Promising Synthetic Antioxidants of Dimethyltin(IV) Formulations Derived From 4-Acylated Edaravone: Design, DFT Assisted Optimized Molecular Structure and Mechanistic Insights into SET Versus HAT Pathways for Antioxidant Activity.

Generation of some new complexes of dimethyltin(IV) of sterically congested 4-acylated amphiphilic edaravone having the general formula Me2SnLL' and Me2Sn(L')2 (where LH= , R = ─CH3, L(1)H; R = ─CH2CH3, L(2)H; R = ─C6H5, L(3)H; R = p-ClC6H4─, L(4)H and L' H= R'= p-OCH3C6H4─, L'(1)H; R'= p-CH3C6H4─, L'(2)H) has been accomplished. The newly generated complexes were characterized with the help of spectroscopic analysis [IR and NMR (1H, 13C and 119Sn)] assisted by DFT and HRMS studies. 119Sn NMR spectral data of some of these complexes revealed the existence of hexa-coordinated tin centres in these complexes. HRMS studies of some of the representative complexes suggested monomeric nature of these complexes. The optimized molecular structures and optimized energies of one representative ligand L'(1)H and the corresponding complexes, Me2SnL(4)L'(1) (Complex 4) and Me2Sn(L'(1))2 (Complex 9) were calculated using DFT-B3LYP functional in Spartan 20 computational modelling software. Some representative ligands and their corresponding dimethyltin(IV) complexes were tested for their antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Mechanistic insights into SET versus HAT pathways for antioxidant activity of dimethyltin(IV) formulations of 4-acylated edaravone derivatives have also been studied.