作者:Kumarasamy Jayakanthan、Blair D. Johnston、B. Mario Pinto
DOI:10.1016/j.carres.2008.02.014
日期:2008.7
The syntheses of four selenonucleosides, namely 4 '-O-selenoadenosine, -cytidine, -thymidine, and -uridine are described. Commercially available D-ribonolactone was converted to the key intermediate 1,4-anhydro-4-seleno-D-ribitol in seven steps in overall excellent yield. Oxidation of the seleno-D-ribitol with MCPBA gave a single diastereomeric selenoxide in excellent yield, which upon Pummerer reaction in the presence of silylated purine or pyrimidine bases gave stereoselectively the corresponding 4'-beta-selenonucleosides. The stereochemistry at the anomeric center was determined by means of 1D-NOE experiments. (C) 2008 Elsevier Ltd. All rights reserved.