Water-soluble and photo-stable silver(I) dicarboxylate complexes containing 1,10-phenanthroline ligands: Antimicrobial and anticancer chemotherapeutic potential, DNA interactions and antioxidant activity

The complexes [Ag2(OOC–(CH2)n–COO)] (n=1–10) (1–10) were synthesised and reacted with 1,10-phenanthroline (phen) to yield derivatives formulating as [Ag2(phen)x(OOC–(CH2)y–COO)]·zH2O (x=2 or 3; y=1–10; z=1–4) (11–20) which are highly water-soluble and photo-stable in aqueous solution. The phen derivatives 11–20 exhibit chemotherapeutic potential against Candida albicans, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and against cisplatin-sensitive breast (MCF-7) and resistant ovarian (SKOV-3) cancer cell lines. Cyclic voltammetric analysis and DNA binding and intercalation studies indicate that the mechanism of action of 11–20 is significantly different to that of their silver(I) dicarboxylate precursors and they do not induce DNA damage or ROS generation in mammalian cells. The representative complexes 9 and 19 (containing the undecanedioate ligand) were both found to significantly reduce superoxide and hydrogen peroxide induced oxidative stress in the yeast S. cerevisiae. Water-soluble and photo-stable silver-dicarboxylate-phenanthroline complexes exhibit antimicrobial and cytotoxic properties. The representative complex [Ag2(phen)3(OOC–(CH2)9–COO)]·3H2O (19) and its precursor [Ag2(OOC–(CH2)9–COO)] (9) bind DNA, do not induce double strand DNA damage or ROS generation in mammalian cells, and they reduce superoxide and hydrogen peroxide induced oxidative stress in the yeast S. cerevisiae. [Display omitted] •Water-soluble and photo-stable silver(I)-dicarboxylate-phen complexes•Clinically relevant in vitro antimicrobial and anticancer capabilities•Exceptional in vitro DNA intercalating properties.•Incapable of causing DNA double strand damage in mammalian cells.•Reduce O2‾ and H2O2 induced oxidative stress in the yeast S. cerevisiae.