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Updated: Aug 22, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Conformational evaluation and detailed 1H and 13C NMR assignments of eremophilanolides
Eleuterio Burgueño-Tapia1, Luis R Hernández, Adriana Y Reséndiz-Villalobos
1Departamento de Química, Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, Av. Acueducto s/n, La Laguna Ticomán, México D.F., 07340 Mexico. eburgenio@acei.upibi.ipn.mx
Abstract:
Extensive application of 1D and 2D NMR methodology, combined with molecular modeling, allowed the complete 1H and 13C NMR assignments of eremophilanolides from Senecio toluccanus. Comparison of the experimental 1H, 1H coupling constant values with those generated employing a generalized Karplus-type relationship, using dihedral angles extracted from MMX and DFT calculations, revealed that the epoxidized eremophilanolides 1 and 2 show conformational rigidity at room temperature, whereas molecules 3-6, containing an isolated double bond, are conformationally mobile.
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