340699-20-9

Upstream product

• 23885-38-3 3-O-benzyl-1,2:5,6-di-O-isopropylidene-α-D-gulofuranoside 
• 112670-07-2 (2R,3R,4S,5R)-3-Benzyloxy-2,4,5,6-tetrahydroxy-hexanal 
• 237749-86-9 (2R,3S,4S)-4-Benzyloxy-4-(1H-imidazol-4-yl)-butane-1,2,3-triol 
• 14686-88-5 3-O-acetyl-1,2:5,6-di-O-isopropylidene-α-D-erythro-hex-3-enofuranose 
• 26775-14-4 3-O-acetyl-1,2:5,6-di-O-isopropylidene-α-D-gulofuranose 

Relevant academic research and scientific papers

Stereoisomeric imidazolo-pentoses - Synthesis, chiroptical properties, and evaluation as glycosidase inhibitors

The syntheses of all four imidazolo-piperidino-pentoses in the L-series ent-2 to ent-5, and of three out of the four possible stereomers in the D-series 3, 4, and 5, are reported. The linear imidazolo sugar precursors were prepared, either by double condensation of formamidine with protected aldohexoses, or by nucleophilic addition of a lithiated imidazole derivative to protected aldotetroses. Cyclisation of these linear imidazolo-carbohydrates was performed by intramolecular SN2 reactions. These were followed by deprotection to the target molecules. The four pairs of opposite enantiomers showed pronounced mirror-image-type Cotton effects in their CD spectra. All stereomers of the D-series show a negative rotatory power ([α]D), while the stereomers of the L-series show a positive one. None of the eight imidazolo sugars inhibited the replication of HIV-1. Some of them proved to be rather selective but only moderately potent inhibitors of α-glycosidases, as determined by Michaelis-Menten kinetics.

Improved double epimerisation of (D)-glucose into (D)-gulose and the synthesis of (D)-xylo-imidazolopiperidinose

Rhodium/alumina catalysed cis-hydrogenation of the known enol-acetate 7 proceeded quantitatively and with complete stereoselectivity leading to the D-gulose derivative 8. Several reaction steps permitted transformation of 8 into the target D-xylo-imidazolopiperidinose ent-4 molecule, i.e, the enantiomer of the already known imidazolo-sugar 4.