Theoretical study of the hydrogen abstraction from vitamin-E analogues. The usefulness of DFT descriptors.
The activation and reaction energies governing hydrogen atom transfer between α-tocopherol analogues and methylperoxyl radical were determined using the B3LYP/6-311++G(d,p) method. An a priori qualitative estimation of the charge transfer involved in the formation process of the two-fragment reaction between α-tocopherol-like molecules and the methylperoxyl radical was used as a predictive tool to determine antioxidant activity. Consistency between the energetic data and reactivity criterion was nicely reached indicating that the electronic nature of the substituents in the heterocyclic ring in α-tocopherol-like molecules strongly influences the activation and reaction energies.
Gutiérrez-Oliva
Soledad
S
QTC, Departamento de Química-Física, Facultad de Química, Pontificia Universidad Católica de Chile, Casilla 306, Correo 22, Santiago, Chile. msg@uc.cl
D000975:Antioxidants / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D008958:Models, Molecular; D013329:Structure-Activity Relationship; D024502:alpha-Tocopherol / Q000031:analogs & derivatives / Q000737:chemistry*
D000975:Antioxidants; D006859:Hydrogen; D024502:alpha-Tocopherol