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Abstract: Reaction of the vitamin K3 derivative menadione sodium bisulfite thiosemicarbazone (NaK3TSC) with chloro(triethylphosphine)gold(I) afforded the complex [AuPEt3(K3TSC)]. This compound consists of discrete molecules in which the metal is almost linearly coordinated to P and S. Preliminary in vitro screening showed significant anti-cancer activity, notably against the cisplatin-resistant cell line A2780cis. [Copyright &y& Elsevier]

The crystal structure of the title compound, [Hg(C11H8N)(C12H22PS2)], consists of mol­ecules in which the Hg atom is coordinated strongly to the C atom in position 2 of the phenyl group and to one of the di­thio­phosphinate S atoms, and at longer distances to the pyridine N atom and the other S atom. The C-Hg-S fragment involving the S atom more strongly bound to Hg is almost linear [C-Hg-S = 178.9 (3)°]. [ABSTRACT FROM AUTHOR]

Four new Cu/PPh3/naphtoquinone complexes were synthesized, characterized (IR, UV/visible, 1D/2D NMR, mass spectrometry, elemental analysis, and X-ray diffraction), and evaluated as anticancer agents. We also investigated the reactive oxygen species (ROS) generation capacity of complex 4, considering the well-established photochemical property of naphthoquinones. Therefore, employing the electron paramagnetic resonance (EPR) "spin trap", 5,5-dimethyl-1-pyrroline N-oxide (DMPO) technique, we identified the formation of the characteristic •OOH species (hydroperoxyl radical) adduct even before irradiating the solution containing complex 4. As the irradiation progressed, this radical species gradually diminished, primarily giving rise to a novel species known as •DMPO-OH (DMPO + •OH radical). These findings strongly suggest that Cu(I)/PPh3/naphthoquinone complexes can generate ROS, even in the absence of irradiation, potentially intensifying their cytotoxic effect on tumor cells. Interpretation of the in vitro cytotoxicity data of the Cu(I) complexes considered their stability in cell culture medium. All of the complexes were cytotoxic to the lung (A549) and breast tumor cell lines (MDA-MB-231 and MCF-7). However, the higher toxicity for the lung (MRC5) and breast (MCF-10A) non-tumoral cells resulted in a low selectivity index. The morphological analysis of MDA-MB-231 cells treated with the complexes showed that they could cause decreased cell density, loss of cell morphology, and loss of cell adhesion, mainly with concentrations higher than the inhibitory concentration of 50% of cell viability (IC50) values. Similarly, the clonogenic survivance of these cells was affected only with concentrations higher than the IC50 values. An antimigratory effect was observed for complexes 1 and 4, showing around 20–40% of inhibition of wound closure in the wound healing experiments. [ABSTRACT FROM AUTHOR]

Copper nitrite reductase mimetics were synthesized using three new tridentate ligands sharing the same N,N,N motif of coordination. The ligands were based on L -proline modifications, attaching a pyridine and a triazole to the pyrrolidine ring, and differ by a pendant group (R = phenyl, n-butyl and n-propan-1-ol). All complexes coordinate nitrite, as evidenced by cyclic voltammetry, UV-Vis, FTIR and electron paramagnetic resonance (EPR) spectroscopies. The coordination mode of nitrite was assigned by FTIR and EPR as κ2O chelate mode. Upon acidification, EPR experiments indicated a shift from chelate to monodentate κO mode, and 15N NMR experiments of a Zn2+ analogue, suggested that the related Cu(II) nitrous acid complex may be reasonably stable in solution, but in equilibrium with free HONO under non catalytic conditions. Reduction of nitrite to NO was performed both chemically and electrocatalytically, observing the highest catalytic activities for the complex with n-propan-1-ol as pendant group. These results support the hypothesis that a hydrogen bond moiety in the secondary coordination sphere may aid the protonation step. [ABSTRACT FROM AUTHOR]

The octahedral title compound, [Ru(C2H5O)(NO)(NO2)2(C6H16N2)], crystallizes in the rhombohedral space group P31 with an ethoxy ligand axially coordinated trans to the nitro­syl ligand. The RuII ion is equatorially coordinated by a tetramethylethylenediamine group acting as a bidentate ligand, and to two nitro moieties whose planes are tilted with respect to the mean equatorial plane. Each nitro­gen ligand bonded to the metallic centre has a different hybridization state. [ABSTRACT FROM AUTHOR]

