Synthesis of 5a-carba-hexopyranoses and hexopyranosylamines, as well as 5a,5a'-dicarbadisaccharides, from 3,8-dioxatricyclo[4.2.1.0(2,4)]nonan-9-ol: glycosidase inhibitory activity of N-substituted 5a-carba-beta-gluco- and beta-galactopyranosylamines, and derivatives thereof.

Since glycosidase and glycosyltransferase inhibitors, composed of carba-sugars, have recently attracted much attention, it is desirable to develop effective preparative routes for provision of new carba-sugar derivatives of potential biological interest. 1,2:3,6-Dianhydro-5a-carba-alpha-glucopyranose was here chosen for study of synthetic utility, and demonstrated to be a promising intermediate for supplying several carba-beta-glycosylamines and N-linked dicarba-oligosaccharides. An N-linked 5a,5a'-dicarbalactose derivative obtained here was found to be a strong alpha-galactosidase inhibitor (IC50 1.2 microM, green coffee beans).

Potent and specific sialyltransferase inhibitors: imino-linked 5a'-carbadisaccharides.

Methyl 5a'-carba-beta-lactoside, imino-linked, has been shown to possess potent and specific inhibitory activity (IC50 = 185 microM) toward rat recombinant alpha2,3-sialyltransferase.