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International audience; RNA-targeted drugs are considered as safe treatment option for the cure of many chronic diseases preventing off-targeted delivery and acute toxic manifestations. FDA has approved many such RNA therapies in different phases of clinical trials, validating their use for the treatment of various chronic diseases. We report herein, new water-soluble (μ-oxo) bridged polymeric Cu(II) complexes of taurine (2-aminoethane sulfonic acid) complexes 1 and 2. The therapeutic potency of 1 and 2 was ascertained by studying biophysical interactions with tRNA/ct-DNA. The experimental results demonstrated that the complexes interacted avidly to nucleic acids through intercalation mode depicting a specific preference for tRNA in comparison to ct-DNA and, moreover 2 showed higher binding propensity than 1. The electrophoretic behaviour of the complexes with plasmid pBR322 DNA and tRNA were examined by gel mobility assay that revealed a concentration-dependent activity with complex 2 performing more efficient cleavage as compared to complex 1. Cytotoxicity results on cancer cell strains displayed higher cytotoxicity than complex 1 against treated cancer cells. The synthesized copper(II) taurine complexes have met the basic criteria of anticancer drug design as they are structurally well-characterized, exhibiting good solubility in water, lipophilic in nature with superior intercalating propensity towards tRNA and cytotoxic in nature.

New cationic mixed-ligand tetranuclear complex [Cu-4(tpht) (tpmc)(2)](ClO4)(6)center dot 5H(2)O (tpmc = N, N', N '', N"'-tetrakis-(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane, H(2)tpht - terephthalic acid (benzene-1,4-dicarboxylic acid)) was prepared and characterized by elemental analysis (C, H, N, Cu), UV/Vis, IR, EPR (X-band) spectra, conductivity, cyclic voltammetry and magnetic measurements (SQUID). Five coordinated geometry for new Cu(II) complex is proposed. The central metal ion is coordinated with two pyridyl and two cyclam nitrogens and bridged with -N-(CH2)(3)-N- fragments of the cyclam ring and OCO- of the terephthalate anion. Copper (II) ions are coordinated out of cyclam rings and one OCO- group from tpht bridges two Cu(II) inside tpmc unit and two Cu(2)tpmc units are bridged by dicarboxylate tpht dianion engaging all four oxygen atoms. Weak ferromagnetic interaction between copper (II) ions in new tetranuclear complex is observed, Weiss constant theta = 0.21 K and C = 0.398 cm(3) Kmol(-1). The new complex, related Cu(II) complexes with bridged benzene carboxylate, [Cu-2(C6H5COO)tpmc](ClO4)(3)center dot CH3OH, [Cu-2(Hpht)tpmc](ClO4)(3)center dot 3H(2)O (H(2)pht = phthalic acid), [Cu-4(ipht) (tpmc)(2)](ClO4)(6)center dot NaClO4 center dot 2CH(3)CN (H(2)ipht = isophthalic acid), solvents, starting salts and ligands were in vitro evaluated for antiproliferative and antibacterial activity. Antiproliferative evaluation was carried out using tumour cell lines: HeLa (human adenocarcinoma) and K562 (chronic myelogenous leukaemia). Among all tested compounds, the ipht complex revealed the highest antiproliferative activity. According to antibacterial screening results, most active compound was the benzoate complex against Micrococcus lysodeikticus.

We report here a base free copper(I) catalyst for the selective aerobic oxidation of primary alcohols to their corresponding aldehydes and various diols to their corresponding lactones or lactols. In the presence of the in situ generated Cu(I)-catalyst with 2,2′-dipyridylamine (dpa) as a ligand and 2,2,6,6-tetramethylpiperdine-N-oxyl (TEMPO) as a persistent radical, the oxidation reaction proceeds under true aerobic conditions, at ambient temperature, utilizing air as the oxidant and without added base. High catalytic activity without over oxidation was achieved for numerous primary alcohols (aliphatic, allylic, benzylic and diols) with different substitution patterns. The catalyst's stability is unique among reported Cu(I)-catalysts. It is not moisture or air sensitive, and is capable of e.g. oxidizing aliphatic and benzyl alcohols in a water/acetonitrile solution in moderate or in quantitative yield (> 99%) in 3 h.

