This study analyzes the relationship that presents 11 aromatic compounds with heterocyclic Schiff bases and substituted in position meta and para with antioxidant activity, using the method UB3LYP/6-311G(d,p) within density functional theory.We determine the parameters: bond dissociation enthalpy (BDE), ionization potential (IP), protons dissociation enthalpy (PDE), affinity of protons (PA), electrons transfer enthalpy (ETE) and radical stabilization energy (RSE), all in gaseous phase. The results show that electrodonorssubstituents increases BDE when they are in position para, IP in position meta and para and ETE in position para. In addition, the electroatractors cause an increase in PDE and PA at position meta and para.

This paper discusses global descriptors such as hardness, electronegativity, nucleofilia and chemical potential and local reactivity indexes. We use the method of the density functional (DFT) to a level of calculation B3LYP/6-31G. With local reactivity indexes analyzed the nucleophile/electrophile character by the effect of substituents on the system 1,2-benzoquinone. With global descriptors of reactivity, we obtained acceptable correlations as well as the effect of substituents on the Uv-vis spectrum groups.