109681-01-8

Upstream product

• 19131-06-7 1,2:5,6-di-O-isoproylidene-3-O-tosyl-α-D-gulofuranose 
• 109680-99-1 Acetic acid (3aR,5S,6S,6aR)-5-{1-[(Z)-hydroxyimino]-2-trityloxy-ethyl}-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl ester 
• 109680-97-9 3-O-acetyl-1,2-O-isopropylidene-6-O-trityl-α-D-galactofuranose 
• 109680-98-0 3-O-acetyl-1,2-O-isopropylidene-6-O-trityl-β-L-arabino-hexofuranos-5-ulose 
• 38166-65-3 3-O-acetyl-1,2:5,6-di-O-isopropylidene-α-D-galactofuranose 
• 109680-96-8 3-O-acetyl-1,2-O-isopropylidene-α-D-galactofuranose 

Downstream Products

• 78698-43-8 5-amino-5-deoxy-L-altropyranose hydrogensulfite adduct 

Relevant academic research and scientific papers

Synthesis of 5-amino-5-deoxy-D-galactopyranose and 1,5-dideoxy-1,5-imino-D-galactitol, and their inhibition of alpha- and beta-D-galactosidases.

A 12-step route is presented starting from 1,2:5,6-di-O-isopropylidene-alpha-D-glucofuranose for the preparation of the title compounds and their L-altro analogues. Their synthesis is based on the reduction with Raney nickel of a protected 5-hydroxyimino derivative of L-arabino-hexofuranos-5-ulose, with the following improvements for the preparation of a D-galactofuranose derivative: oxidation at C-3 with pyridinium dichromate-acetic anhydride, stereospecific reduction of a 3-O-acetyl-hex-3-enofuranose intermediate to the D-gulo derivative, and inversion at C-3 of its 3-tosylate with tetrabutylammonium acetate in chlorobenzene. alpha-D-Galactosidase from coffee beans and from Escherichia coli and beta-D-galactosidase from E. coli and Aspergillus wentii were inhibited with Ki values that ranged from 0.0007 to 8.2 microM. Formation of the enzyme-inhibitor complexes with the D-galactose analogue was on the time-scale of minutes, whereas the D-galactitol analogue showed a slow approach to the inhibition only with alpha-D-galactosidase from coffee beans and beta-D-galactosidase from A. wentii. N-Alkylation of the D-galactitol analogue was detrimental to the inhibition except for beta-D-galactosidase from E. coli and beta-D-glucosidase from almonds, but, even with these enzymes, the observed affinity enhancements were 10(2) to 10(3)-times smaller than those of N-alkylated D-galactosylamine and D-glucosylamine.