Synthesis, Characterization,in vivoAntimalarial Studies and Geometry Optimization of Lumefantrine/Artemether Mixed Ligand Complexes

Abstract

Fe(III). Zn(II), Cu(II), Cd(II), Ni(II) and Co(II) complexes of Artemether/Lumefantrine were synthesized. The yield, colour, melting point and solubility of the complexes and antimalarial drug were determined. The complexes were stable, non hygroscopic solids with high melting points. The electronic spectra showed that all the complexes and antimalarial drug absorbed in ultraviolet region because of the presence of C=Cchromophore and ligand to metal charge transfer (LMCT). The infrared spectra of the complexes showed evidence of coordination through the lone pair electrons of nitrogen atom (C-N) stretch in Lumefantrine, lone pair of electrons of oxygen atom (R-O-R) stretch and S=O functional group. In most of he complexes, Artemether behave as a tridentate ligand while Lumefantrine behave as a monodentate ligand. From the in vivo antimalarial studies, it was evident that the addition of the metal to the mixed ligand did not impede/hinder the therapeutic value of the mixed ligand. Thus, it was deduced that Ni-artemether/lumefantrine and Cu-artemether/lumefantrine complexes were more effective than artermether-lumefantrine alone against strains of Plasmodium Berghei. Geometry optimization of artemether/lumefantrine complexes were performed using ArgusLab 4.0.1 software. The minimum potential energy was calculated by geometry convergence function using ArgusLab software. The most feasible position for the complexes to inhibit angiogenesis and modulate host immune function was found to be in the range 591.5027 -727.0168 Kcal/mol.