Oxidovanadium(V) Schiff Base Complexes Derived from Chiral 3-amino-1,2-propanediol Enantiomers: Synthesis, Spectroscopic Studies, Catalytic and Biological Activity.

Oxidovanadium(V) complexes, [(+)VOL 1-5 ] and [(-)VOL 1-5 ] , with chiral tetradentate Schiff bases, which are products of monocondensation of S (‒)-3-amino-1,2-propanediol or R (+)-3-amino-1,2-propanediol with salicylaldehyde derivatives, have been synthesized. Different spectroscopic methods, viz. 1 H and 51 V NMR, IR, UV-Vis, and circular dichroism, as well as elemental analysis, have been used for their detailed characterization. Furthermore, the epoxidation of styrene, cyclohexene, and two monoterpenes, S (‒)-limonene and (‒)-α-pinene, using two oxidants, aqueous 30% H 2 O 2 or tert -butyl hydroperoxide (TBHP) in decane, has been studied with catalytic amounts of all complexes. Finally, biological cytotoxicity studies have also been performed with these oxidovanadium(V) compounds for comparison with cis -dioxidomolybdenum(VI) Schiff base complexes with the same chiral ligands, as well as to determine the cytoprotection against the oxidative damage caused by 30% H 2 O 2 in the HT-22 hippocampal neuronal cells in the range of their 10-100 μM concentration.