Examination of the molecular interactions of some antioxidant molecules by quantum chemical methods

The interaction of two important antioxidants uric acid and ascorbic acid molecules with water molecules is investigated by quantum chemical calculations. GAUSSIAN 09 software is used for modeling. Density fuctional theory at B3LYP level with 6-311++G(d,p) basis sets is used for modeling. The interaction is modeled by interacting uric acid and ascorbic acid with one water molecule one by one and one by five water molecules at the five active sides of the molecules. The optimized interacting structures are obtained and they are investigated by the IR vibrational analysis, bond lenght, angle and dihedral analysis, charge distribution and electric potential analysis and HOMO-LUMO analysis. The most stable tautomers of uric acid and isomers of ascorbic acid is determined for interaction.