STEREOCONTROLLED FACILE SYNTHESIS AND BIOLOGICAL EVALUATION OF (3 ' S) AND (3 ' R)-3 '-AMINO (AND AZIDO)-3 '-DEOXY PYRANONUCLEOSIDES

Abstract

This article describes the synthesis of (3'S) and (3'R)-3'-amino-3'-deoxy pyranonucleosides and their precursors (3'S) and (3'R)-3'-azido-3'-deoxy pyranonucleosides. Azidation of 1,2:5,6-di-O-isopropylidene-3-O-toluenesulfonyl-alpha-D-allofuranose followed by hydrolysis and subsequent acetylation afforded 3-azido-3-deoxy-1,2,4,6-tetra-O-acetyl-D-glucopyranose, which upon coupling with the proper silylated bases, deacetylation, and catalytic hydrogenation, obtained the target 3'-amino-3'-deoxy-beta-D-glucopyranonucleosides. The desired 1-(3'-amino-3'-deoxy-beta-D-allopyranosyl) 5-fluorouracil was readily prepared from the suitable imidazylate sugar after azidation followed by a protection/deprotection sequence and reduction of the unprotected azido precursor. No antiviral activity was observed for the novel nucleosides. Moderate cytostatic activity was recorded for the 5-fluorouracil derivatives.