Investigations towards the Synthesis of 5-Amino-l-lyxofuranosides and 4-Amino-lyxopyranosides and NMR Analysis

Abstract

Abstract The reactivity of trifluoromethanesulfonyl esters derived from l-lyxofuranosides and l-lyxopyranosides was investigated with various 5-aminopyrimidines as nucleophiles with the expectation to synthesize N-substituted 5-amino-ribosugars. The lyxopyranoside forms were found to be unreactive, while the lyxofuranoside forms were found to be reactive with 5-aminopyrimidines, yielding novel N-substituted 5-amino-lyxofuranosides. We report on the synthesis of these novel N-substituted lyxofuranosides and the systematic analyses of NMR data that demonstrate trends within each series: furano-, pyrano-, β- and α- anomers of l-lyxose and β-d-ribopyranoside forms. The data call for caution when identifying these monosaccharides in isomeric mixtures.

Keywords

• l-lyxofuranoses
• l-lyxopyranoses
• d-ribopyranoses
• conformation analysis
• heterocycles
• nmr spectroscopy