New cationic complexes of Cu(II) with bridged aminocarboxylates: glycine and alanine, as well as octaazamacrocyclic ligand N,N',N'',N'''-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc), with general formula [Cu2(L)tpmc](ClO4)4∙Y, (1): L=glycine, Y=2H2O and (2): L=alanine, Y=CH3CN were synthesized. Characterization of the complexes was performed by elemental analysis (C, H, N, Cu), UV/Vis, FTIR spectroscopy and magnetic measurements. The single crystal X-ray analyses results show that reported compounds were obtained as hydrates with formulae [Cu2(gly)tpmc](ClO4)4•6.5H2O (M1) and [Cu2(ala)tpmc](ClO4)4•5H2O (M2). They crystallise in the orthorhombic system, P212121 space group. The metal centres are bridged by the carboxylate group of the glycine/alanine and bound via nitrogen atoms of tmpc. In the complex M1/M2, geometry around Cu(II) coordination sphere is square pyramidal (M1 : τ5=0.10/0.33 ; M2 : τ5=0.04/0.30). In the crystal structure of M1 and M2 the amino acids exist as a zwitterion. The temperature dependence of magnetic susceptibility indicated very weak ferromagnetic interaction between two Cu(II) ions. The antiproliferative effect of the complexes, the free ligands, and cis-platin, as referent cytostatic drug, were tested against human leukemia monocytic cell line (THP-1), leukemic T cell lymphoblast (JURKAT) and Human Caucasian Burkitt′s lymphoma (RAMOS). The IC50 values for the complexes were from 37.9±2.6 to 63.05±0.72 μM.

New pyrazole derivatives were prepared and used to synthesize new bioactive agents from Cu(II) complexes that have OSN donors. Analytical and spectral (IR, UV-Vis, MS, 1H NMR, ESR & XRD) instruments characterized these complexes as well as their corresponding ligands. The bonding mode has been modified from ligand to ligand and the molar ratio for isolated complexes has also varied (1:1/1:2, M:L). The geometry of isolated complexes was commonly proposed, based on electronic transitions and ESR spectral-parameters. Via computational approaches, these structures were optimized using standard programs (Gaussian 09 & HyperChem 8.1) under the required basis set. Consequently, important physical characteristics have been obtained after finishing the optimization process. Inhibition behavior of all new synthesizes was studied by MOE module as in-silico approach which conducted versus the crystal structure of NUDT5 protein (6gru) of breast cancer cells. The interaction features summarized from docking processes, reveal effective inhibition validity for new Cu(II) complexes versus breast cancer cells. This according to scoring energy values and the stability of docking complexes in true interaction path (bond length ≤3.5 A) particularly with Cu(II)-L3 and Cu(II)-L4 complexes. This reflects the possibility of successful behavior during practical application through in-vitro assay that intended in this study. Finally, the degree of toxicity of such new compounds to the breast cancer cell line was determined by in-vitro screening. To judge perfectly on their toxicity, in-vitro screening must compared to positive control as Doxorubicin (reference drug). IC50 values were calculated and represent Cu(II) complexes as outstanding cytotoxic agents which revealed superiority on the reference drug itself.

A tetranuclear Cu(II) cubane [Cu2(μ-1κONO’:2κOO’:3κO-HL)(μ-1κONO’:2κOO’-HL)]2‧4dmf (1) derived form (2,3-dihydroxybenzylidene)-2-hydroxybenzohydrazide (H3L) was synthesized at room temperature and characterized by elemental analysis, IR spectroscopy, ESI-MS and single crystal X-ray diffraction. The known tetranuclear Cu(II) open-cubane [Cu(HL)]4‧4EtOH (2) was synthesized from the same pro-ligand following a similar method or the reported one. The different tautomeric forms (keto and enol) of the organic ligands in 1 and 2 explain their different structural features. Both complexes were screened as catalysts for the peroxidative oxidation of toluene with tert-butyl hydroperoxide, achieving benzaldehyde and o-cresol as the main products. Complex 1 exhibits the highest activity (maximum product yield of 11%).

International audience; Design of simple-component theranostic agents with enhanced tumor accumulation represents a novel strategy in the area of precision nanomedicine for effective tumor theranostics. Herein, we report an innovative theranostic strategy based on ultrasound-enhanced tumor accumulation of a theranostic agent of phosphorus dendrimer-copper(II) complexes (1G3-Cu). The employed 1G3-Cu complexes represent a drug-free nanotheranostic agent with a simple composition possessing an r1 relaxivity of 0.7024 mM−1 s−1 for T1-weighted magnetic resonance (MR) imaging and an IC50 of 1.24 μM to inhibit the growth of a pancreatic cancer cell line. We show that cancer cells can be inhibited by the 1G3-Cu complexes through the activation of the apoptotic process with the upregulation of Bax, P53 and PTEN, downregulation of Bcl-2, and decrease of intracellular ATP. With the assistance of ultrasound targeted microbubble destruction (UTMD) technology that can increase cell membrane permeability temporarily via sonoporation effect, the 1G3-Cu complexes enable enhanced tumor MR imaging and chemotherapy due to their improved tumor accumulation. With the proven minimal toxicity to normal tissues at imaging and therapeutic doses, the prepared 1G3-Cu complexes may be potentially employed for UTMD-enhanced theranostics of different types of cancer.

