The use of levoglucosenone and isolevoglucosenone as templates for the construction of C-linked disaccharides

Because of their functionalities (enone, ketone, and acetal) and their bicyclic structure (steric factors), levoglucosenone (1,6-anhydro-3,4-dideoxy-β-d-glycero-hex-3-enopyran-2-ulose) and isolevoglucosenone (1,6-anhydro-2,3-dideoxy-β-d-glycero-hex-3-enopyran-4-ulose) are useful templates for the convergent and combinatorial synthesis of (1→2), (1→3), and (1→4)-linked C-disaccharides in reactions combining them with sugar-derived carbaldehydes. Synthetic methods relying on conjugate nucleophilic additions of these enones, their combination with aluminum reagents and aldehydes (Baylis–Hillman reaction) and modified Takai–Hiyama–Nozaki–Kishi couplings of enol triflates derived from them with sugar-derived aldehydes are reviewed. Highly stereoselective methods have thus been developed. These allow the generation of disaccharide mimetics with a high molecular diversity.