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We synthesized two derivatives of sparfloxacin ( HSf ): aminomethyl(diphenyl)phosphine ( PSf ) and its oxide ( OPSf ). The compounds were characterized by NMR spectroscopy, MS and elemental analysis. In addition, the molecular structures of the compounds were determined using DFT and X-ray ( OPSf ) analysis. The antibacterial activity of HSf and both derivatives was tested against four reference and fifteen clinical Gram-positive and Gram-negative strains of bacteria (sensitive or resistant to fluoroquinolones). The results showed that the activity of PSf was similar to or higher than the activity of HSf , while OPSf was found significantly less active. The compounds were also tested in vitro toward the following cancer cell lines: mouse colon carcinoma (CT26) and human lung adenocarcinoma (A549). Regardless of the cancer cell line, derivatization of HSf resulted in the gradual increase of cytotoxicity. OPSf exhibited the highest one (4 h – incubation time: IC50(CT26) = 51.0 ± 1.2; IC50(A549) = 74.9 ± 1.4 and 24 h: IC50(CT26) = 109.2 ± 8.8; IC50(A549) = 52.7 ± 9.2). [ABSTRACT FROM AUTHOR]

In this paper we present new copper(i) iodide or copper(i) thiocyanate complexes with hydroxymethyldiphenylphosphine (PPh2(CH2OH)) or phosphine derivatives of sparfloxacin, a 3rd generation fluoroquinolone antibiotic agent (PPh2(CH2–Sf)) and 2,9-dimethyl-1,10-phenanthroline (dmp) or 2,2′-biquinoline (bq) auxiliary ligands. The synthesised complexes were fully characterised by NMR and UV-Vis spectroscopy as well as by mass spectrometry. Selected structures were additionally analysed using X-ray and DFT methods. All complexes proved to be stable in solution in the presence of water and atmospheric oxygen for several days. The cytotoxic activity of the complexes was tested against two cancer cell lines (CT26 – mouse colon carcinoma and A549 – human lung adenocarcinoma). Applying two different incubation times, the studies enabled a preliminary estimation of the dependence of the selectivity and the mechanism of action on the type of diimine and phosphine ligands. The results obtained showed that complexes with PPh2(CH2–Sf) are significantly more active than those with PPh2(CH2OH). On the other hand, the relative impact of diimine on cytotoxicity is less pronounced. However, the dmp complexes are characterised by strong inhibitory properties, while the bq ones are rather not. This confirms the interesting and promising biological properties of the investigated group of copper(i) complexes, which undoubtedly are worthy of further biological studies. [ABSTRACT FROM AUTHOR]

Abstract: A novel bulky phosphine derived from 2-piperazinopyridine P(CH2N(CH2CH2)2N-2-py)3 (1) and its chalcogenide derivatives (oxide, sulfide and selenide) have been synthesized and characterized by elemental analysis, NMR spectroscopy and mass spectrometry. Next, two new copper(I) iodide or isothiocyanate complexes with 1 and 2,9-dimethyl-1,10-phenanthroline (dmp): [CuI(dmp)(1)] (1I) and [CuNCS(dmp)(1)] (1T), have been also synthesized and characterized by elemental analysis and studied by NMR, UV–vis, IR and luminescence spectroscopies. The X-ray structure of the complex 1T·1.81(CH3COCH3) was determined. The coordination geometry around the Cu(I) center is pseudo-tetrahedral with distortions resulting mostly from the molecular packing in the crystal cell. Both complexes exhibit orange photoluminescence in the solid state, which is much stronger for 1I than for 1T. The luminescence spectra of both complexes at room and 77K temperatures show relatively large bands with a typical batochromic shift accompanying the lowering of the temperature. On the basis of TDDFT calculations we interpreted these bands as of (MX,MPR3)LCT type resulting mainly from the transitions from the copper–iodine (or isothiocyanate) bonds and a small admixture of copper–phosphine bonds to antibonding orbitals of dmp diimine. [Copyright &y& Elsevier]

