Synthesis, characterization, lipoxygenase, and tyrosinase inhibitory activities of non- cytotoxic titanium(III) and (IV) hydrazide complexes

Ti(III) and (IV) hydrazide complexes were synthesized, characterized, and screened for their tyrosinase and lipoxygenase inhibitory and cytotoxic activities. The geometry of Ti(III) hydrazide complexes is tentatively assigned as octahedral. Magnetic moments were found around 1.7 B.M. and electronic spectral transition in the range of 495-518 nm. Evaluation of Ti(IV) and Ti(III) hydrazide complexes for tyrosinase and lipoxygenase inhibitory activities revealed varying inhibition potential. Hydrazide ligands were inactive against tyrosinase, while significant activity was observed against lipoxygenase (LOX). Good to moderate inhibition activity was observed by Ti(IV) and Ti(III) hydrazide complexes against both enzymes. At the same time, promising results were obtained for Ti(IV) hydrazide complexes against tyrosinase enzymes suggesting their broad application as tyrosinase inhibitors. Complex 4d possess negative inhibition, thus behaving as a tyrosinase activator. The docking results showed a good correlation between complex experimental activities and binding energies. Cytotoxic investigation revealed the non-toxicity of complexes against normal cells. KEY WORDS: Titanium(III) and titanium(IV) hydrazide complex, Tyrosinase, Lipoxygenase, Inhibition, Molecular docking, Cytotoxicity Bull. Chem. Soc. Ethiop. 2023, 37(2), 315-333. DOI: https://dx.doi.org/10.4314/bcse.v37i2.6