Herein we report the synthesis and characterization of a new copper(I) complex with triphenylphosphine (PPh3) and N‐(2‐thiophenecarbonyl)‐N'‐(3‐Cl, 4‐F‐phenyl)thiourea (HL), as ligands. The complex was characterized by vibrational (FTIR and FT‐Raman) and multinuclear (1H, 13C {1H}, 31P{1H}) NMR spectroscopies. The crystalline structure of the complex was determined by single‐crystal X‐ray diffraction, confirming that a neutral binuclear compound, identified as [Cu(PPh3)(L‐κ2‐N,μ‐S)]2, was obtained. The anionic thiourea ligand coordinates to the metal through the sulfur and nitrogen atoms in an unusual bidentate κ2‐N,μ‐S coordination mode. The complex is a dimer sited on a crystallographic center of symmetry. Each Cu2(μ‐S)2 cation bridges trough the sulfur atoms of two symmetry related thiourea moieties and is also coordinated to the nitrogen atom of the thiourea ligand and the phosphorus atom from PPh3 co‐ligand, forming a slightly distorted tetrahedral geometry. An intramolecular N−H⋅⋅⋅O=C hydrogen bond is observed in the anionic ligand, forming a six‐membered ring that stabilizes the N−H thioamide group. Hirshfeld surface analysis shows that the molecules are connected by weak intermolecular contacts C⋅⋅⋅C, H⋅⋅⋅C and H⋅⋅⋅H which add to the stability of the crystalline packing. The in vitro cytotoxicity study of the complex indicates that it is more active against human lung carcinoma cells (A549), when compared to the free ligand. [ABSTRACT FROM AUTHOR]

Abstract: A polymeric complex [Eu(α-tpc)3(α-Htpc)2] n and its characterization by single crystal X-ray and thermal analysis, infrared and photoluminescence spectroscopies are described. The compound crystallizes in the monoclinic Cc space group. The asymmetric unit is formed from a europium ion bonded to one carboxyl oxygen of five different thiophene carboxylic moieties. Three of these moieties are deprotonated and bridge between neighboring europium ions giving rise to an infinite polymer along the c axis. Besides the europium characteristic emission lines, the emission spectra show unambiguously the crystal size effect on the 5D0 → 7F0 transition. The complex thermal decomposition at 220°C leads to a stable luminescent complex in which the 5D0 → 7F4 transition reveals a monomeric characteristic. The Judd–Ofelt intensity parameters to the polymeric and the monomeric compound with the same ligand and coordination number were compared. [Copyright &y& Elsevier]

Abstract: The compound [PbPh2(NO3)2(H2O)2] was synthesized and characterized by spectroscopic methods (IR; 1H, 13C and 207Pb NMR) and mass spectrometry. An X-ray diffraction study showed that the crystal is a supramolecular tridimensional network of hydrogen-bonded PbPh2(NO3)2(H2O)2 units in which the Pb atom is octacoordinated and adopts a distorted hexagonal bipyramidal geometry, with four O (bidentate nitrate) and two O (water) atoms in equatorial positions and two C-phenyl atoms in axial positions. The crystal of [PbMe3(NO3)(H2O)], obtained as a byproduct in the synthesis of PbMe2(NO3)2, contains chains of hydrogen-bonded PbMe3(NO3)(H2O) units in which the Pb atom is pentacoordinated with a slightly distorted trigonal bipyramidal environment. In this arrangement the three C-methyl atoms are equatorial and the O atoms from the monodentate nitrate and the water molecule are axial. [Copyright &y& Elsevier]

Abstract: 2-Benzoylpyridine semicarbazone (H2BzPS) and its complexes [Cu(H2BzPS)Cl2] (1) and [Zn(H2BzPS)Cl2] (2) have been synthesized and their spectral properties have been studied. The electrochemical behaviour of [Cu(H2BzPS)Cl2] (1) has been investigated. [Cu(H2BzPS)Cl2] (1) crystallizes in the triclinic P-1 space group, a=9.278(1), b=12.848(1), c=13.923(1) Å, α=84.54(1), β=71.91(1), γ=85.14(1)°, with two complexes per asymmetric unit (Z=4) and a disordered methanol solvent molecule (occupancy=1/4). [Zn(H2BzPS)Cl2] (2) crystallizes in the orthorhombic P212121 space group with a=11.983(1), b=14.067(1), c=18.706(1) Å, and two independent molecules per asymmetric unit (Z=8). In both cases, the neutral semicarbazone acts as a tridentate ligand which coordinates the metal through the pyridine and imine nitrogen atoms and the carbonyl oxygen. Two chloride ions occupy the fourth and fifth coordination positions. [Copyright &y& Elsevier]

We have synthesized and characterized three new ruthenium(II) diphosphine complexes containing an acylthiourea ligand, with the general formula [Ru(DPEPhos)(O,S)(bipy)]PF6, where DPEPhos = bis(2-(diphenylphosphino)phenyl)ether, bipy = 2,2′-bipyridine, and O,S = N,N-dimethyl-N′-(benzoyl)thiourea (1), N,N-dimethyl-N′-(furoyl)thiourea (2), and N,N-dimethyl-N′-(thiophenyl)thiourea (3), by several physicochemical techniques. We evaluated the ruthenium complexes for their cytotoxicity against two human cancer cell lines, A549 (lung) and MDA-MB-231 (breast), and two corresponding lines of non-cancer cells, MRC-5 (lung) and MCF-10A (breast). All the complexes are cytotoxic against the cancer cell lines; the IC50 values lie in the micromolar range (0.07–0.70 μM). Ruthenium complex 1 is more selective (7 times more active) toward lung cancer cells (A549) than toward non-cancer cells (MRC-5) and is 160 times more cytotoxic than cisplatin against A549 cells. Investigations of the mechanism of action of complex 1 in A549 cells demonstrated that it inhibits colony formation and promotes cell cycle arrest in the G1 phase and apoptotic cell death. DNA binding studies revealed that complexes 1–3 interact with the biomolecule via minor grooves. These complexes also interact with human serum albumin (HSA) and have affinity for site I by hydrophobic forces. Therefore, this new class of ruthenium complexes can act as cytotoxic agents, mainly for lung cancer treatment. [ABSTRACT FROM AUTHOR]

