Cluster dirhenium(III) cis-dicarboxylates with α-amino acids ligands as mighty selective G4s binders.

The synthesis of four dirhenium(III) cis-dicarboxylates with the α-amino acids residues Asp (I), Glu (II), Phe (III) and Tyr (IV) is presented. The G-quadruplex stabilization potential was evaluated by fluorescence resonance energy transfer - melting analysis. All derivatives show specific binding to c-kit1 quadruplex, while II and IV have also strong stabilization activity to HTelo21 quadruplex.

Encapsulation of Dirhenium(III) Carboxylates into Zirconium Phosphate.

Present work reports the synthesis of zirconium phosphate nanoparticles containing dirhenium(III) substance bis-dimethylsulfoxide-cis-tetrachlorodi-?-pivalatodirhenium(III) with formula cis-Re2(C(CH3)3COO)2Cl4?2DMSO (I) and q-zirconium phosphate with formula q-Zr(HPO4)2?6H2O (ZrP). The intercalation process was monitored by EAS. Due to the spectral characteristics of the quadruple bond the conclusion was made that the obtained intercalated compounds had cis-configuration of ligands around cluster dirhenium fragment.

Supramolecular networks supported by the anion...π linkage of Keggin-type heteropolyoxotungstates.

Anion...

Tuning the structure of aminoferrocene-based anticancer prodrugs to prevent their aggregation in aqueous solution.

Aminoferrocene-based prodrugs are activated in cancer cells by reactive oxygen species (ROS). They were shown to exhibit high cytotoxicity towards a variety of cancer cell lines and primary cancer cells, but remain not toxic towards non-malignant cells. However, these prodrugs have rather high lipophilicity leading to relatively low water solubility.

Crystal structure of bromido--tricarbon-yl[5-(3,4,5-tri-meth-oxy-phen-yl)-3-(pyridin-2-yl)-1-1,2,4-triazole-κ,]rhenium(I) methanol monosolvate.

In the title compound, [ReBr(CHNO)(CO)]·CHOH, the Re atom adopts a distorted octa-hedral coordination sphere with a facial arrangement of the three carbonyl ligands. Two N atoms of the chelating 5-(3,4,5-tri-meth-oxy-phen-yl)-3-(pyridin-2-yl)-1-1,2,4-triazole ligand and two carbonyl ligands define the equatorial plane of the complex, with the third carbonyl ligand and the bromide ligand in axial positions. Conventional hydrogen bonds including the methanol solvent mol-ecules assemble the complex mol-ecules through mutual N-H⋯O-H⋯Br links [N⋯O = 2.

Crystal structure of fac-aquatricarbonyl[(S)-valin-ato-κ(2) N,O]-rhenium(I).

In the mol-ecule of the title compound, [Re(C5H10NO2)(CO)3(H2O)], the Re(I) atom adopts a distorted octa-hedral coordination sphere defined by one aqua and three carbonyl ligands as well as one amino N and one carboxyl-ate O atom of the chelating valinate anion. The carbonyl ligands are arranged in a fac-configuration around the Re(I) ion. In the crystal, an intricate hydrogen-bonding system under participation of two O-H, two N-H and one C-H donor groups and the carboxyl-ate and carbonyl O atoms as acceptor groups contribute to the formation of a three-dimensional supra-molecular network.

Crystal structure of bis-(ethyl-enedi-thio)-tetra-thia-fulvalenium μ2-acetato-bis-[tri-bromido-rhenate(III)] 1,1,2-tri-chloro-ethane hemisolvate.

The asymmetric unit of the title salt, (C10H8S8)[Re2Br6(CH3COO)]·0.5C2H3Cl3, contains one bis-(ethyl-enedi-thio)-tetra-thia-fulvalene (ET) radical cation, one μ2-acetato-bis-[tri-bromido-rhenate(III)] anion and a 1,1,2-tri-chloro-ethane mol-ecule with half-occupancy disordered about a twofold rotation axis. The tetra-thia-fulvalene fragment adopts an almost planar configuration typical of the ET radical cation.

Crystal structure of di-μ-isobutyrato-κ(4) O:O'-bis-[cis-di-chlorido-(dimethyl sulfoxide-κS)rhenium(III)].

The title compound, [Re2(C3H7COO)2Cl4{(CH3)2SO}2], comprises binuclear complex mol-ecules [Re-Re = 2.24502 (13) Å] involving cis-oriented double carboxyl-ate bridges, four equatorial chloride ions and two weakly bonded O atoms from dimethyl sulfoxide ligands in the axial positions at the Re(III) atoms. In the crystal, mol-ecules are linked into corrugated layers parallel to (101) by very weak C-H⋯Cl and C-H⋯O hydrogen-bonding inter-actions.

Synthesis and X-ray crystal structure of the dirhenium complex Re2(i-C3H7COO)4Cl2 and its interactions with the DNA purine nucleobases.

