A synthesis of 2-deoxy- d- arabino-hexitol and its oxidation to 5-deoxy- d- hreo-hexulose (“5-deoxy- d-fructose”) using immobilized cells of Gluconobacter oxydans

Abstract

2-Deoxy- d- arabino-hexitol ( 6) was obtained by borohydride reduction of 2-deoxy- d- arabino-hexose ( 5). The synthesis of 5, starting from 2,3:4,5-di- O-isopropylidene- d-arabinitol ( 1), was achieved by a one-carbon chain-elongation involving formylation of the Grignard reagent derived from 1-bromo-1-deoxy-2,3:4,5-di- O-isopropylidene- d-arabinitol ( 2), using lithium formate, followed by hydrolytic removal of the isopropylidene groups. Immobilized cells of Gluconobacter oxydans (ATCC 15178) selectively oxidized 6 to give 5-deoxy- d- threo-hexulose ( 7) in 65% yield (∼9% overall yield from 1).