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Conformational Analysis of Oligomeric Proanthocyanidins

  • Wayne L. Mattice

Abstract

The conformational behavior of polymers of 2,3-trans- and 2,3-cis-flavan3-ols [(+)-catechin and (−)-epicatechin] depends on the population of dihedral angles at the interflavan bond and the conformation of the heterocyclic rings. The behavior of the heterocyclic rings can be determined by study of the monomers and dimers. The results obtained from x-ray diffraction and MM2 calculations are reviewed here. Conformations at the interflavan bond are studied by MM2 calculations, high resolution 1H-NMR, and time-resolved fluorescence. The implications of these results are that 4β → 8 linked polymers are random coils with dimensions somewhat smaller than those of unperturbed polystyrene chains of the same molecular weight. The dimensions of polymers with 4β → 6 links are not much different.

Keywords

Dihedral Angle Heterocyclic Ring Conformational Energy Fuse Ring System Monodisperse Sample 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Wayne L. Mattice
    • 1
  1. 1.Institute of Polymer ScienceThe University of AkronAkronUSA

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