The bis{(μ2-chloro)[2-(imidazol-4-yl)ethyl][(1-methylimidazol-2-yl)methyl]amine}dicopper(II) bis[tetrachloro-cuprate (II)] complex [Cu2(HISMIMA)2Cl2]2(CuCl4)2 (HISMIMA:[(2-(imidazol-4-yl)ethyl)(1-methylimidazol-2-yl)methyl)amine]) was obtained by serendipity during the reaction of the mononuclear [Cu(HISMIMA)Cl2] complex and gaseous nitric oxide in methanolic solution. The title complex unit cell has the composition: an anion complex {[Cu2(HISMIMA)2Cl2][CuCl4]2}2- (1) and a cation complex [Cu2(HISMIMA)2Cl2]2+ (2). Cation 2 displays a crystallographic centrosymmetric Cu2Cl2 core with each CuII atom coordinated to the tripodal ligand in a square pyramidal geometry (Addison parameter τ=0.07). In 1, a distorted octahedral geometry is observed, in which the CuII ions are coordinated in a way similar to that in 2 but with an additional interaction with the [CuCl4]2- ions. Cyclic voltammetric experiments reveal that the title complex does not dissociate in acetonitrile solution and has E1/2=-0.24 V vs NHE (ΔEp=0.19 V, ipa/ipc=0.75) for the CuIICuII to CuICuI process at the Cu(μ-Cl)2Cu core. [Copyright &y& Elsevier]

Herein we discuss five ruthenium(II) complexes with good cytotoxicity against cancer cells. These complexes are named [Ru(tzdt)(bipy)(dppb)]PF6 (1), [Ru(mmi)(bipy)(dppb)]PF6 (2), [Ru(dmp)(bipy)(dppb)]PF6 (3), [Ru(mpca)(bipy)(dppb)]PF6 (4) and [Ru(2mq)(bipy)(dppb)]PF6 (5), where tzdt = 1,3-thiazolidine-2-thione, mmi = mercapto-1-methyl-imidazole, dmp = 4,6-diamino-2-mercaptopyrimidine, mpca = 6-mercaptopyridine-3-carboxylic acid, 2mq = 2-mercapto-4(3H)-quinazolinone, bipy = 2,2′-bipyridine and dppb = 1,4-bis(diphenylphosphino)butane. In vitro cell culture experiments revealed significant cytotoxic activity for 1–5 against MDA-MB-231, MCF-7, A549, DU-145 and HepG2 tumor cells, higher than that for the standard anticancer drug cisplatin. Compound/DNA interaction studies were carried out showing that 1–5 interact with DNA by electrostatic force of attraction or by hydrogen bonding. Moreover, the complexes interact, moderately and spontaneously, with human serum albumin (HSA) through the hydrophobic region. The five complexes are able to inhibit the DNA supercoiled relaxation mediated by human topoisomerase IB (TopIB), and complex 1 is found to be the most efficient TopIB inhibitor among the five compounds. The inhibitory effect and analysis of different steps of the TopIB catalytic cycle indicate that complex 1 inhibits the cleavage reaction impeding the binding of the enzyme to DNA and has no effect on the religation step. Complexes 1, 2 and 3 did not show mutagenic activity when they were evaluated by the cytokinesis-block micronucleus cytome assay in HepG2 cells and the Ames test in the presence and absence of mouse liver S9 metabolic activation. Therefore, it is necessary to perform further in-depth analysis of the therapeutic potential of these promising ruthenium complexes as anticancer drugs. [ABSTRACT FROM AUTHOR]

