Antiradical activity of naringin and its Fe(III) and Cu(II) complex

YONE MELISA RENFIGE RODRIGUEZ; MARIELA FINETTI; GUSTAVO CÉLIZ

Posadas, Misiones

Simposio; 6th Latin American Symposium on Coordination and Organometallic (SILQOM6); 2018

Comité Organizador del SILQCOM6

Flavonoids exert their antiradical activity directly by scavenge free radicals or indirectly by chelating metals that generates radicals. It has been reported that the direct antiradical capacity of flavonoids is increased if they are forming coordination complex. In this work, we evaluated the antiradical activity of naringin and how it is affected with the formation of Cu and Fe complexes. We also investigated how these metals influence the antiradical capacity of naringin.First Cu(II)-Nar and Fe(III)-Nar were synthesized. Then, the antiradical activities of the compounds against DPPH were determined. Calculi were performed using DFT methods. The complex structures were optimized starting from the obtained by X-ray diffraction for the Cu(II)-naringenin complex.The complexes were synthesized at gram scale with a high purity. Cu(II)-Nar and Fe(III)-Nar had more antiradical activity against DPPH than Nar. For Nar and its complexes the enthalpy bond, electron transfer enthalpy (ETE), proton affinity (PA), proton dissociation enthalpy (PDE), ionization potential (IP) and electron affinity (EA) were determined. The results indicate that H4´ is the H-donor with the highest radical scavenging activity in a direct H atom transfer mechanism (HAT). For this mechanism, no increase in activity is predicted by calculus when NAR is forming the complexes. Probably could take part intermolecular rather than intramolecular reasons.