Synthesis and anticancer property of two Sm(III) compounds based on tetrazole ligands

Abstract Developing new drugs for the treatment of cancer is of great significance. Coordination compounds based on tetrazole-carboxylates are one of the most potential candidates for the treatment of cancer. Two metallic compounds coordinated and controlled by bifunctional tetrazolate-carboxylate H3L1 and L2 ligands [H3L1= N,N-di(2’- carboxymethyl terazole-5-yl) amine and L2 = 2-(5-pyridin-2-yl-tetrazol-2-yl)malonic acid diethyl ester] have been synthesized and characterized by single crystal X-ray diffraction analysis. The [Sm(L1)(H2O)3]·4H2O (1) displayed a 2-D network while [Sm(L2)3(OH)3] (2) with a mononuclear cluster structure. The effect of the main ligands in the two compounds on ablation of cancer cells were explored. Nanoparticles (NPs) of the two compounds can be prepared by PEG-2000 (Polyethylene glycol-2000) co-precipitation method. In vitro MTT assay on HeLa cells showed that 2 NPs with a lower IC50 (half maximal inhibitory concentration) of only 1.3 μM is lower than that of 1 NPs (1.6 μM), indicating that the cytotoxicity of compound 2 NPs is superior to that of compound 1 NPs. The results showed that [Sm(L1)(H2O)3]·4H2O (1) and [Sm(L2)3(OH)3] (2) NPs were capable of inhibiting cell proliferation in vitro and may be a potential candidate against cancer.