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In this work three Ni 2+ complexes with general formula [NiCl 2 (Ph 2 P-N(R)-PPh 2 )], R = 2-CH 2 Py (Py = pyridine) - 1, CH 2 Ph (Ph = phenyl) - 2 and p-tol (p-tol = p-tolyl) - 3, were synthesized and characterized. These complexes were obtained in high yield by the reaction of NiCl 2 .6H 2 O and the corresponding diphenylphosphinoamine ligand (Ph 2 P-N(R)-PPh 2 ) in CH 2 Cl 2 /MeOH (1:1) solution, at room temperature (∼25 °C), and characterized by 1 H and 31 P { 1 H} NMR, vibrational spectroscopy in the infrared region, electronic spectroscopy in the UV-Vis regions, elemental analysis (%C, %H, %N) and single-crystal X-ray diffraction. The solution chemistry was studied in CDCl 3 /dmso-d 6 (dimethylsulfoxide) or neat dmso-d 6 using complex 2 as a model. The complexes were evaluated as cytotoxic agents against two cancer cells lines, A549 (lung cancer cells), B16F10 (melanoma cells) and the health cells HaCaT (human epithelial keratinocytes)., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Marcio Peres de Araujo reports financial support was provided by UFPR. Marcio Peres de Araujo reports a relationship with Coordenação de Aperfeiçoamento de Pessoal de Nível Superior that includes: funding grants. Marcio Peres de Araujo reports a relationship with National Council for Scientific and Technological Development that includes: funding grants., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Complexes with general formula [RuCl(η6-p-cymene)(P-NR-P)]X (R = CH2Py (Py = pyridine) - [1a]+, CH2Ph (Ph = phenyl) - [1b]+, Ph - [1c] and p-tol (p-tol = p-tolyl) - [1d]+; X = PF6- or BF4-) were evaluated as cytotoxic agents against two cancer cell lines (HeLa and MDA-MB-231). All metal complexes are active in the range of concentrations tested (up to 100 μmol L-1). The IC50 (μmol L-1) values for the metal complexes are lower than that found for cisplatin. The activities are up to 6- and 15-fold higher than cisplatin for HeLa and MDA-MB-231 cancer cell lines, respectively. Studies of DNA binding and DNA cleavage were performed. DNA binding studies revealed a modest hypochromic shift in the metal complexes electronic spectra, indicating a weak interaction with Kb values in the range of 1.7 × 103-1.6 × 104. Although the cleavage tests revealed that in the dark DNA is not a biological target for these metal complexes, upon blue light irradiation they are activated causing DNA cleavage. Electrochemical studies showed the presence of two independent redox processes, one attributed to the oxidation process of Ru2+ → Ru3+ (EC process) and the other one to the reduction of Ru2+ → Ru1+, which is further reduced to Ru0 (ECE mechanism). In both processes, coupled chemical reactions were observed. DFT calculations were performed to support the electrochemical/chemical behavior of the complexes. The reactivity of complex [1b]BF4 with CH3CN was evaluated and two complexes were isolated [2b]BF4 and [3b]BF4. The complex mer-[RuCl(CH3CN)3(P-NCH2Ph-P)]BF4 ([2b]BF4) was isolated after refluxing the precursor [1b]BF4 in CH3CN. Isomerization of [2b]BF4 in CH3CN resulted in the formation of fac-[RuCl(CH3CN)3(P-NCH2Ph-P)]BF4. An attempt to isolate the fac-isomer by adding diethyl ether was unsuccessful, and the complex [3b]BF4 was observed as the major component. The complex [Ru2(μ-Cl3)(CH3CN)2(P-NCH2Ph-P)2]BF4 ([3b]BF4) proved to be very stable and can be obtained from both the mer- and the fac-isomers. The molecular structures of [1b]BF4 and [3b]BF4 were solved by single-crystal X-ray diffraction.

Several ruthenium complexes have been investigated regarding anti-Mycobacterium tuberculosis (anti-MTb) activity, with some diphosphine-containing ruthenium complexes comparable to first and second line drugs. However, to the best of our knowledge, there is no PNP-containing ruthenium complexes applied as metallodrugs. Thus, this study focused on the synthesis, characterization and anti-MTb activity of a new series of coordination compounds with general formula [RuCl(η 6 -p-cymene)(PN R P)]X (R=CH 2 Py (Py=pyridine)-[1a], CH 2 Ph (Ph=phenyl)-[1b], Ph-[1c] and p-tol (p-tol=p-tolyl)-[1d]; X=PF 6 - or BF 4 - P{ 1 H, 31 P{ 1 H}), vibrational spectroscopy (FTIR), ESI-MS, molar conductance, elemental analysis and X-ray diffraction studies. The molecular structures of [1a]PF 6 , [1c]BF 4 and [1d]PF 6 were determined and confirm the spectroscopic and ESI-MS data. The complexes were used in anti-MTb trials, and the preliminary results are presented. The complexes are promising anti-MTb agents with MIC 90 (Minimum Inhibitory Concentration of compounds required to inhibit the growth of 90% of MTb) values comparable with the Ethambutol, the reference drug used in this work, and complex [1a]BF 4 presented the highest selectivity index., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The synthesis and characterization of ruthenium compounds of the type [RuCl(2)(NO)(dppp)(L)]PF(6) [dppp=1,3-bis(diphenylphosphino)propane; L=pyridine, 4-methylpyridine, 4-phenylpyridine and dimethyl sulfoxide] are described. The complexes were characterized by elemental analysis, UV/Vis and infrared spectroscopy, cyclic voltammetry, and X-ray crystallography for the complexes with the pyridine and 4-methylpyridine ligands. In vitro evaluation of these nitrosyl complexes revealed cytotoxic activity from 7.1 to 19.0 microM against the MDA-MB-231 breast tumor cells and showed that, in this case, they are more active than the reference metallodrug cisplatin. The 1,3-bis(diphenylphosphino)propane and the N-heterocyclic ligands alone failed to show cytotoxic activities at the concentrations tested (maximum concentration utilized=200 microM).