Development of Adamantan-1-yl-methoxy-Functionalized 1-Deoxynojirimycin Derivatives as Selective Inhibitors of Glucosylceramide Metabolism in Man

In this article, we present a straightforward synthesis of adamantan-1-yl-methoxy-functionalized 1-deoxynojirimycin derivatives. The used synthetic routes are flexible and can be used to create a wide variety of lipophilic mono- and difunctionalized 1-deoxynojirimycin derivatives. The compounds reported here are lipophilic iminosugar based on lead compound 4, a potent inhibitor of the three enzymes involved in the metabolism of the glycosphingolipid glucosylceramide. Iminosugar-based inhibitors of glucosylceramide synthase, one of these three enzymes, have attracted increasing interest over the past decade due to the crucial role of this enzyme in glycosphingolipid biosynthesis. Combined with the fact that an increasing number of pathological processes are being linked to excessive glycosphingolipid levels, glucosylceramide synthase becomes a very attractive therapeutic and research target. Our results presented here demonstrate that relocating the lipophilic moiety from the nitrogen atom to other positions on the 1-deoxynojirimycin ring system does not lead to a more potent or selective inhibitor of glucosylceramide synthase. The beta-aza-C-glycoside analogue (17) retained the best inhibitory potency for glucosylceramide synthase and is a more potent inhibitor than the therapeutic agent N-butyl-1-deoxynojirimycin (3), marketed as treatment for Gaucher disease under the commercial name Zavesca.