C-Glycosyl Nucleosides. II. Reaction of Sugar Aldehyde with Acetylenic Grignard Reagents

Abstract

Reaction of acetylenic Grignard reagents with 2, 3 : 4, 5-di-o-isopropylidene-aldehydo-D-ribose (I) or 2, 4 : 3, 5-di-o-benzylidene-aldehydo-D-ribose (VII) afforded 3-epimeric heptyne derivatives (II, III and VIII, IX). The configuration of these compounds was determined from nuclear magnetic resonance and mass spectra.