New Antioxidant Triphenol-Derived Hydrazide-Hydrazone Thiazole: Formation and Analysis of Inclusion Complex with β-CD Using Experimental and Computational Approaches.

A new water-soluble not-colored antioxidant (Z)-N'-(4-(3,4-dihydroxyphenyl)-3-ethylthiazol-2(3H)-ylidene)-4-hydroxybenzohydrazide hydrochloride (DHTH) was obtained and characterized. The interaction between DHTH and β-CD was studied by experimental thermodynamic methods such as isothermal titration calorimetry (ITC) and H NMR spectroscopy and confirmed by in silico calculations. Thermodynamic data indicated that the inclusion process is driven by enthalpy, predominantly as a result of the guest-host hydrophobic interactions. H NMR measurements were applied to study the interaction with β-CD by changing the studied compound concentration in the solution. UV-vis titration and in vitro antiradical assay were performed, to study the antioxidant activity of DHTH, free and included in β-CD. A molecular docking study added supplementary insight to the experimental analyses regarding the binding conformation of the new polyphenolic compound to β-CD.