Time‐dependent cytotoxic properties of terpyridine‐based copper complexes

Abstract

Five copper complexes supported by terpyridine ligand were prepared and characterized, viz. [Cu3Cl4(Naphtpy)2][CuCl2] (1), [Cu2Cl2(Naphtpy)2](ClO4)2 (2), [CuCl2(Naphtpy)]2(MeOH)3(H2O) (3), [CuCl2(Cltpy)] (4) and [Cu(Cltpy)2](ClO4)2 (5); (where Naphtpy stands for 4'-((naphthalen-2-yl)methoxy)-2,2′:6′,2′′-terpyridine and Cltpy for 4′-chloro-2,2′:6′,2′′-terpyridine). Their DNA-interaction abilities were investigated, and their cytotoxic behaviors were examined with three cells lines, namely with human ovarian carcinoma cells (A2780) and its derived cisplatin-resistant line (A2780cis), and human cervix adenocarcinoma cells (HeLa). All compounds show good cytotoxic properties (especially after 72 h incubation). Remarkably, two compounds, i.e. 4 and 5, are almost inactive after 24 h (particularly 4), but are highly active after 72 h, with IC50 values in the low micromolar to submicromolar range. Compounds 1 and 2 induce necrosis, whereas late apoptosis is observed with 3−5, 4 exhibiting a behaviour close to that of cisplatin