Synthesis of novel 3-deoxy-3-C-triazolylmethyl-allose derivatives and evaluation of their biological activity

Recently, monosaccharide-triazole conjugates have proved to possess a large variety of useful biological activities. This paper describes synthesis of a new series of 3-deoxy-3-C-triazolylmethyl-allose derivatives. These new compounds are obtained from acetonide-protected 3-deoxy-3-azidomethyl allose and commercial alkynes via Cu(I) catalyzed 1,3-dipolar cycloaddition. The obtained molecular scaffolds differ from those described earlier by the presence of a methylene linker (-CH2-) between the C(3) of allose and the triazole moiety. It was demonstrated that acetonide-protected monosaccharide, 3-deoxy-3-C-(4-phenyl-1H-1,2,3-triazol-1-yl)methyl-1,2:5,6-di-O-isopropylidene-alpha-d-allofuranose, inhibited alpha-L-fucosidase for 26% at 0.1 mM concentration, but a deprotected analog, 3-deoxy-3-C-(4-(4-tert-butylphenyl)-1H-1,2,3-triazol-1-yl)methyl-beta-d-allofuranose, showed 15% inhibition of beta-glucosidase at 1 mM concentration.