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

Abstract

Because of their functionalities (enone, ketone, and acetal) and their bicyclic structure (steric factors), levoglucosenone (1,6-anhydro-3,4-dideoxy-beta-D-glycero-hex-3-enopyran-2-ulose) and isolevoglucosenone (1,6-anhydro-2,3-dideoxy-beta-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.