Exploitation of in Situ Generated Sugar-Based Olefin Keto-Nitrones: Synthesis of Carbocycles, Heterocycles, and Nucleoside Derivatives

Application
of intramolecular 1,3-dipolar nitrone cycloaddition
reaction on carbohydrate-derived precursors containing an olefin functionality
at C-1 or C-3 or C-5 and a nitrone moiety at C-2 or C-3 as appropriate
has resulted in the formation of structurally new cycloaddition products
containing furanose-fused oxepane, thiepane, azepane, cyclopentane,
cycloheptane, tetrahydrofuran, and pyranose-fused tetrahydrofuran
rings. The structure and stereochemistry of these products have been
characterized by spectral as well as single-crystal X-ray analyses.
Two of the compounds have been transformed to the bicyclic nucleoside
derivatives applying Vorbrüggen reaction conditions.