| Abstract
| - Lewis acid-catalyzed dimerization of mono- and disaccharidic per-O-acetylated glycals gave di- andtetrasaccharidic O-acetylated C-glycosides, respectively. 2,3-Enopyranosyl cyanides were obtainedfrom per-O-acetylated glycals by a new, mild anomeric SN‘-acetoxy displacement with Hg(CN)2/HgBr2/TMSCN. Per-O-acetylated 2-C-2-deoxy-pyranoses were converted into pyranosyl cyanidesby the same reagent. An unprecedented acetic acid elimination from dimers with d-galacto- andl-fuco-configurations accompanied the SN-displacement under those conditions. A new set of 1HNMR coupling constants for 2,3-enopyranosyl systems was used for configurational assignment ofcomplicated tetrasaccharide mimics.
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