Anomalous Zemplén deacylation reactions of α- and β-D-mannopyranoside derivatives

Károly Ágoston, András Dobó, János Rákó, János Kerékgyártó, Zoltán Szurmai

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17 Citations (Scopus)

Abstract

Reaction of mono-, di-, and trisaccharide derivatives of methyl β-D- and octyl β-D-mannopyranosides bearing ester groups at isolated and non-isolated positions on the same molecule, under Zemplén conditions (catalytic amount of sodium methoxide in methanol) gave partially deacylated compounds, in which the O-acyl groups were retained at isolated sites. In the case of one disaccharide, all the benzoyl groups remained intact at the reducing end, while all the acetyl functions were removable from the nonreducing end. In another case, both isolated ester groups at positions 2 and 4 were retained at the reducing end. The isolated 2-O-acyl groups on methyl α-D-mannopyranoside compounds were more labile than on the corresponding β-mannosides under the same conditions. The mechanism of the reaction may be different for ester groups at isolated or non-isolated positions. In the latter case, acyl migration may take place and carry acyl groups into a less hindered position.

Original languageEnglish
Pages (from-to)183-190
Number of pages8
JournalCarbohydrate Research
Volume330
Issue number2
DOIs
Publication statusPublished - Jan 30 2001

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Keywords

  • Anomalous Zemplén deacylation
  • Mannosides
  • Temporary ester groups

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Organic Chemistry

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