13 R= AC predominantly in acidic solution, leads to 5-hydroxymethylfurfura12. The l-deoxy- 2, 3-hexodiulose 5 has not yet been detected and its formation as an intermediate has only been postulated. Attempts have been made to synthesise 5. Starting with 3, 6-anhydro-4, 5-~- isopropylidene-D-mannitol, Fisher and co-workers4 obtained crystalline l-deoxy-4, 5-O- isopropylidene-o-erythro-2, 3-hexodiulose. After removing the protecting group under ...
