Targeted allylation and propargylation of galactose-containing polysaccharides in water

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Ann-Sofie Leppänen, Chunlin Xu, Kirsti Parikka, Patrik Eklund, Rainer Sjöholm, Harry Brumer, Maija Tenkanen, Stefan Willför
Publication year: 2014
Journal: Carbohydrate Polymers
Journal acronym: Carbohydr. Polym.
Volume number: 100
Start page: 46
End page: 54
ISSN: 1879-1344


Abstract

Galactose units of spruce galactoglucomannan (GGM), guar galactomannan (GM), and tamarind (galacto)xyloglucan (XG) were selectively allylated. Firstly aldehyde functionalities were formed at the C-6 position via enzymatic oxidation by galactose oxidase. The formed aldehydes were further derivatized by an indium mediated Barbier-Grignard type reaction, resulting in the formation of homoallylic alcohols. In addition to allylic halides, the same reaction procedure was also applicable for GGM, when using propargyl bromide as halide. All reaction steps were done in water, thus the polysaccharides were modified in a one-pot reaction. The formation of the allylated, or propargylated, product was identified by MALDI-TOF-MS. All polysaccharide products were isolated and further characterized by GC-MS or NMR spectroscopy. By this chemo-enzymatic process, we have demonstrated a novel method for derivatization of GGM and other galactose-containing polysaccharides. The derivatized polysaccharides are potential platforms for further functionalizations.


Keywords

Allylation, Guar galactoglucomannan, Indium mediated, MALDI-TOF-MS, Polysaccharides, Propargylation, Spruce galactoglucomannan, Tamarind xyloglucan

Last updated on 2019-21-09 at 03:14