Spectroscopic investigation, DFT calculations and cytotoxic activity of a 1-amino-1,3-dihydrospiro[imidazoline-4,2-indene]-2,5-dione and its platinum and palladium complexes

1-Amino-1,3-dihydrospiro[imidazoline-4,2-indene]-2,5-dione and its Pt(II) and Pd(II) complexes were synthesized. The structures of the compounds were characterized by elemental analysis, IR, H-1 and C-13 NMR spectra. The analyses indicated that the complexes have general formula cis-[ML2Cl2] and the ligand coordinatedvia nitrogen atom from NH2 group. The molecular structure of the ligand and its Pt(II) and Pd(II) complexes were studied computationally by hybrid DFT calculations. Theoretical analysis of the complexes confirmed that the cis-isomers are more stable than trans and complexes exhibit square planar coordination. The cytotoxic activity of the new ligand and its complexes was determined in vitro by MTT assay against K-562 and HL-60 human tumor cell lines. The IC50 values of the tested compounds showed that the Pt(II) complex with 1-amino-1,3-dihydrospiro[imidazoline-4,2-indene]-2,5-dione has higher cytotoxic activity than the palladium(II) complex with the same ligand, which confirmed that platinum complexes show higher activity than the corresponding palladium complexes.