Elaboration of D-(-)-ribose into a tricyclic, natural product-like scaffold.

The construction of natural product-like, tricyclic compounds is reported. Starting from a D-(-)-ribose-derived dihydrofurane, the tricyclic scaffold is prepared via an intramolecular hetero-Diels-Alder reaction. The reaction proceeds with very high diastereoselectivity through an endo transition state, as established on the basis of X-ray structural analysis of the products. Further modification and derivatization of the obtained products is described.