C 2 ,N-dimethylbenzylamine cyclopalladated compounds: evaluation of cytotoxic, mutagenic and antitubercular activities

Abstract

Mono- and binuclear cyclometallated Pd(II) compounds containing C,N-chelating dimethylbenzylamine (Hdmba) have been synthesized aiming at investigating their mutagenic properties (Ames test) and cytotoxic activity toward murine tumor cell lines and Mycobacterium tuberculosis. By reactions of [Pd(C 2 ,N-dmba)(μ-X)]2 {X = Br (1), I (2)} with thiourea (tu), in the 1:2 molar ratio, the mononuclear compounds [Pd(C 2 ,N-dmba)(X)(tu)] {X = Br (3), I (4)} were readily obtained. The new compound 4 was characterized by elemental analyses, infrared (IR) and 1H- and 13C{1H}-NMR spectroscopies. The cytotoxicity assessment of the cyclopalladated compounds 1–4 revealed that the iodo-derivative 4 was the most active toward murine mammary adenocarcinoma (LM3) cells, even more effective than cisplatin. The cyclometallated compounds 1–4 did not demonstrate mutagenic potential according to Ames test results. Compound 4 was only moderately active (MIC = 60 μg mL−1) against M. tuberculosis. Mono- and binuclear cyclopalladated compounds have been synthesized. These complexes displayed cytotoxic levels toward murine mammary adenocarcinoma cells comparable to cisplatin. Cyclopalladated compounds were non-mutagenic in the Ames test, contrary to cisplatin and its analogues.