Synthesis, Characterization, Stability and Cytotoxic Evaluation of Novel Titanium(IV) Complexes of 8-Hydroxyquinoline and 2-Hydroxy-N-phenylbenzylamine Derivatives

Abstract

A new class of moisture stable heteroleptic titanium(IV) complexes, synthesized from 8-hydroxyquinoline of the type [(Q)2Ti(2-O-5-X-C6H3CH2NC6H4R] (3a-j), was prepared by reacting the antecedent molecule [(Q2)Ti(OiPr)2] (2) with various 2-hydroxy-N-phenyl-benzylamine analogues in 1:1 molar ratios in dry toluene (where, HQ = 8-hydroxyquinoline; iPr = isopropyl; R = H, 4-CH3, 4-OCH3, 2-Cl, 4-Cl, 2-Br, 4-Br; X= H, Br). Moisture sensitive study disclosed that these new metal complexes were unreacted for 72 h. Mass spectral data were employed for proving the mono-nuclearity of the new derivatives. Thermal decomposition pattern of the new derivatives was explained by thermogravimetric analyses. Elemental analyses data are in concordance with their expected values. The hexa-coordinated way of titanium-ligand linkage is further proved through NMR, FTIR, and UV-visible spectral studies. The cytotoxic efficiency of new complexes was tested against MDA-MB-231 human breast carcinoma cell line. Complex 3a exhibited the highest cytotoxic potential of 0.039 μM in comparison to all its analogues of this series by employing cisplatin as the standard