Carbohydrate structures are often complex. Unfortunately, synthesis of the range of sugar combinations precludes the use of a single coupling protocol or set of reagents. Adapting known, reliable bench-chemistry reactions to work via automation will help forward the goal of synthesizing a broad range of glycans. Herein, the preparation of di- and tri-saccharides of alpha 1→2 rhamnan fragments is demonstrated using thioglycoside donors with the development for a solution-phase-based automation platform of commonly used activation conditions using N-iodosuccinimide (NIS) with trimethylsilyl triflate. Byproducts of the glycosylation reaction are shown to be compatible with hydrazine-based deprotection conditions, lending broader functionality to this method as only one fluorous-solid-phase extraction step per coupling/deprotection cycle is required.
Bibliographical noteFunding Information:
Acknowledgements: This work was supported in part by Indiana University and the National Institute of General Medical Sciences (Funder Id: http://dx.doi.org/10.13039/100000057, 5U01GM116248-02). We thank Dr. R. Saliba for his input and assistance with the automation platform and Prof. A. Flood and his research group for use of their Agilent 1200 Preparatory HPLC system.
© 2019 IUPAC & De Gruyter. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. For more information, please visit: http://creativecommons.org/licenses/by-nc-nd/4.0/ 2019.
- automated synthesis