The dirhenium complex Re2(i-C3H7COO)4Cl2 was synthesized and characterized by X-ray crystallography, (1)H NMR and electronic spectroscopies, and electrospray ionization-mass spectrometry. The reactions of Re2(i-C3H7COO)4Cl2 with the substituted DNA purine nucleobases guanine (9-methylguanine and 9-ethylguanine) and adenine (9-methyladenine and 9-ethyladenine) were investigated by proton nuclear magnetic resonance and electronic spectroscopies as well as electrospray ionization-mass spectrometry. The data corroborate binding of two 9-methylguanine (or 9-ethylguanine) and 9-methyladenine (or 9-ethyladenine) bases per dirhenium unit in a bidentate fashion, in equatorial positions, via sites N7/O6 and N1/N6, respectively, with concomitant substitution of two carboxylate groups to form a single isomer of cis-Re2(i-C3H7COO)2(nucleobase)2Cl2.

Crystal structure of cis-bis-(μ-β-alanine-κ(2) O:O')bis[tri-chlorido-rhenium(III)](Re-Re) sesquihydrate.

The structure of the title compound, [Re2Cl6(C3H7NO2)2]·1.5H2O, comprises a dinuclear complex cation [Re-Re = 2.2494 (3) Å] involving cis-oriented double carboxyl-ate bridges, four equatorial chloride ions and two weakly bonded chloride ligands in the axial positions at the two rhenium(III) atoms.

Crystal structure of bromido-fac-tricarbon-yl[5-phenyl-3-(pyridin-2-yl)-1H-1,2,4-triazole-κ(2) N,N']rhenium(I).

In the title compound, [ReBr(C13H10N4)(CO)3], the Re(I) atom has a distorted octa-hedral coordination environment. Two N atoms of the 5-phenyl-3-(pyridin-2-yl)-1H-1,2,4-triazole ligand and two of the three carbonyl groups occupy the equatorial plane of the complex, with the third carbonyl ligand and the bromide ligand in the axial positions. The three carbonyl ligands are arranged in a fac configuration around the Re(I) atom.

Liposomes loaded with a dirhenium compound and cisplatin: preparation, properties and improved in vivo anticancer activity.

Liposomes loaded with the rhenium compound (bis-dimethylsulfoxido-cis-tetrachlorodi-μ-pivalatodirhenium(III) (cis-Re2((CH3)3CCOO)2Cl4.2DMSO, I) and cisplatin in the molar ratio of 4:1 as well as those loaded only with I were synthesized and characterized by scanning electron microscopy, transmission electron microscopy, dynamic light scattering and electronic absorption spectroscopy. The relative stability of liposomes loaded with I is reflected by a minimal change in the electronic absorption spectra over a period of 8 days whereas the stability of those loaded with both drugs is lower, which we ascribe to the formation of new Re-Pt species inside the liposomes.

Synthesis, X-ray structure, interactions with DNA, remarkable in vivo tumor growth suppression and nephroprotective activity of cis-tetrachloro-dipivalato dirhenium(III).

In this study we report the synthesis, the X-ray crystal structure and the in vivo tumor growth suppression and nephroprotective activity of bis-dimethylsulfoxide-cis-tetrachlorodi-μ-pivalatodirhenium(III), cis-Re2[(CH3)3CCOO]2Cl4·2(CH3)2SO (I). The interactions of I with DNA were also investigated by electrophoretic mobility shift assays, electronic absorption titrations, ΔTm and viscosity measurements, which indicate that compound I interacts relatively strongly with the DNA (Kb 2.2×10(3)M(-1)), most likely by forming covalent interstrand cross-links, and by kinking and unwinding supercoiled DNA; moreover, DNA cleavage by I is enhanced in the presence of redox-active species.

Sequential insertion of three different organometallics into a versatile building block containing a PNA backbone.

In the view of developing a synthetic route for the controlled insertion of distinct organometallic moieties into peptide nucleic acid (PNA) oligomers, a proof-of-principle study of the chemoselective insertion of three different organometallics into a building block containing both a PNA backbone and an alkyne side-chain is presented in this study.

Synthesis, characterization, in vivo antitumor properties of the cluster rhenium compound with GABA ligands and its synergism with cisplatin.

A new dirhenium(III) complex cis-[Re2(GABA)2Cl5(H2O)]Cl.2H2O with zwitterionic gamma-aminobutyrate ligands was prepared and characterized by spectral methods and crystallography. The structure of the compound is comprised of dinuclear complex cations (Re-Re 2.

Liposomal forms of rhenium cluster compounds: enhancement of biological activity.

Liposomal formulations of dinuclear cluster rhenium (Re) compounds were used in biochemical trials. Interaction of liposomal forms of some Re compounds with red blood cells in experiments in vitro showed strong cell-stabilizing properties. In the models of tumor growth and hemolytic anemia in vivo, liposomal forms had better therapeutic effects in comparison with their solutions.

Dichlorotetra-mu-Isobutyratodirhenium(III): enhancement of cisplatin action and RBC-stabilizing properties.

Background: Previous investigations showed antitumor properties of dirhenium carboxylate introduced to tumor-bearing animals at high doses. The development of liposomal forms of rhenium substances and the activity of dichlorotetra-mu-isobutyratodirhenium (III) (Re1) in stabilizing red blood cells (RBC) shown in experiments in vitro and in vivo enabled the use of this substance in the present study. The aim of the work was to investigate the antitumor properties of Re1 in liposomal form alone and together with cisplatin, and to analyze whether Re1 can support RBC in the model of tumor growth.