Novel half-sandwich iridium(III) complexes with aminomethyl(diphenyl)phosphine derived from fluoroloquinolones (IrPCp, IrPSf, IrPLm, IrPNr) were studied as possible anticancer chemotherapeutics and showed higher potency than other well-known metal-based agents i.e., Pt(II) drugs. All compounds were characterized by elemental analysis, selected spectroscopic methods (i.e., absorption and fluorescence spectroscopy, NMR), ESI-MS spectrometry, X-ray diffraction, and electrochemical techniques. The studied complexes exhibited promising cytotoxicity in vitro with IC₅₀ values significantly lower than that of the reference drug – cisplatin. The insight into the mode of action revealed the uniform distribution of the Ir(III) complexes in both the nucleus and cytoplasm (Pearson's co-localization coefficient of 0.63). Precise cytometric analysis provided clear evidence for the predominance of apoptosis in the induced cell death. The activation of caspase-3/7 along with the decrease of mitochondrial membrane potential also confirmed the apoptotic cell death. The investigated Ir(III) complexes may induce changes in the cell cycle leading to G2/M phase arrest. ROS generation as a plausible pathway responsible for the cytotoxicity was confirmed by determination of redox potentials enabling efficient ROS production. Furthermore, Pluronic P-123 micelles loaded with selected Ir(III) complexes were proposed to overcome low solubility and to minimize serious systemic side effects by administering the complex in a controlled manner. The resulting nanoformulations (IrPCp_M, IrPNr_M) facilitated efficient drug accumulation for human lung adenocarcinoma and human prostate carcinoma (A549 and DU-145 cell lines), as demonstrated by confocal microscopy and ICP-MS analysis. In vitro cytotoxicity assays were also carried out within multicellular tumor spheroids and efficient anticancer action on these 3D assemblies was demonstrated.

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 Cu₂O₂Cl₂ 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.

Herein, we have synthesised and characterised a novel organic–inorganic hybrid crystal, [CH ₃ NH ₃ ] ₂ KCr(CN) ₆ ( MACr ).

To gain a better insight into the factors affecting the enhancement of the energy barrier in single molecule (single ion) magnets, three hexacoordinate cobalt(II) complexes based on the tridentate ligand 2,6-bis(pyrazol-1-yl)pyridine (pypz) and pseudohalide ions have been synthesized and investigated. It was found that dicyanoamido and azido ligands act as bridges to form a one dimensional network based on a single μ_1,5-dca bridge [Co(pypz)(dca)(H₂O]·dca (1) and dimer [Co₂(pypz)₂(μ_1,1-N₃)₂(N₃)₂]·2CH₃OH (2), while tcm⁻ counterbalanced the charge of [Co(pypz)₂]²⁺ in [Co(pypz)₂](tcm)₂ (3), where dca⁻ = dicyanamide ion; tcm⁻ = tricyanomethanide ion, respectively. The DC magnetic data show a sizable magnetic anisotropy, which was confirmed by high-field/high frequency EPR measurements. Two of them are SIMs (1 and 3) and the other one is a SMM (2). All complexes exhibit field induced slow magnetic relaxation with two (1 and 2) or three relaxation channels (3) and an exceptionally long relaxation time for the low-frequency channel upon application of an external field B_DC = 0.4, 0.3, and 0.4 T at T = 1.9 K; τ(LF) = 1.9, 2.1 and 0.9 s, respectively. Additionally, the high spin-reversal barriers, U = 103 K for 1 and 95 K for 2, are among the largest for field-induced SIMs for cobalt(II) reported in the literature.

This paper presents the synthesis, X-ray studies, spectroscopic characterization and variable temperature magnetic investigations and DFT calculation of four novel thiocyanato Cu(II) compounds [Cu(mpz)₂(NCS)₂]_n·nH₂O (1), {[Cu₂(dmpz)₄(NCS)₄][Cu(dmpz)(NCS)₂]}_n·2nMeOH (2) [(bdmpzm)Cu^II(SCN)₂(μ_1,3-SCN)Cu^I(bdmpzm)]_n (3) and [Cu(bpzpy)(NCS)₂] (4). Three of them (1, 2 and 3) display one-dimensional coordination structures while complex (4), incorporating a tridentate N-donor ligand, possesses a 0D molecular structure. Complex 3 belongs to a relatively rare group of mixed-valence Cu^II/Cu^I coordination polymers.