O-Oligosaccharidyl-1-amino-1-deoxyalditols as intermediates for fluorescent labelling of oligosaccharides

Janice G. Miller, Vladimir Farkas, Sandra C. Sharples, Stephen C. Fry

Research output: Contribution to journalArticlepeer-review

Abstract

Reducing monosaccharides were efficiently converted to stable 1-amino-1-deoxyalditols (=glycamines; distinguished from glycosylamines by mass-spectrometry) during incubation at 20 degrees C in saturated aqueous NH4HCO3 containing NaCNBH3. Potentially useful by-products included a novel, fully-reduced dimer (the corresponding secondary glycamine) and several relatively long-lived, unreduced products. With increasing incubation time, monomers exceeded dimers. Reducing disaccharides and oligosaccharides underwent similar reactions at their reducing termini; the yield of dimers decreased with increasing oligosaccharide M-r. The O-oligosaccharidyl-1-amino-1-deoxyalditols (OADs) obtained by reductive amination of oligosaccharides reacted readily with lissamine rhodamine sulfonyl chloride to yield OAD-sulforhodamine conjugates linked by a stable sulfonamide bond. Conditions for this reaction were optimised (borate buffer, pH 9.0 - 9.5). The highly fluorescent OAD-sulforhodamine products were purified on a C-18 cartridge. They were electrophoretically immobile at pH 2.0 and 6.5, and migrated towards the anode in borate buffer, pH 9.4. The OAD-sulforhodamines were amenable to TLC and were excellent substrates for enzymic transglycosylation and for glycosyl-hydrolase action. (c) 2006 Elsevier Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)44-54
Number of pages11
JournalCarbohydrate Research
Volume342
Issue number1
DOIs
Publication statusPublished - 15 Jan 2007

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