Skip to Main Content
Crystal structure, conformational analysis, and molecular dynamics of tetra-0-methyl-(+)-catechinAuthor(s): Frank R. Fronczek; Richard W. Hemingway; G. Wayne McGraw; Jan P. Steynberg; Carin A. Helfer; Wayne L. Mattice
Source: Biopolymers 33(275-282
Publication Series: Miscellaneous Publication
PDF: View PDF (1.8 MB)
DescriptionThe structure of tetra-O-methyl-(+)-catechin has been determined in the crystalline state. Two independent molecules, denoted structure A and structure B, exist in the unit cell. Crystals are triclinic, space group P1, a=4.8125(2) Ǻ, b=12.9148(8) Ǻ, c=13.8862(11) Ǻ, α=86.962(6)°, β=89.120(5)°, γ=88.044(5)°, Ζ=2, De=1.336 g cm-3, R=0.033 for 6830 observations. The heterocyclic rings of the crystal structures are compared to previous results for 8-bromotetra-O-methyl-(+)-catechin, penta-O-acetyl-(+)-catechin, and (-)-epicatechin. One of the two molecules has a heterocyclic ring conformation similar to that observed previously for (-)-epicatechin, and the other has a heterocyclic ring conformation similar to one predicted earlier in a theoretical analysis of dimera of (+)-catechin and (-)-epicatechin. Both structure A and structure B in the crystal have heterocyclic ring conformations that place the dimethoxyphenyl substituent at C(2) in the equatorial position. However. this heterocyclic ring conformation does not explain the proton nmr coupling constant measured in solution. Molecular dynamics simulations show an equatorial- axial interconversion of the heterocyclic ring, which can explain the nmr results.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationFronczek, Frank R.; Hemingway, Richard W.; McGraw, G. Wayne; Steynberg, Jan P.; Helfer, Carin A.; Mattice, Wayne L. 1993. Crystal structure, conformational analysis, and molecular dynamics of tetra-0-methyl-(+)-catechin. Biopolymers 33(275-282
- Dipole moment, solution, and solid state structure (-)-epicatechin, a monomer unit of procyanidin polymers
- Preference for occupany of axial positions by substituents bonded to the heterocyclic ring in penta-O-acetyl-(+)-catechin in the crystalline state
- Conformational isomerism of phenolic procyanidins: preferred conformations in organic solvents and water
XML: View XML