WOS: 000355041400001, The tridentate (NNO) Schiff base (HL), has been prepared by the condensation of 2-(aminomethyl)pyridine with 5-chloro-salicylaldehyde. The mononuclear [N-(2-pyridylmethyl)-3-chloro-salicylaldiminato] (azido) copper(II) complex of general formula [Cu(L)(N-3)] (1) has been synthesized by the treatment of HL and CuCl2 center dot 2H(2)O with sodium azide. The ligand and complex have been investigated by various methods including IR, TG-DTA and X-ray diffraction techniques. The complex crystallizes in monoclinic space group P2(1/c), with unit cell dimensions a = 6.7369(4), b = 11.6058(8), c = 17.1379(11) angstrom, beta = 93.823(2)degrees. The distorted square-planar Cu(II) ion in complex is chelated by one imino N, one phenolic O and one pyridine N atoms of Schiff base ligand and one N atom of azide ion. The electrochemical behavior of the mononuclear copper azido complex was studied with cyclic voltammetry. Tautomer stability of the ligand and the complex has been determined by molecular modeling techniques. It has been concluded that the HL is more stable than its tautomeric form (THL) both as ligand and complex structures, Scientific Research Council of Balikesir University [2010/30], The financial support of Scientific Research Council of Balikesir University (Project No. 2010/30) is gratefully acknowledged.

Two new coordination compounds [Fe(bib)2(N3)2]n (1) and [Cu2(bpp)2(N3)4] (2) with azide and flexible ligands 1,4-bis(imidazolyl)butane (bib) and 1,3-bis(3,5-dimethylpyrazolyl)propane (bpp) were prepared and structurally characterized. In the 2D network structure of 1, the iron(II) ion lies on an inversion center and exhibits an FeN6 octahedral arrangement while in the dinuclear structure of 2, the copper(II) ion adopts an FeN5 distorted square pyramid geometry. In the complex 1, each μ2-bib acts as bridging ligand connecting two adjacent iron(II) ions while in the complex 2, the bpp ligand is coordinated to copper(II) ion in a cyclic-bidentate fashion forming an eight-membered metallocyclic ring. Coordination compounds 1 and 2 have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. Thermal analysis of polymer 1 was also studied.

Some copper(I) complexes of the type [Cu(L)(dppe)]X (1-4) [where L = (3-trifluoromethylphenyl)pyridine-2-ylmethylene-amine; dppe = 1,2-bis(diphenylphosphino) ethane; X = Cl, CN, ClO(4) and BF(4)] have been synthesized by the condensation of 3-aminobenzotrifluoride with 2-pyridinecarboxaldehyde followed by the reaction with CuCl, CuCN, [Cu(MeCN)(4)] ClO(4) and [Cu(MeCN)(4)] BF(4) in presence of dppe. The complexes 1-4 were then characterized on the basis of elemental analysis, IR, UV-Vis and (1)H NMR spectral studies. The representative complex of the series 4 has been characterized by single crystal X-ray diffraction which reveal that in complex the central copper(I) ion assumes the irregular pseudo-tetrahedral geometry. The catalytic activity of the complexes was tested and it was found that all the complexes worked as effective catalyst in the amination of aryl halide. .

Four new square-planar Ni(II) and Cu(II) complexes with [N2O2] binding system were synthesized by metal-directed condensation of 2,6-diformyl-4-methylphenol with benzoyl or acetylacetone mono-S-methylisothiosemicarbazone. Only mononuclear “one-armed” complexes were obtained as a consequence of the different reactivity of the two carbonyl groups in the hydroxydialdehyde. The complexes were characterized by elemental analysis, EI MS and UV–Vis spectroscopy. The structural assignment was confirmed by X-ray diffraction analysis and NMR spectroscopy, for the Ni(II) complexes, and by ESR spectroscopy and magnetic measurements, for the Cu(II) complexes.