In this study, Ru(II)-arene complexes with acylthiourea ligands of the type [Ru( η 6 ‑ p ‑cymene)(PPh 3 )(T)Cl]PF 6 ( 1 – 5 ) and [Ru( η 6 ‑ p ‑cymene)(PPh 3 )(T)]PF 6 ( 1a , 4a ), where PPh 3  = triphenylphosphine and T = N‑acyl‑N′(monosubstituted)thiourea, were synthesized and characterized, and their cytotoxic properties were also evaluated. 1a and 4a were obtained from the hydrolysis reaction of 1 and 4 . All complexes showed unusual coordination modes for acylthiourea ligands, which are coordinated in a monodentate fashion (S) in 1 – 5 , while they found to be bidentate (S,N), in 1a and 4a . To the best of our knowledge, 1a and 4a are the first crystallographically reported ruthenium compounds with acylthiourea coordinated via S and N(amide) atoms. The cytotoxicity of the compounds was evaluated in human lung cells, A549 and MRC-5. The IC 50 values ranging from 0.25 to 0.61 μM after 48 h incubation in lung cancer cells indicate that the compounds showed high cytotoxicity with values significantly lower than the reference drug, cisplatin (11.84 μM). Interaction studies were carried out using human serum albumin (HSA) and DNA. All complexes showed similar cytotoxic activity, however complex 1a , which is the hydrolysis product of 1 , presented the highest activity and selectivity among all seven compounds synthesized here. Complexes 1 and 1a inhibited the colony formation decreasing the colony size and inducing morphology changes in A549 cells. These complexes induced apoptosis cell death and promoted cell cycle arrest in the Sub-G1 phase with a decrease in the cell number at the S phase. [ABSTRACT FROM AUTHOR]

We report here on three new ruthenium(II) complexes, [Ru(DPEPhos)(mtz)(bipy)]PF 6 (Ru1), [Ru(DPEPhos)(mmi)(bipy)]PF 6 (Ru2) and [Ru(DPEPhos)(dmp)(bipy)]PF 6 (Ru3). DPEPhos = bis -[(2-diphenylphosphino)phenyl]ether, mtz = 2-mercapto-2-thiazoline, mmi = 2-mercapto-1-methylimidazole, dmp = 4,6-diamino-2-mercaptopyrimidine and bipy = 2,2′-bipyridine. The compounds were characterized by several spectroscopic techniques, and the molecular structure of Ru1 complex was determined by single-crystal X-ray diffraction. The cytotoxicity of Ru1 – Ru3 complexes were tested against the A549 (human lung) and the MDA-MB-231 (human breast) cancer cell lines and against MRC-5 (non-tumor lung) and MCF-10A (non-tumor breast) cell lines through the MTT assay. All three complexes are cytotoxic against the cell lines studied, with IC 50 values lower than those found for the cisplatin. Among them, the Ru2 complex has shown the best selectivity against MDA-MB-231 cancer cell lines, with an IC 50 value 12 times lower than that on MCF-10A. The complex Ru2 was capable to induce changes in MDA-MB-231 cells morphology, with loss of cellular adhesion, inhibited colony formation and induce an accumulation of cells at the sub-G1 phase, with an increase in S-phase and decrease of cells at G2 phase. Viscosity, electrochemical and Hoechst 33258 displacement experiments for Ru1 – Ru3 complexes with calf thymus DNA (CT-DNA) showed an electrostatic and groove binding mode of interaction. Additionally, the complexes interact with the protein Human Serum Albumin (HSA) by static mechanism. The negative values for ΔH and ΔS indicate that van der Waals forces and hydrogen bonding may occurs between the complexes and HSA. Therefore, this class of complexes are promising anticancer candidates and may be selected to further detailed studies. N,S-mercapto ligands can form new ruthenium compounds with promising cytotoxic activity against cancer cell lines. [Display omitted] • Ru(II)/N,S-mercapto complexes with promising anticancer properties. • Cytotoxic activity against breast and lung cancer cells. • Selectivity is reported against breast cancer cells. • Complexes interact with CT-DNA and Human Serum Albumin (HSA). • Complex inhibited colony formation and induce an accumulation of cells at the sub-G1 phase. [ABSTRACT FROM AUTHOR]

The new complexes of Pd(II) with N , N -disubstituted- N ′-acylthioureas:[( 1 ) [Pd(dppf)( N , N -dimethyl- N ′-benzoylthioureato-k 2 O,S)]PF 6 , ( 2 ) [Pd(dppf)( N , N -diethyl- N ′-benzoylthioureato-k 2 O,S)]PF 6 , ( 3 ) [Pd(dppf)( N , N -dibuthyl- N ′-benzoylthioureato-k 2 O,S)]PF 6 , ( 4 ) [Pd(dppf)( N , N -diphenyl- N ′-benzoylthioureato-k 2 O,S)]PF 6 , ( 5 ) [Pd(dppf)( N , N -diethyl- N ′-furoylthioureato-k 2 O,S)]PF 6 , ( 6 ) [Pd(dppf)( N , N -diphenyl- N ′-furoylthioureato-k 2 O,S)]PF 6 , ( 7 ) [Pd(dppf)( N , N -dimethyl-N′- thiophenylthioureato-k 2 O,S)]PF 6 , and ( 8 ) [Pd(dppf)( N , N -diphenyl-N′-thiophenylthioureato-k 2 O,S)]PF 6 , were prepared and characterized by elemental analysis, and spectroscopic techniques. The structures of complexes ( 2 ), ( 3 ), ( 5 ), ( 6 ) and ( 8 ) had their structures determined by X-ray crystallography, confirming the coordination of the ligands with the metal through sulfur and oxygen atoms, forming distorted square-planar geometries. These complexes have shown antibacterial activity against anti- Mycobacterium tuberculosis H37Rv ATCC 27294. The complexes exhibited antiparasitic activity against Trypanosoma cruzi , while the metal-free thioureas did not. The results demonstrated that the compounds described here can be considered as promising anti- Mycobacterium tuberculosis and anti- T. cruzi agents, since in both cases their in vitro activity were better than reference drugs available for the treatment of both diseases. [ABSTRACT FROM AUTHOR]

