Synthesis, characterization and biological activity of complexes of lanthanum(III) with 2-(1′-phenyl- 2′-carboxyl-3′-aza-n-butyl)-1,10-phenanthroline and 2-(1′-p-phenol-2′-carboxyl-3′-aza-n-butyl)-1,10-phenanthroline Original Research Article

Two novel ligands 2-(1′-phenyl-2′-carboxyl-3′-aza-n-butyl)-1,10-phenanthroline (L1) and 2-(1′-p-phenol-2′-carboxyl-3′-aza-butyl)-1,10-phenanthroline (L2), and their La(III) complexes of La(III)L1, La(III)(L1)2, La(III)L2, and La(III)(L2)2, were synthesized and characterized by 1H NMR, elemental analysis, IR, thermal analysis and conductance measurement. All complexes have been assayed for anticancer activity in vitro against HL-60 (human leukocytoma) cells, PC-3MIE8 (human prostate carcinoma) cells, BGC-823 (human stomach carcinoma) cells, MDA-MB-435 (human galactophore carcinoma) cells, Bel-7402 (human liver carcinoma) cells, and HeLa (human cervix carcinoma) cells. Results showed that the two complexes La(III)L1 and La(III)(L1)2 exhibited good cytotoxic activity against different cell lines in general; and La(III)(L1)2 is more effective than cisplatin against all six cell lines. DNA-binding studies indicated that, besides the intercalation, the complexes bind to DNA by the other interaction(s).