Synthesis, spectroscopic, DFT, cytotoxicity and antimicrobial activity of Pd(II) and Pt(II) complexes of N,N-chelated benzimidazole derivatives

•Structural studies of cis-platin analogs Pd(II) and Pt(II) complexes were reported.•Cytotoxicity is affected by type of the aniline substituent.•Electronic transitions were assigned by the aid of TD-DFT calculations.•Electronic arrangement, hybridization and bonding properties were discussed.

New cis-platin analogs PdII and PtII complexes of (1H-benzimidazol-2-ylmethyl)-N-(4-chloro-phenyl)-amine (LCl) and (1H-benzimidazol-2-ylmethyl)-N-(4-iodo-phenyl)-amine (LI) were prepared as potential antitumor compounds, characterized (elemental analysis, TG/DTA, FT IR, 1H NMR, MS, UV–Vis. and conductance measurements) and tested for their cytotoxic activities against MCF7, HCT and HEPG2. The antibacterial activity was tested on against Staphylococcus aureus, Bacillus subtilis, Streptococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Neisseria gonorrhea. The effect of the aniline substituent on the toxicity was discussed. The experimental studies were complemented by quantum chemical calculations. TD-DFT calculations were carried out to understand the electronic structure and to explain the related experimental findings. Natural bond orbital analysis was performed to provide details about the electronic arrangement, type of hybridization and the nature of bonding.

Graphical abstractNew cis-platin analogs Pd(II) and Pt(II) complexes of benzimidazole derivatives were synthesized, characterized and tested for their antitumor activities. Geometry optimization, molecular electrostatic potential maps and the description of frontiers MO’s were carried out.Figure optionsDownload full-size imageDownload as PowerPoint slide