1-Acyl thioureas [R 1 C(O)NHC(S)NR 2 R 3 ] are shown to display conformational flexibility depending on the degree of substitution at the nitrogen atom. The conformational landscape and structural features for two closely related thioureas having R 1 = 2-furoyl have been studied. The un-substituted 2-furoyl thiourea ( I ) and its dimethyl analogue, i.e. 1-(2-furoyl)-3,3-dimethyl thiourea ( II ), have been synthesized and fully characterized by spectroscopic (FT-IR, 1 H and 13 C NMR) and elemental analysis. According to single crystal X-ray diffraction analysis, compounds I and II crystallize in the monoclinic space group P21/c. In the compound I , the trans–cis geometry of the almost planar thiourea unit is stabilized by intramolecular N H ⋯ O C hydrogen bond between the H atom of the cis thioamide and the carbonyl O atom. In compound II , however, the acyl thiourea group is non-planar, in good agreement with the potential energy curve computed at the B3LYP/6-31 + G(d,p) level of approximation. Centrosymmetric dimers generated by intermolecular N H ⋯ S C hydrogen bond forming R 2 2 (8) motif are present in the crystals. Intermolecular interactions have been rationalized in terms of topological partitions of the electron distributions and Hirshfeld surface analysis, which showed the occurrence of S ⋯ H, O ⋯ H and H ⋯ H contacts that display an important role to crystal packing stabilization of both thiourea derivatives. [ABSTRACT FROM AUTHOR]

Three new mixed and mononuclear Ru(II) complexes containing 1,3-thiazolidine-2-thione (tzdtH) were synthesized and characterized by spectroscopic analysis, molar conductivity, cyclic voltammetry, high-resolution electrospray ionization mass spectra and X-ray diffraction. The complexes presented unique stereochemistry and the proposed formulae are: [Ru(tzdt)(bipy)(dppb)]PF6 ( 1 ), cis -[Ru(tzdt) 2 (PPh 3 ) 2 ] ( 2 ) and trans -[Ru(tzdt)(PPh 3 ) 2 (bipy)]PF 6 ( 3 ), where dppb = 1,4-bis(diphenylphosphino)butane and bipy = 2,2′-bipyridine. These complexes demonstrated strong cytotoxicity against cancer cell lines when compared to cisplatin. Specifically, complex 2 was the most potent cytotoxic agent against MCF-7 breast cells, while complexes 1 and 3 were more active in DU-145 prostate cells. Binding of complexes to ctDNA was determined by UV–vis titration and viscosity measurements and revealed binding constant (K b ) values in range of 1.0–4.9 × 10 3 M − 1 , which are characteristic of compounds possessing weak affinity to ctDNA. In addition, these complexes presented antiparasitic activity against Trypanosoma cruzi . Specifically, complex 3 demonstrated strong potency, moderate selectivity index and acted in synergism with the approved antiparasitic drug, benznidazole. Additionally, complex 3 caused parasite cell death through a necrotic process. In conclusion, we demonstrated that Ru(II) complexes have powerful pharmacological activity, while the metal-free tzdtH does not provoke the same outcome. [ABSTRACT FROM AUTHOR]

Synthesis, characterization and anti- Mycobacterium tuberculosis assays of new platinum(II)/dppf/ N , N -disubstituted- N ′-acyl thiourea complexes with general formulae [Pt(dppf)(L)]PF 6 , [dppf = 1,1′-bis(diphenylphosphino)ferrocene; L = N , N -disubstituted- N ′-acyl thioureas] is reported. The complexes were characterized by elemental analysis, molar conductivity, IR, NMR ( 1 H, 13 C and 31 P{ 1 H}) spectroscopy. The spectroscopic data are consistent with the complexes containing one dppf and one O, S chelated ligand. The crystal structures of complexes with N , N -diphenyl- N ′-benzoylthiourea (L4) , N , N -diethyl- N ′-furoylthiourea (L5) and N , N- diphenyl- N ′-(thiophene-2-carbonyl)thiourea (L8) were determined by X-ray crystallography, confirming the coordination of the ligands with the metal through sulfur and oxygen atoms, forming distorted square-planar structures. The complexes were screened with respect to their anti- M. tuberculosis activity (H37Rv ATCC 27294). [ABSTRACT FROM AUTHOR]

