Cytotoxic activity, albumin and DNA binding of new copper(II) complexes with chalcone-derived thiosemicarbazones

[Cu(HL)Cl2] complexes of chalcone-derived thiosemicarbazones were obtained with 3-phenyl-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCTPh), complex (1), 3-(4-chlorophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4ClPh), complex (2), 3-(4-bromophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4BrPh), complex (3), and 3-(4-nitrophenyl-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4NO2Ph), complex (4). 1–3 showed interaction with bovine serum albumin (BSA) and deoxyribonucleic acid from calf thymus (CT-DNA). The cytotoxic activities of the thiosemicarbazones and complexes (1–4) were tested against HL60 (wild type human promyelocytic leukemia), Jurkat (human immortalized line of T lymphocyte), MDA-MB 231 (human breast carcinoma) and HCT-116 (human colorectal carcinoma) tumor cell lineages. Upon coordination to copper(II) cytotoxicity significantly increased in Jurkat, MDA-MB 231 and HCT-116 cells. Unlike the free thiosemicarbazones, 1–4 induced DNA fragmentation in solid tumor cells indicating their pro-apoptotic potential. [Display omitted] •[Cu(HL)Cl2] complexes of chalcone-derived thiosemicarbazones were obtained.•The compounds were considerably cytotoxic against tumor cell lineages.•The Cu(II) complexes interact with DNA and bovine serum albumin (BSA).•On coordination to Cu(II) cytotoxic activity significantly increased.•Coordination to Cu(II) was a good strategy to promote apoptosis in solid tumor cells.