Résumé
Deoxygenation of thiazolylketose acetates using SmI
2–(CH
2OH)
2 or TMSOTf–Et
3SiH affords thiazolyl
C-glycosides with opposite α/β ratios. Examination of the thiazolyl α- and β-
C-ribofuranoside pair by NOE experiments reveals that the earlier configuration assigned to one of these isomers has to be revised. Having prepared authentic anomeric α- and β-ribofuranose aldehydes from the corresponding thiazolyl
C-glycosides by cleavage of the thiazole ring, each aldehyde was transformed into (1→6)-
C-disaccharides via Wittig olefination with a galactose 6-phosphorane.
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