Structure-Activity Relationship Study on the Antioxidant Effects of 2-Phenylnaphthalene

With the aid of density functional theory, the antioxidant properties of resveratrol and its six 2-phenyl naphthalene derivative compounds, as well as their internal influencing factors, were comprehensively analyzed. It was found that the antioxidant activity of 2-phenyl naphthalene compounds is remarkably influenced by the position of the phenol hydroxyl group. The antioxidant activity of compound molecules with a dihydroxy structure is augmented by intramolecular hydrogen bonding. In contrast, the antioxidant activity of the hydroxyl group on the naphthalene ring surpasses that on the benzene ring. This is attributed to the fact that the conjugation of the naphthalene ring is more pronounced, thereby facilitating a higher stability of free radicals. In summary, the higher the antioxidant activity of a given site, the greater the charge on the H atom of the phenolic hydroxyl group and the lower the energy of the hydrogen extraction reaction at that site. Moreover, the stronger the solvent polarity and intermolecular hydrogen bond are, the stronger the antioxidant activity is.