TY - JOUR
T1 - DFT, solution, and crystal conformation of eremophilanolides
AU - Burgueño-Tapia, Eleuterio
AU - Hernández-Carlos, Beatriz
AU - Joseph-Nathan, Pedro
N1 - Funding Information:
Financial support from SIP-IPN and CONACYT is acknowledged. We thank M. C. Ernestina Cedillo Portugal (Universidad Autónoma de Chapingo, Chapingo, Mexico) for the identification of the plant material.
PY - 2006/12/15
Y1 - 2006/12/15
N2 - The minimum energy conformation of five eremophilanolides (1-5) from the tubercles of Psacalium paucicapitatum was calculated using density functional theory (DFT) at the B3LYP/6-31G* level. Comparison of the experimental 1H-1H coupling constant values of 1-5 with those generated employing a generalized Karplus-type relationship using dihedral angles extracted from the DFT calculation and from the crystal structures for 1 and 3-5 shows good agreement. The A ring of 1-5 adopts an almost perfect chair conformation with the Me-14 group in an axial position and the Me-15 in an equatorial position.
AB - The minimum energy conformation of five eremophilanolides (1-5) from the tubercles of Psacalium paucicapitatum was calculated using density functional theory (DFT) at the B3LYP/6-31G* level. Comparison of the experimental 1H-1H coupling constant values of 1-5 with those generated employing a generalized Karplus-type relationship using dihedral angles extracted from the DFT calculation and from the crystal structures for 1 and 3-5 shows good agreement. The A ring of 1-5 adopts an almost perfect chair conformation with the Me-14 group in an axial position and the Me-15 in an equatorial position.
KW - C NMR
KW - Crystal structure
KW - DFT calculations
KW - Eremophilanolides
KW - H NMR
KW - Psacalium paucicapitatum
UR - http://www.scopus.com/inward/record.url?scp=33751297243&partnerID=8YFLogxK
U2 - 10.1016/j.molstruc.2006.04.028
DO - 10.1016/j.molstruc.2006.04.028
M3 - Artículo
SN - 0022-2860
VL - 825
SP - 115
EP - 123
JO - Journal of Molecular Structure
JF - Journal of Molecular Structure
IS - 1-3
ER -