The copper(i) iodide or copper(i) isothiocyanate complexes with 2,9-dimethyl-1,10-phenanthroline (dmp) and two interesting aminomethylphosphanes: P(CH2N(CH2CH2)2O)3 (1) and novel P(CH2N(CH2CH2)2S)3 (2): CuI(dmp)P(CH2N(CH2CH2)2O)3 (1I), which was presented in our previous papers, CuI(dmp)P(CH2N(CH2CH2)2S)3 (2I), CuNCS(dmp)P(CH2N(CH2CH2)2O)3 (1T) and CuNCS(dmp)P(CH2N(CH2CH2)2S)3 (2T) are discussed in this work. The chemical structures of three new complexes were determined in solution by means of NMR spectroscopy and in solid state using X-ray measurements. For all presented complexes the coordination geometry about the Cu(i) centre is pseudo-tetrahedral showing the small flattening and large rocking distortions. All compounds crystallize as the discrete dimers bound by π-stacking interactions between dmp rings, which strongly depend on the phosphane ligand. Investigated complexes exhibit orange photoluminescence in the solid state of highly diversified intensity, position of the luminescence band and the lifetimes. On the basis of TDDFT calculations, the CT bands observed in UV-Vis spectra are assigned to the two mixed transitions from the CuX (X = I or NCS) bond with a small admixture of the CuP bond to π* orbitals of the dmp ligand: (MX,MPR3)LCT. However, emission bands can be interpreted to be of (MX)LCT type. [ABSTRACT FROM AUTHOR]

Abstract: Protonation equilibria and Cu(II) binding processes by an antifungal agent fluconazole, α-(2,4-difluorophenyl)-α-(1H-1,2,4-triazol-1-yl-methyl)-1H-1,2,4-triazole-1-ethanol, were studied using the UV–Vis, EPR and NMR spectroscopic techniques. The protonation constant of fluconazole was determined from NMR titration and attributed to N4′ nitrogen atoms using the DFT methods. The spectroscopic data suggest that at pH as low as 0.4 the first complex is formed, in which one or two Cu(II) ions are bound to one of the nitrogen atoms (N4′) from triazole rings. Above pH 1.5 each Cu(II) ion is surrounded by two nitrogen atoms (also N4′) from two different ligand molecules, forming primary monomeric complexes and above pH=5, both dimeric or oligomeric species occur, which is well registered by the EPR technique. The mixture of Cu(NO3)2 with fluconazole in a 1:1 molar ratio in a water (pH=4.5)/ethanol solution gave crystals of [Cu2(H2O){(C6H3-2,4-F2)(CH2N3C2H2)2C-OH}{(C6H3-2,4-F2)(CH2N3C2H2)2C-O}(NO3)](NO3)2·9(H2O). This complex is the first example of a cupric 3D polymeric structure with a fluconazole ligand coordinated via both N2′ and N4′ atoms from the same triazole rings. At higher pH values, we obtained a binuclear complex [Cu2(L)2(H2O)2(NO3)2], in which the copper(II) atoms were bridged by the oxygen atoms of the deprotonated of fluconazole. The hypothetical oxidative properties of this system were also examined, however it failed to generate either reactive oxygen species or DNA scission products. [Copyright &y& Elsevier]

Abstract: Two new platinum(II) complexes with tris(aminomethyl)phosphanes: [trans-PtCl2{P(CH2N(CH2CH2)2NCH3)3}2] (1Pt) and [trans-PtCl2{P(CH2N(CH2CH2)2O)3}2] (2Pt) were prepared and characterized with NMR and UV–Vis spectroscopies. Their structures were investigated by X-ray crystallography and DFT methods. TDDFT calculations were employed to interpret the electronic spectra of the complexes. Obtained results are not unequivocal, however population analysis indicate, that the character of HOMO and HOMO−1 orbitals depend strongly on the electron donoring properties of the phosphane ligand. Biological activity of 2Pt complex, which is more stable and more soluble in polar solvents than 1Pt, was examined in vitro on the Vero cell line (IC50 =12.5μM). At higher concentrations it induces apoptosis, probably due to changes of the cell cytoskeleton. Luminescence quenching studies and CD spectroscopy of interactions of 2Pt with HSA and BSA indicate that these albumins bind the complex slightly – without altering their tertiary structures, however HSA interacts with 2Pt noticeably stronger than BSA. It was also found that 2Pt does not cleave supercoiled pUC18 plasmid. [Copyright &y& Elsevier]

The new compounds 2,2'-bipyridine-3,3',6,6'-tetracarboxylic acid (bptcH4) (1) and iron(II) [Fe2(bptcH2)2(H2O)4].l4.74H2O (2) and [Co2(bptcH2)2(H2O)4].4.5H2O (3) have been prepared and characterized using 1H NMR, IR and UV-Vis spectroscopic methods. X-Ray structures of these compounds have been determined. Acid 1 crystallizes in the space group Aba2 and complexes 2 and 3 in P21/c. The metal atoms are coordinated with N and O atoms of 6,6' carboxylate groups of the bridging ligands and two aqua ligands. The crystals are stabilized by intra- and intermolecular O-H · · · N and OH · · · O hydrogen bonds. Magnetic moments of complexes 2 and 3 at room temperature are characteristic of the high spin Fe(II) and Co(II) compounds. The 1/χM dependences on temperature show weak antiferromagnetic interactions of 2 and 3. [ABSTRACT FROM AUTHOR]