Iron(III), gold(III), platinum(IV) and palladium(II) trimethoprim drug complexes: synthesis, spectroscopic, morphological and anticancer assessments

Abstract

Iron(III), gold(III), platinum(IV) and palladium(II) complexes of trimethoprim (TMP) drug were synthesized and well characterized using elemental analysis, conductance measurements, (UV-Vis, FTIR, 1HNMR and X-ray powder diffraction) spectroscopy. The Au(III), Pt(IV) and Pd(II) complexes have a four coordinate geometry comprising one molecules of the TMP drug and two coordinated chloride ions, while, iron(III) complex has an octahedral geometry containing one TMP, three chloride and one coordinated water molecules. The TMP drug acts as a bi-dentate chelate towards the metal ions through the nitrogen atoms of the two amino groups attached with pyrimidine ring, this was confirmed by spectroscopic analyses with the molecular formulas [Fe(TMP)Cl3(H2O)].4H2O, [Au(TMP)Cl2]Cl2H2O, [Pt(TMP)Cl2]Cl22H2O and [Pd(TMP)Cl2]. The transmission electron microscopy (TEM) and XRD analyses deduced that the gold(III) complex has a nano-scale range at ~ 10 nm. The [Au(TMP)Cl2]Cl2H2O complex was screened for its cytotoxicity evaluation against hepatocellular carcinoma (HepG2) and colon carcinoma (HCT-116) cell lines. It is showed that the IC50 of gold(III) complex are 7.46 µg/mL and 9.30 µg/mL against HepG2 and HCT-116 cancer cell lines, respectively.