2-Oxoderivativesofglycosides,called2-ketoglycosidesorglycoside2-uloses,arebiologicallyimportantincarbohydratemetabolismandareveryusefulinsynthesisofbranched-chainsugarsandaminosugars.Verylittleisknownoftheirchemistrybecauseofthehighsusceptibilityofthesecompoundstodegradationinsolution,andinparticulartheirinstabilitytobase.Thusitisimportanttostudythereactivitiesof2-ketoglycosides.Inapreviouspaper,wereportedthetransformationof2-ketoglycosidesinpyridinesolution.Duringthetransformationof2-and3-ketoglycosides,ademethoxylationreactionoftheenolintermediatewasshowntotakeplacesimultaneouslywitheliminationtogivehex-1-enopyran-3-ulose.
