Biological activity and structure dependent properties of cuprous iodide complexes with phenanthrolines and water soluble tris (aminomethyl) phosphanes

This paper presents the biological activity of copper(I) iodide complexes with 1,10-phenanthroline (phen) or 2,9-dimethyl-1,10-phenanthroline (dmp) and three tris (aminomethyl) phosphanes: P(CH2N(CH2CH2)2NCH3)3 (1), P(CH2N(CH2CH2)2O)3 (2) and P (CH2N(CH3)CH2CH2OH)3 (3). Crystallographic and DFT data indicate a significantly stronger binding ability of 3 in the complexes [CuI (phen) P (CH2N (CH3)CH2CH2OH)3] (3P) and [CuI(dmp)P(CH2N(CH3)CH2CH2OH)3] (3N) in comparison to the 1 or 2 ligands. Most probably, this is caused by the relatively small steric requirements of 3. The complexes with dmp exhibit a very high in vitro activity against the Staphylococcus aureus strain (MIC — minimal inhibitory concentration: 2.5–5 μg/mL) and Candida albicans diploid fungus (MIC: 1.25–2.5 μg/mL). All the tested complexes also show a strong in vitro antitumor activity against human ovarian carcinoma cell lines: MDAH 2774 (IC50: 7–2 μM) and cisplatin-resistant SCOV 3 (IC50: 3–2 μM). Interestingly, the complexes with dmp of higher biological activity more weakly interact with bovine serum albumin (BSA) and less efficiently cleave the pBluescriptSK+ plasmid.

Copper(I) iodide complexes with phenanthrolines and tris(aminomethyl)phosphanes have a high in vitro antimicrobial and anticancer activity. Interestingly, the complexes with dmp (R′ = CH3) having higher activity, more weakly interact with BSA and less efficiently cleave the pBluescriptSK+ plasmid. The activity depends also on the PCu bond strength.Figure optionsDownload as PowerPoint slideResearch highlights
► New copper(I) iodide complexes with diimines and P(CH2N(Me)EtOH)3 are described.
► X-ray structure of [CuI (phen)P(CH2N(Me)EtOH)3] is presented.
► CuI complexes with tris(aminomethyl)phosphanes have a high biological activity.
► Activity of the compounds correlates with their interactions with biomolecules.
► The plasmid cleavage and interactions with BSA depend on the molecular structures.