10.1021/jo951641t
The research aimed to synthesize D-fructofuranosides using benzylated and benzoylated ethyl thioglycosides as glycosyl donors for coupling with various carbohydrate acceptors. The study found that these thiofructofuranosides, when promoted by dimethyl(methylthio)sulfonium triflate (DMTST) or N-iodosuccinimide (NIS), were excellent glycosyl donors, yielding disaccharide products in quantitative or near-quantitative yields, which is a rarity in oligosaccharide synthesis. The benzoylated donors predominantly produced α-linked fructofuranosides due to the participation of the 3-O-benzoyl group, while benzylated donors resulted in α/β-mixtures. Key chemicals used in the process included 2-O-acetyl-1,3,4,6-tetra-O-benzoyl-D-fructofuranose, ethyl mercaptan, BF3 etherate, and various carbohydrate acceptors such as 5, 6, and 7. The research concluded that ethyl 2-thio-D-fructofuranosides are superior glycosyl donors, capable of producing oligosaccharide products with high yields, and that the use of NIS as a promoter, particularly at lower temperatures, can enhance the production of β-fructofuranosidic products.
10.1016/0040-4039(96)01614-0
The research focuses on the development of a method for the stereospecific synthesis of fructofuranosides, which are important components of various polysaccharides and possess significant biological functions. The study aimed to address the challenges in forming fructofuranosides using standard glycosylation methods, which often result in low yields or anomeric mixtures. The researchers synthesized two ethyl thioglycosides of D-fructofuranose, compounds 4a and 4b, which were differentially protected at positions 1 and 6. These compounds were used as donors in glycosylation reactions with various acceptors in the presence of iodonium di-sym-collidine perchlorate (IDCP) as a promoter. The study concluded that the developed approach could be a valuable tool for the synthesis of fructofuranosides, especially for the preparation of oligosaccharides with specific anomeric configurations. The chemicals used in the process included D-arabinose for the synthesis of the donors, various acceptors such as compounds 5 through 10, and reagents like IDCP, boron trifluoride etherate, and ethanethiol for the glycosylation reactions.