Enantiospecific synthesis of 1-azafagomine.

For the first time the two enantiomeric forms of the glycosidase inhibitor 1-azafagomine have been synthesised starting from D- and L-xylose. D-Xylose was converted to the 2,3,5-tribenzylfuranose, which upon reductive amination with tert-butyl carbazate gave the protected 1-hydrazino-1-deoxypentitol in high yield. N-acetylation, mesylation of the 4-OH, removal of the Boc group, cyclisation and deprotection gave (+)-1-azafagomine ((+)-1).

Synthesis of substituted chiral piperazones resembling aza-sugars.

(6R)-6-(Hydroxymethyl)piperazin-2-one (1), (6S)-6-(hydroxymethyl)piperazin-2-one (2) and (6S)-6-[(1R, 2S, 3R)-1,2,3,4-tetrahydroxybutyl]piperazin-2-one (3) have been prepared in optically pure forms starting from D-glucosamine hydrochloride (4). The compounds (1-3) were tested for glycosidase inhibition.