Conformational Analysis of Profisetinidin Dimers

  • Carin A. Heifer
  • Wayne L. Mattice
Part of the Basic Life Sciences book series (BLSC, volume 59)

Abstract

Steady-state and time-resolved fluorescence measurements show that profisetinidin dimers with a (4α → 8) interflavan bond exist as two rotamers in an approximately equal proportion. The 2,3-trans profisetinidin dimers with a 4β interflavan bond also exist as two rotamers, however, a higher fraction of one of the two rotamers is present. Molecular modeling with the Sybyl 5.41 force field shows two low energy conformations when rotating 360° around the interflavan bond defined by C3, C4, D8, D7. In fisetinidol-(4β → 8)-epicatechin, there is a high energy barrier at ϕ = 180° due to steric interference of the C-3 hydroxyl with the F-ring pyran oxygen. Lowest energy states are at ϕ = 90° and 240°. The energy barrier at ϕ = 180° is much lower for fisetinidol-(4α0 → 8)-epicatechin than observed in the 4β-linked isomer. A molecular dynamics trajectory was computed using Sybyl 5.41 for fisetinidol-(4β → 8)-epicatechin to study rotation about the interflavan bond. At 500 oK, rotation at the interflavan bond is slow with less than one rotation occurring in 50 ps.

Keywords

Phenol Hydroxyl Oligomer Pyran Poly Phenol 

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Copyright information

© Springer Science+Business Media New York 1992

Authors and Affiliations

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

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