Bioactivity of novel transition metal complexes of N'-[(4-methoxy)thiobenzoyl]benzoic acid hydrazide.

ABSTRACT

Cu(II), Fe(III), and Mn(II) complexes of a novel ligand N'-[(4-methoxy)thiobenzoyl]benzoic acid hydrazide (H(2)mtbh) have been synthesized and characterized by elemental analyses, IR, UV-vis, NMR, mass, EPR and Mössbauer spectroscopy. The results suggest a square planar structure for [Cu(Hmtbh)Cl] and [Cu(mtbh)] whereas an octahedral structure for [Mn(Hmtbh)(2)] and [Fe(Hmtbh)(mtbh)]. Mn(II) and Fe(III) complexes were found to inhibit proliferation of HT29 cells. [Mn(Hmtbh)(2)] and [Fe(Hmtbh)(mtbh)] inhibited proliferation of HT29 cells with half maximal inhibition (IC(50)) of 8.15+/-0.87 and 68.1+/-4.8 microM, respectively, whereas H(2)mtbh showed growth inhibition with IC(50) of 90.9+/-7.8 microM and were able to inhibit NMT activity in vitro. Mn(II) and Fe(III) complexes inhibited NMT activity in a dose dependent manner with IC(50) values of 20+/-2.2 and 60+/-7.2 microM, respectively, whereas ligand (H(2)mtbh) displayed IC(50) of 3.2+/-0.5 mM.