Synthesis, characterization, and anticancer activities of lipophilic pyridinecarboxaldimine platinum(II) complexes

We have prepared eleven pyridinecarboxaldimines (N-N'R) from the condensation of 2-pyridinecarboxaldehyde and the corresponding lipophilic primary amines. Addition of these ligands to [PtCl2(eta(2)-coe)](2) (coe = cis-cyclooctene) gave complexes of the type cis-PtCl2(N-N'R) (2a-k) in moderate to high yields. The molecular structure of the N-butylphenyl derivative (2h) has been confirmed by an X-ray diffraction study. Crystals of 2h were monoclinic with a = 8.5414(9)angstrom, b = 11.6774(12)angstrom, c = 16.1235(16)angstrom, beta = 92.7610(10)degrees in the space group P2(1)/c. All platinum complexes were examined for their in vitro cytotoxic properties against two human glioblastoma multiforme cell lines LN18 and LN405. The DNA binding properties of one of the most cytotoxic compounds was compared with that of cisplatin, but no effect was observed under the conditions tested. (C) 2015 Elsevier Ltd. All rights reserved.