In this work, group 10 transition metal complexes bearing dppe [1,2- bis (diphenylphosphino)ethane] and acylthiourea ligands were evaluated for their cytotoxic and antiparasitic activities. Six new complexes with a general formula [M(L n)(dppe)]BF 4 [where M = NiII, PdII or PtII; L n = N , N ′-dimethyl-N-benzoyl thiourea (L 1) or N , N ′-dimethyl-N-tiofenyl thiourea (L 2) were synthesized and characterized by infrared, NMR (31P{1H}, 1H and 13C{1H}) spectroscopies, elemental analysis and molar conductivity. The structures of the complexes were confirmed by X-ray diffraction technique. The biological activity of the complexes was evaluated on breast cancer cells (MDA-MB-231 and MCF-7) and causative agents of chagas disease and leishmaniasis. The complexes presented higher cytotoxicity for breast cancer cell lines compared to non-tumor cells. Nickel complexes stood out when evaluated against the triple-negative breast cancer line (MDA-MB-231), presenting considerably lower IC 50 values (about 10 to 22×), when compared to palladium and platinum complexes, and the cisplatin drug. When evaluated on the triple-negative line (MDA-MB-231), the complexes [Ni(L 2)(dppe)]BF 4 (2), [Pd(L 2)(dppe)]BF 4 (4) and [Pt(L 2)(dppe)]BF 4 (6) were able to induce cell morphological changes, influence on the cell colony formation and the size of the cells. The complexes inhibit cell migration and cause changes to the cell cytoskeleton and nuclear arrangement. In the same cell line, the compounds caused cell arrest in the Sub-G1 phase of the cell cycle. The compounds were also tested against the Trypanosom Cruzi (T. cruzi) and Leishmania sp. parasites, which cause Chagas and leishmaniasis disease, respectively. The compounds showed good anti-parasitic activity, mainly for T. cruzi, with lower IC 50 values, when compared to the commercial drug, benznidazole. The compounds interact with CT-DNA, indicating that interaction occurs by the minor groove of the biomolecule. Phosphinic complexes of group 10 metals with acylthioureas ligands were evaluated for their cytotoxic and antiparasitic activities. Complexes were active against breast cancer tumor cells, Trypanosome Cruzi (T. cruzi), and Leishmania sp. parasites. Compounds 2 , 4, and 6 altered the cytoskeleton, induced nuclear alterations, and caused cell arrest in the Sub-G1 phase of the cell cycle in MDA-MB-231 cells. Studies indicated the interaction of compounds in the DNA minor groove. [Display omitted] • New metal-acylthiourea complexes were synthesized. • The complexes interact with the DNA, through the minor groove, and with the HSA. • The cytotoxicity of the compounds was significant in breast tumor cell lines. • The compounds were active against Chagas disease and leishmaniasis. • Complexes 2, 4 and 6 caused cell arrest in the Sub-G1 phase of the cell cycle, in MDA-MB-231 cells. [ABSTRACT FROM AUTHOR]

Four ruthenium(II)-based complexes with N -(acyl)- N ′, N ′-(disubstituted)thiourea derivatives (Th) were obtained. The compounds, with the general formula trans -[Ru(PPh 3 ) 2 (Th)(bipy)]PF 6 , interact with bovine serum albumin (BSA) and DNA. BSA-binding constants, which were in the range of 3.3–6.5 × 10 4 M − 1 , and the thermodynamic parameters (ΔG, ΔH and ΔS), suggest spontaneous interactions with this protein by electrostatic forces due to the positive charge of the complexes. Also, binding constant by spectrophotometric DNA titration (Kb = 0.8–1.8 × 10 4 M − 1 ) and viscosity studies indicate weak interactions between the complexes and DNA. Cytotoxicity assays against DU-145 (prostate cancer) and A549 (lung cancer) tumour cells revealed that the complexes are more active in tumour cells than in normal (L929) cells, and that they present high cytotoxicity (low IC 50 values) compared with the reference metallodrug, cisplatin. [ABSTRACT FROM AUTHOR]

