Half-sandwich ruthenium(II)(η6-p-cymene) complexes: Syntheses, characterization, transfer hydrogenation reactions, antioxidant and enzyme inhibitory activities

Abstract

The five new Ru(II)(η6-p-cymene) complexes (1-5) were successfully synthesized, characterized by FT-IR, elemental analysis, electronic spectra, proton and carbon NMR, mass spectra and thermal analysis, and applied in the transfer hydrogenation of ketones. In addition, enzyme inhibitory and antioxidant activities of novel Ru(II)(η6-p-cymene) complexes were evaluated using several in vitro methods. The stabilities of complexes were checked by UV-Vis. spectroscopy. The results of enzyme assays showed that novel Ru(II)(η6-p-cymene) complexes had effective inhibitions against the tyrosinase and pancreatic lipase enzymes. The IC50 values of five different (1-5) for tyrosinase were found as 34.65±1.2 µM, 31.51±1.7 µM, 49.50±3.1 µM, 19.25±0.9 µM, and 63.01±3.3 µM, respectively. Furthermore, ABTS, CUPRAC, DPPH, and FRAP in vitro methods were utilized to assess the antioxidant capabilities of the compounds. The powerful antioxidant potentials of the synthesized compounds were detected compared to the standards, such as BHA, BHT, ascorbic acid, and α-tocopherol. This study provides a valuable potential of the novel Ru(II)(η6-p-cymene) complexes for pharmacological studies with further analytical experiments to explore their full properties.