Gulose synthesis

Most substrates, with the exception of hydroxypymvate, have a threo configuration of hydroxyl groups at the C-3 and C-4 positions (139). The new stereocenter formed in TK-catalyzed addition is formed in the threo configuration with high diastereo-selectivity (151). Using TK-catalyzed condensations of hydroxypymvic acid with a number of aldehydes a practical preparative synthesis of L-idose [5934-56-5], L-gulose [6027-89-0], 2-deoxy-L-xylohexose, and... 

Minster and Hecht16 reported a synthesis of a derivative of L-gulose (9) from D-glucose (25) that takes advantage of the ready availability of... 

By treatment of D-gulose (XVII) or D-idose (XVIII) with warm aqueous barium hydroxide solution Van Ekenstein and Blanksma were able to isolate D-sorbose (II) with a melting point of 165° and [< ]d + 42.9° in water. The aldoses were prepared from D-gulonic and D-idonic lactones obtained by the cyanohydrin synthesis from D-xylose. 

Gomez, A M, Moreno, E, Valverde, S, Lopez, J C, Stereodivergent synthesis of carbasugars from d-mannose. Syntheses of 5a-carba-alpha-D-allose, beta-L-talose, and alpha-L-gulose pentaacetates, Synlett, 891-894, 2002. 

Applying the same route, d- and L-mannose were obtained in a five-step synthesis (39% overall yield) from furfural. Similarly, the same methodology was extended to the preparation of d- and L-gulose and d- and L-talose (19% yield) [229]. 

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