Monomers derived from glucose and galactose, which contain an endocyclic alkene (in the sugar ring) and a terminal alkyne, underwent a cascade polymerization to prepare new polymers with the ringopened sugar incorporated into the polymer backbone. Polymerizations were well-controlled, as demonstrated by a linear increase in molecular weight with monomer-toinitiator ratio and generally narrow molecular weight dispersity values. The living nature of the polymerization was supported by the preparation of a block copolymer from two different sugar-based monomers. The resulting polymers were also fully degradable. They underwent fast and complete depolymerization to small molecules under acidic conditions.

Enyne monomers derived from D‐xylose underwent living cascade polymerizations to prepare new polymers with a ring‐opened sugar and degradable linkage incorporated into every repeat unit of the backbone. Polymerizations were well‐controlled and had living character, which enabled the preparation of high molecular weight polymers with narrow molecular weight dispersity values and a block copolymer. By tuning the type of acid‐sensitive linkage (hemi‐aminal ether, acetal, or ether functional groups), we could change the degradation profile of the polymer and the identity of the resulting degradation products. For instance, the large difference in degradation rates between hemi‐aminal ether and ether‐based polymers enabled the sequential degradation of a block copolymer. Furthermore, we exploited the generation of furan‐based degradation products, from an acetal‐based polymer, to achieve the release of covalently bound reporter molecules upon degradation.

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A wide range of stable vinyl selenone-modified furanosides has been synthesized for the first time. These 2π-partners undergo 1,3-dipolar cycloaddition reactions with a wide range of organic azides to afford enantiopure trisubstituted triazoles. Furanosyl rings opened up during triazole synthesis to generate polyfunctionalized molecules, ready to undergo further transformations. This strategy is one of the most convenient methods for the synthesis of enantiopure 1,4,5-trisubstituted 1,2,3-triazoles where the chiral components are attached to C-4 or C-5 position of triazole ring. These triazoles are formed in a regioselective manner, and several pairs of regioisomeric triazoles have also been synthesized. The approach affords densely functionalized triazoles, which are amenable to further modifications because of the presence of aldehyde and hydroxyl groups. This powerful and practical route adds to the arsenals of chemists and biologists interested in the synthesis and applications of triazoles.

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