Synthesis of C2-symmetrical polyhydroxyazepanes as inhibitors of glycosidases

Two C2-symmetrical bis-epoxides were prepared from and were subjected to nucleophilic displacements with allylamine and benzylamine. Initial intermolecular epoxide opening, followed by a preferred intramolecular 7-endo-tetragol cyclization, afforded protected polyhydroxyazepanes as major products. Compound 15 was found to inhibit seven different glycosidases with Ki in the micromolar range.