Promising Synthetic Antioxidants of Dimethyltin(IV) Formulations Derived From 4-Acylated Edaravone: Design, DFT...

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.