Dérivés du 2,5-anhydro-D-ribononitrile N-oxyde

When the mixture of syn and anti isomers of 2,5-anhydro-3,4-O-isopropylidene-aldehydo-D-ribose oxime was treated with chlorine, two gem-chloronitroso derivatives, epimers at C-1, were formed; they were in equilibrium with three dimers and were transformed by prototropy into the corresponding hydroxymoyl chloride. Treatment of the latter compound with a base gave a nitrile oxide which forms a dimer, or undergoes transformation into a furazan, or reacts with phenylacetylene to give a mixture of an acetylenic oxime and of the corresponding 3-glycosyl-5-phenylisoxazole.