Theoretical Investigation of Antioxidant Activity of Hydroxy-Quinoline Derivatives and their Delivery Via Boron Nitride Nanocage in Gas Phase and Solvent

Abstract

The antioxidant activity of hydroxy-quinoline derivatives was studied in gas phase and solvent. Results indicate that substituents in hydroxy-quinoline decrease the bond dissociation enthalpy and ionization potential values and thus increase the antioxidant activity of hydroxy-quinoline. Results also show that NHMe hydroxy-quinoline has the highest antioxidant activity. The ability and potential of boron nitride (B 36 N 36 ) nanocage in the delivery of hydroxy-quinoline derivatives via DFT method was studied. Results show that adsorption of hydroxy-quinoline derivatives on the surface of B 36 N 36 nanocage was exothermic. There were linear dependencies between antioxidant parameters and adsorption energy (E ad ) values of hydroxyquinoline derivatives. We thus propose to synthesize novel hydroxy-quinoline derivatives with higher antioxidant activity.Keywords: BN nanocage, DFT and solvent, drug delivery, hydroxy-quinoline.IT is well known that hydroxy-quinoline (ArOH) derivatives have high antioxidant activity and protect us against diseases 1-4 . Hydroxy-quinoline derivatives deactivate free radicals (ROO  ) by hydrogen atom transfer (HAT) and single-electron transfer followed by proton transfer (SET-PT) mechanisms (eqs (1)- (3))Bond dissociation enthalpy (BDE) and ionization potential (IP) represent enthalpies of the HAT and SET-PT mechanisms respectively 5-9 . The enthalpy of X and the BDE and IP parameters were calculated as follows H(X) = E 0 + ZPE + H trans + H rot + H vib + RT.Here H is enthalpy and ZPE is zero point energy. In the present study, the antioxidant activity of hydroxyquinoline derivatives was investigated using the HAT and SPLET mechanisms. The effects of solvent and substituents on the antioxidant activity of hydroxy-quinoline derivatives were studied (Figure 1). The results obtained will help identify novel hydroxy-quinoline derivatives with higher antioxidant activity. In recent years nanocages have been used for the delivery of important drugs. Fullerenes have several conjugated double bonds; they can attach to radical species, and thus exhibit high biological activity [10][11][12][13] . Boron nitride (BN) nanocages have bio-compatibility properties and biomedical applications; thus they have been used in the delivery of antioxidants. The interactions of BN nanocages with various drugs showed that the nanocages have suitable structures to transfer the useful antioxidant drugs [10][11][12][13] . The ability and potential of BN nanocages (B 36 N 36 ) to transfer hydroxy-quinoline derivatives were studied (Figure 2). The adsorption energy is calculated as followswhere E (B 36 N 36 nanocage) is the energy of the B 36 N 36 nanocage, E (hydroxy-quinoline) the energy of hydroxyquinoline, and E BSSE is the energy of basis set superposition error calculated by counterpoise correction method. The structures of hydroxy-quinoline derivatives and their radical and cation radical conformers were geometry-optimized by DFT/B3LYP method. The structures of the B 36 N 36 nanocage and their complexes with...

Ability ofB12N12fullerene like nano‐cage for sensing and improving the antioxidant activity of juglone and its derivative: Density functional theory investigation

“…Moreover, BN fullerene like cages have been found to improve the antioxidant activity of phenolic compounds through their adsorption on the external surface of the former. In this perspective [18], showed that B 36 N 36 can efficiently improve the antioxidant activity as well as the delivery of hydroxyquinoline derivatives. Analysis of the antioxidative mechanisms of a complex formed from the adsorption of apigenin on B 12 N 12 surface also revealed the improvement of radical scavenging activity of apigenin by B 12 N 12 [19].…”