Toward Orthogonal Preparation of Sequence-Defined Monodisperse Heteromultivalent Glycomacromolecules on Solid Support Using Staudinger Ligation and Copper-Catalyzed Click Reactions

The investigation of heteromultivalent interactions of complex glycoligands and proteins is critical for understanding important biological processes and developing carbohydrate-based pharmaceutics. Synthetic glycomimetics, derived by mimicking complex glycoligands on a variety of scaffolds, have become important tools for studying the role of carbohydrates in chemistry and biology. In this paper, we report on a new synthetic strategy for the preparation of monodisperse, sequence-defined glycooligomers or so-called precision glycomacromolecules based on solid phase oligomer synthesis and the Staudinger ligation. This strategy employs a solid-supported synthetic approach using a novel carboxy-functionalized building block which bears a functional handle required for Staudinger ligation on solid support. Furthermore, we combined Staudinger ligation and copper catalyzed azide alkyne cydoaddition (CuAAC) reactions to synthesize heteromultivalent glycooligomers on solid support for the first time, demonstrating the utility of this approach for the synthesis of heterofunctional glycomacromolecules.