Ortho-palladated complexes with aromatic N-donor ligands, synthesis, characterization, molecular structures, antibacterial and anticancer activity

Ten newly synthesized ortho-palladated complexes of the type [PdCl(bhq)L] (1-10) (where bhp = benzo[H] quinolate, L = 2-aminobenzothiazole (2-abt), 2-amino-benzimidazole(2-abi), 2-aminothiazole(at), imidazole (im), 2-aminopyridine(2-apy), 2-amino-3-methylpyridine(2-ampy), 2-amino-5-chloropyridine(2-acpy), 3 -methyl-pyridine (3-mpy), 2-methylpyridine(2-mpy)or2-pyridinemethaneamine (2-pyma) have been prepared by bridge opening reaction of dimeric [PdCl(bhq)]2 with two equivalent of various aromatic N-donor ligands(L). The prepared complexes were characterized using IR, 1H n.m.r, mass spectroscopy, molar conductance, and X-ray crystallography. The results indicate that all complexes have a neutral square planar shape except complex (10) is ionic have electric conductance (40 mu s), then approved by the addition of AgNO3 solution to afford white precipitate of AgCl. The biological activity of the prepared complexes was examined against Pseudomonas aer-uginosa, Escherichia coli and staphylococcus aurous. The complexes showed good to moderate activity against the three pathogenic bacteria. Further more complex 4, displays the highest anti-bacterial activity than the other complexes. Some of the synthesized complexes were evaluated as anticancer, screening against A2780 and HCT-116 cell lines using the MTT colorimetric assay. The [Pd(bhq)Cl(im)] (4) complex exhibited significant cyto-toxicity against the HCT-116 and A2780 cell lines with IC50 values are 8.67 +/- 1.04 mu M and 6.32 +/- 0.86 mu M, respectively.

Automated summary

Ten newly synthesized ortho-palladated complexes were prepared by opening the bridge of dimeric [PdCl(bhq)]2 with various aromatic N-donor ligands. The complexes were characterized using various techniques and their antimicrobial and anticancer activities were evaluated. The complexes showed good antimicrobial activity against Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aurous. One of the complexes, [Pd(bhq)Cl(im)] (4), exhibited significant cytotoxicity against HCT-116 and A2780 cell lines.