In this paper we report the synthesis of the new multidentate N,O-donor ligand H 3 L_2pyald = ( N , N ′-bis-(2-pyridylmethyl)-(2-hydroxy-3-carbonyl-5-methylbenzyl)-1,3-propanediamine-2-ol) and its first trinuclear copper(II) complex, [Cu 3 (L_2pyald)( μ -OAc)](ClO 4 ) 2 ( 1 ). The structure of 1 was determined by X-ray crystallography and variable-temperature magnetic data in the temperature range of 4–300 K indicate weak antiferromagnetism ( J 1,2 ≅ −1.0 cm −1 ) between the Cu(1) and Cu(2) centers bridged by the μ -alkoxo and μ -acetate groups and weak ferromagnetic coupling ( J 1,3 = J 2,3 ≅ + 4.0 cm −1 ) involving the {Cu(1)( μ -phenoxo)Cu(3)} and {Cu(2)( μ -phenoxo)Cu(3)} structural units. Complex 1 shows significant catalytic activity towards the hydrolysis of the model substrate bis(2,4-dinitrophenyl)phosphate (2,4-BDNPP) as well as catechol oxidase activity since it efficiently catalyzes the oxidation of 3,5-di- tert -butylcatechol to 3,5-di- tert -butyl- o -benzoquinone by dioxygen. A comparison of the catalytic efficiency of 1 with its dinuclear parent complex [Cu 2 (H 2 bbppnol)( μ -OAc)] 2+ (H 3 bbppnol = N , N ′, N , N ′-bis[(2-hydroxybenzyl)(2-methylpyridyl)]-1,3-propanediamine-2-ol) reveals that the hydrolase efficiency ( k cat / K M ) is 12 times higher for 1 , while the catecholase efficiencies of these two compounds are similar. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis and characterization of the new di-iron(III) complex [(bbpmp)(H 2 O)(Cl)Fe III ( μ -O phenoxo )Fe III (H 2 O)Cl)]Cl ( 1 ), with the symmetrical ligand 2,6-bis{[(2-hydroxybenzyl)(pyridin-2-yl)methylamino]methyl}-4-methylphenol (H 3 bbpmp). Complexes 2 with the unsymmetrical ligand H 2 bpbpmp — {2-[[(2-hydroxybenzyl)(2-pyridylmethyl)]aminomethyl]-6-bis(pyridylmethyl) aminomethyl}-4-methylphenol and 3 with the ligand L 1 = 4,11-dimethyl-1,8-bis{2-[N-(di-2-pyridylmethyl)amino]ethyl}cyclam were included for comparison purposes. Complex 1 was characterized through elemental analysis, X-ray crystallography, magnetochemistry, electronic spectroscopy, electrochemistry, mass spectrometry and potentiometric titration. The magnetic data show a very weak antiferromagnetic coupling between the two iron centers of the dinuclear complex 1 ( J = − 0.29 cm − 1 ). Due to the presence of labile coordination sites in both iron centers the hydrolysis of both the diester model substrate 2,4-BDNPP and DNA was studied in detail. Complex 1 was also able to catalyze the oxidation of the substrate 3,5-di- tert -butylcatechol (3,5-DTBC) to give the corresponding quinone, and thus it can be considered as a catalytically promiscuous system. [ABSTRACT FROM AUTHOR]

Complexes with the general formula [Ru(dppb)(R) 2 ] {where: dppb = 1,4-bis(diphenylphosphino)butane and R = piperidinedithiocarbamate (pipeCS 2 − ) ( 1 ); morpholinedithiocarbamate (morphCS 2 − ) ( 2 ); ethilenodiaminedithiocarbamate (ethCS 2 − ) ( 3 ) and hexamethilenominedithiocarbamate (hexCS 2 − ) ( 4 )} were synthesised from [RuCl 2 (dppb)] 2 -μ-(dppb). The complexes were characterised by nuclear magnetic resonance of phosphorus ( 31 P{ 1 H} NMR), cyclic voltammetry (CV) as well as elemental analyses. The X-ray structures of ( 1 ), ( 2 ), and ( 3 ) were determined and are presented here. Additionally, the complexes ( 1 – 4 ) were used as pre-catalysts in the epoxidation of cyclooctene, and initial results show that complex ( 4 ) has a selectivity of 74% in the epoxide product, with 53% conversion. The epoxidation catalysed used iodosylbenzene (PhIO) as primary oxidant. [ABSTRACT FROM AUTHOR]

Abstract: The rational design of anticancer drugs is one of the most promising strategies for increasing their cytotoxicity and for minimizing their toxicity. Manipulation of the structure of ligands or of complexes represents a strategy for which is possible to modify the potential mechanism of their action against the cancer cells. Here we present the cytotoxicity of some new palladium complexes and our intention is to show the importance of non-coordinated atoms of the ligands in the cytotoxicity of the complexes. New complexes of palladium (II), with general formulae [Pd(PPh3)2(L)]PF6 or [PdCl(PPh3)(L)], where L=N,N-disubstituted-N′-acyl thioureas, were synthesized and characterized by elemental analysis, molar conductivity, melting points, IR, NMR(1H, 13C and 31P{1H}) spectroscopy. The spectroscopic data are consistent with the complexes containing an O, S chelated ligand. The structures of complexes with N,N-dimethyl-N′-benzoylthiourea, N,N-diphenyl-N′-benzoylthiourea, N,N-diethyl-N′-furoylthiourea, and N,N-diphenyl-N′-furoylthiourea were determined by X-ray crystallography, confirming the coordination of the ligands with the metal through sulfur and oxygen atoms, forming distorted square-planar structures. The N,N-disubstituted-N′-acyl thioureas and their complexes were screened with respect to their antitumor cytotoxicity against DU-145 (human prostate cancer cells), MDA-MB-231 (human breast cancer cells) and their toxicity against the L929 cell line (health cell line from mouse). [Copyright &y& Elsevier]

