The complexes of the types Ln(HN) 3.nH 2O [where Ln = Ce, La, Nd; HN = Niffcoumar] have been synthesized by reaction of Niffcoumar sodium salt and the appropriate lanthanide nitrates. The solid complexes have been characterized and identified on the basis of elemental analysis, conductivities, IR- and 1H-NMR-spectroscopy. We suppose that the lacton- and keto-carbonyl oxygen atoms of Niffcoumar are bonded to the metal ion probably as a bidentate ligand. The experimental data obtained by MTT-assay show that all tested compounds manifest a similar low cytotoxic activity on lymphoma derived P3HR1 cells (20% maximum cell growth inhibition). The complexes of La and Nd have been shown to be more cytotoxic than the Ce complex against K-562 cells (about 75% maximal growth inhibition). Low to moderate cytotoxic activity has been established for the complexes of La and Ce on TPH-1 cells (25% maximum inhibition of cell growth). Our data indicate that the lanthanide complexes may have some antitumour potential which depends on the metal and the cell line used.
Read full abstract