Selective disaccharide hydrolysis with microgel catalysts.

by Striegler, Susanne

The hydrolysis of non-activated disaccharides representing the most frequent glycosidic linkages and configurations is achieved using polyacrylate microgels with an embedded binuclear metal complex. The microgels hydrolyze the b -glycosidic bond in cellobiose yielding up to 25 µg L-1 of glucose over 72 h in weakly alk. solution In the same amount of time, the catalyzed maltose hydrolysis yields about half of the glucose amounts indicating a preference of the catalysts for 1?4 ß - over 1?4 a -glycosidic bonds. This observation is made for all microgel catalysts explored and demonstrated to include heterodisaccharides, such as lactose. The observation is further supported by a computational anal. of the binding interactions between the immobilized metal complex and the resp. disaccharide. The computation reveals the geometry of a putative transition state of the reaction and the location of intermol. H-bonds that restrict movement and rotation of the glycosyl moieties during hydrolysis. The combined results of this study pave the way for the development of advanced catalysts capable to hydrolyze non-activated oligosaccharides and may open a platform for the transformation of biorenewable resources into valuable synthons.