Mono- Vs. Di-flourous tagged Glucosamines for Iterative Oligosaccharide Synthesis.
Fluorous-tagged protecting groups are attractive tools for elongating carbohydrate chains in oligosaccharide synthesis. To eliminate the accumulation of failed sequences during automated oligosaccharide synthesis conditions, an additional C(8)F(17) ester derived protecting group was attached to the glycosyl donor to better retain the desired doubly-tagged glycosylation product on fluorous solid phase extraction (FSPE) cartridges. Initial studies show that the double-fluorous-tagging strategy offers a robust enough separation using a commercial FSPE cartridge using simple gravity filtration to separate the desired product from the singly-fluorous-tagged starting materials and their decomposition products. In addition, removal of the fluorous acetate and its byproducts after sodium methoxide treatment and neutralization required only dissolution of the desired sugar in toluene and subsequent removal of the toluene layer from the denser fluorous byproducts.
2756 Gilman, Department of Chemistry and the Plant Sciences Institute, Iowa State University, Ames, IA 50011 USA.
Gisun
G
Park
Kwang-Seuk
KS
Ko
Aleksandra
A
Zakharova
Nicola L
NL
Pohl