Conformational insights and vibrational study of a promising anticancer agent: the role of the ligand in Pd(II)-amine complexes

A conformational and vibrational analysis of an antiproliferative spermine-based dinuclear Pd(II) complex (Pd-2-Spm) is reported. Density functional theory coupled to all-electron basis sets was used to perform quantum mechanical calculations aimed at determining the strategy best suited for accurately representing this molecule and achieving an optimal accordance with the experimental data. The structural parameters and the vibrational frequencies predicted by the calculations are compared with the corresponding experimental data. The results support a relationship between the strength of the metal-ligand bonds and the antitumor activity of the compound.