Copper(ii) complexes with 2-ethylpyridine and related hydroxyl pyridine derivatives: structural, spectroscopic, magnetic and anticancer in vitro studies. Issue 42 (28th September 2022)

• Record Type: Journal Article
• Authors: Malik, Magdalena; Świtlicka, Anna; Bieńko, Alina; Komarnicka, Urszula K.; Bieńko, Dariusz C.; Kozieł, Sandra; Kyzioł, Agnieszka; Mazur, Tomasz; Machura, Barbara
• Is Part Of: RSC advances. Volume 12:Issue 42(2022)
• Page Start: 27648
• Page End: 27665
• Publication Date: 2022-09-28
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d2ra05133h
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Four solution-stable copper(ii ) complexes of pyridine and pyridine-based alcohols were investigated by spectroscopic and thermal methods; the magnetic and anticancer properties were discussed as well. Abstract : Copper(ii ) complexes with 2-ethylpyridine (1 and 2 ), 2-(hydroxyethyl)pyridine (3 ) and 2-(hydroxymethyl)pyridine (4 ) have been synthesized and characterized. All inorganic compounds have been studied by X-ray diffraction, thermogravimetry, vibrational and EPR spectroscopy as well as theoretical methods. The geometry of the complexes 1, 3 and 4 adopts nearly perfect geometry close to square planar (1, 4 ) or square pyramid (3 ) stereochemistry, respectively. The distortion of five coordinated copper(ii ) ions in complex 2 indicates intermediate geometry between square pyramidal and trigonal pyramidal geometry. Further, the magnetic measurements have shown antiferromagnetic behaviour of the prepared complexes in a wide range of temperatures. The antiferromagnetic behaviour of 2 should originate from the superexchange interactions between each copper(ii ) ion by the mixed chloride and μ4 -O ion pathways. Besides, the weak antiferromagnetic character of 2 can be also attributed to the presence of intrachain exchange between dimeric units through double oxide ion. In complex 3, strong antiferromagnetic coupling between Cu(ii ) centres in the Cu2 O2 Cl2 moiety is found. The cytotoxicity of all compounds was tested in vitro against various cancer cell lines: human lung adenocarcinoma (A549), human breast adenocarcinoma (MCF7), human prostate carcinoma; derived from metastatic site: brain (DU-145) and two normal cell lines: human embryonic kidney (HEK293T) and human keratinocyte (HaCat). Furthermore, Pluronic P-123 micelles loaded with selected complexes (1 and 3 ) were proposed to overcome low solubility and to minimize systemic side effects. More detailed study revealed that complex 3 loaded inside micelles causes DU-145 cells' death with simultaneous decrease of mitochondrial membrane potential and a high level of reactive oxygen species generation. The stability of the compounds 1–4 in DMSO was confirmed by UV-Vis and FT-IR spectra studies.