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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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13C NMR spectra of isomeric D-xylobioses
E. Petráková and P. Kováč
Institute of Chemistry, Slovak Academy of Sciences,
809 33 Bratislava
Abstract: 13C-NMR spectra of a series of isomeric D-xylobioses are compared with those of mono-O-methyl- and mono-O-benzyl-D-xylose. In terms of α effects, the benzyl group imitates β xylosylation better than does the Me group; neither of these 2 substituents satisfactorily imitates α xylosylation. The α effect of D-xylosylation is more pos. in β-(1→2)- and β-(1→3)-linked D-xylobioses than in their α-linked counterparts; these relations are reversed in (1→4)-linked substances. 13C-NMR spectra of mono-O-substituted derivs. of D-xylose (Me, benzyl, and α- and β-D-xylopyranosyl) show regularities, depending upon the site of substitution, concerning the principal anomer present in an equilibrated aq. soln. An alternative synthesis of 3-O-α- and 3-O-β-D-xylopyranosyl-D-xylose is also described. 4-O-Methyl-D-xylose was obtained for the 1st time in cryst. state.
Full paper in Portable Document Format: 354a551.pdf
Chemical Papers 35 (4) 551–566 (1981)
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