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Updated: Jul 10, 2026

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE
Published on: October 16, 2017
Synthesis of branched Man5 oligosaccharides and an unusual stereochemical observation
Nardos Teumelsan1, Xuefei Huang
1Department of Chemistry, The University of Toledo, Toledo, OH 43606, USA.
Abstract:
Branched mannopentaoses were synthesized through two routes. While assembly from the nonreducing end to the reducing end was more convergent with fewer intermediate steps, two diastereomers were obtained. On the other hand, synthesis from the reducing end to the nonreducing end yielded the mannopentaose with the desired stereochemistry as a single isomer. Our results suggest that it is still challenging to reliably predict stereochemical outcome of a glycosylation reaction. It is necessary to thoroughly characterize anomeric configurations of newly formed glycosidic linkages in complex oligosaccharide synthesis.
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