Cadmium complexes and cocrystals of indium complexes of benzothiazole derivatives and anticancer activities of the cadmium complexes

Cadmium and indium complexes [Cd(L1)(O2CCH3)2(H2O)] (1) [Cd(L2)2(O2CCH3)2(H2O)] (2), [L1In(H2O)Cl3]·L1 (3) and [L1In(MeOH)Cl3]·L1 (4) (where L1 = 2-(pyridin-2-yl)benzo[d]thiazole and L2 = 2-(pyridin-4-yl)benzo[d]thiazole) are synthesized and characterized. The cadmium complex 1 is hexa-coordinated in which L1 act as N,N-chelate. The two acetate ligands of the complex bind to cadmium in monodentate and bidentate fashion. In the complex 2, the ligand L2 binds to cadmium ion through the nitrogen atom of the pyridine ring. The indium complexes 3 and 4 are hexa-coordinated; each has one L1 as chelating ligand and another L1 as molecule of crystallization. Fluorescence study revealed that the ligand L1 can detect indium(III) ions in the presence of cadmium(II) ions. In cell-based cytotoxicity assays, the ligands are biologically inactive, while the cadmium complexes 1 and 2 are cytotoxic in pancreatic cancer cell lines Mia Paca-2, BxPC-3 and Panc-1, with IC50 values as low as 16.0 μM.

Cadmium and indium complexes [Cd(L1)(O2CCH3)2(H2O)] (1) [Cd(L2)2(O2CCH3)2(H2O)] (2), [L1In(H2O)Cl3]·L1 (3) and [L1In(MeOH)Cl3]·L1.H2O (4) (where L1 = 2-(pyridin-2-yl)benzo[d]thiazole and L2 = 2-(pyridin-4-yl)benzo[d]thiazole) are synthesized and characterized. The cadmium complexes 1 and 2 are cytotoxic in pancreatic cancer cell lines Mia Paca-2, BxPC-3 and Panc-1, with IC50 values as low as 16.0 μM.Figure optionsDownload as PowerPoint slide