Abstract: The title compound, (thiosaccharine disulfide), bis[1,1′dioxide-2,3-dihidro-1,2-benzoisothiazol]disulfide, (tsac)2 has been synthesized and fully characterized by UV–Visible, IR, Raman, 1H and 13C NMR spectroscopy elemental analysis and structural X-ray crystallography. A DFT theoretical study has been performed and good agreement between experimental and theoretical values of structural parameters and vibration frequencies have been achieved. [Copyright &y& Elsevier]

Abstract: Complexes [Cu(2AcPh)Cl]·2H2O (1), [Cu(2AcpClPh)Cl]·2H2O (2), [Cu(2AcpNO2Ph)Cl] (3), [Cu(2BzPh)Cl] (4). [Cu(2BzpClPh)Cl] (5) and [Cu(2BzpNO2Ph)Cl] (6) were obtained with 2-acetylpyridine-phenylhydrazone (H2AcPh), 2-acetylpyridine-para-chloro-phenylhydrazone (H2AcpClPh), 2-acetylpyridine-para-nitro-phenylhydrazone (H2AcpNO2Ph), 2-benzoylpyridine-phenylhydrazone (H2BzPh), 2-benzoylpyridine-para-chloro-phenylhydrazone (H2BzpClPh) and 2-benzoylpyridine-para-nitro-phenylhydrazone (H2BzpNO2Ph). The hydrazones showed poor antibacterial effect against Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa but demonstrated significant antifungal activity against Candida albicans. Upon coordination to copper(II) the antibacterial and antifungal activities appreciably increased. H2AcpClPh, H2BzpClPh and their copper(II) complexes (2) and (5), respectively, were as active as fluconazole against C. albicans. [Copyright &y& Elsevier]

Abstract: 2-Acetylpyridine-phenylhydrazone (H2AcPh), its para-chlorophenylhydrazone (H2AcpClPh) and para-nitrophenylhydrazone (H2AcpNO2Ph) analogues, the corresponding 2-benzoylpyridine-derived hydrazones (H2BzPh, H2BzpClPh and H2BzpNO2Ph) and their gallium(III) complexes were assayed for their cytotoxic activity against U87 (expressing wild-type p53 protein) and T98 (expressing mutant p53 protein) glioma cells. IC50 values against both glioma cells and against the MRC5 (human fetal lung fibroblast) lineage were obtained for the hydrazones, but not for their gallium(III) complexes, due to their low solubility. Hydrazones were highly cytotoxic at nanomolar doses against U87 and T98 cells. The therapeutic indexes (TI = IC50MRC5/IC50glioma) were 2-660 for T98 cells and 28-5000 for U87 cells, indicating that the studied hydrazones could be good antitumor drug candidates to treat brain tumors. [Copyright &y& Elsevier]

Abstract: In this work we report on the synthesis, crystal structure, and physicochemical characterization of the novel dinuclear [FeIIICdII(L)(μ-OAc)2]ClO4·0.5H2O (1) complex containing the unsymmetrical ligand H2L=2-bis[{(2-pyridyl-methyl)-aminomethyl}-6-{(2-hydroxy-benzyl)-(2-pyridyl-methyl)}-aminomethyl]-4-methylphenol. Also, with this ligand, the tetranuclear [Fe2 IIIHg2 II(L)2(OH)2](ClO4)2·2CH3OH (2) and [FeIIIHgII(L)(μ-CO3)FeIIIHgII(L)](ClO4)2·H2O (3) complexes were synthesized and fully characterized. It is demonstrated that the precursor [FeIII 2HgII 2(L)2(OH)2](ClO4)2·2CH3OH (2) can be converted to (3) by the fixation of atmospheric CO2 since the crystal structure of the tetranuclear organometallic complex [FeIIIHgII(L)(μ-CO3)FeIIIHgII(L)](ClO4)2·H2O (3) with an unprecedented {FeIII(μ-Ophenoxo)2(μ-CO3)FeIII} core was obtained through X-ray crystallography. In the reaction 2 → 3 a nucleophilic attack of a FeIII-bound hydroxo group on the CO2 molecule is proposed. In addition, it is also demonstrated that complex (3) can regenerate complex (2) in aqueous/MeOH/NaOH solution. Magnetochemical studies reveal that the FeIII centers in 3 are antiferromagnetically coupled (J =−7.2cm−1) and that the FeIII–OR–FeIII angle has no noticeable influence in the exchange coupling. Phosphatase-like activity studies in the hydrolysis of the model substrate bis(2,4-dinitrophenyl) phosphate (2,4-bdnpp) by 1 and 2 show Michaelis–Menten behavior with 1 being ~2.5 times more active than 2. In combination with k H/k D isotope effects, the kinetic studies suggest a mechanism in which a terminal FeIII-bound hydroxide is the hydrolysis-initiating nucleophilic catalyst for 1 and 2. Based on the crystal structures of 1 and 3, it is assumed that the relatively long FeIII…HgII distance could be responsible for the lower catalytic effectiveness of 2. [Copyright &y& Elsevier]