A 3D Mesomeric Supramolecular Structure of a Cu(II) Coordination Polymer with 1,1′-Biphenyl-2,2′,3,3′-tetracarboxylic Acid and 5,5′-Dimethyl-2,2′-bipyridine Ligands

A novel metal–organic framework {[Cu(H₂bptc)(cbpy)(H₂O)]·(H₂O)} _n (1) has been hydrothermally synthesized through reaction of 1,1′-biphenyl-2,2′,3,3′-tetracarboxylic acid (H₄bptc) with Cu(II) salt in the presence of ancillary nitrogen ligand 5,5′-dimethyl-2,2′-bipyridine (cbpy), and its structure was determined by X-ray diffraction and characterized by elemental analysis, and IR spectrum. The title compound crystallizes in monoclinic space group P2₁/c. Both right- and left-handed helices are detected in the structure. In the ab-plane, adjacent chains are homochiral and parallel to each other, which are connected together by hydrogen bonds to form a 2D supramolecular structure. The supramolecular layers with opposite chirality are arranged alternatively along the c-axis to form a 3D mesomeric supramolecular structure through π···π interactions. The thermal stability of the complex 1 was studied by thermal gravimetric and differential thermal analysis.     

Carbonyl and chloro complexes of ruthenium(II) containing 3,3′-diester-2,2′-bipyridyl ligands

A series of 3,3′-dialkoxycarbonyl-2,2′-bipyridines (alkyl=Me, Et, i-Pr, i-Bu) has been prepared in good yield from 1,10-phenanthroline. The synthesis and characterization of the corresponding trans-(Cl)-Ru(L)(CO)₂Cl₂ and cis-Ru(L)₂Cl₂ complexes are described.     

Electrochemical Synthesis of Cu (II) Coordination Polymer Coatings Based on 2,2′-Thiodiacetic Acid and 1,2,4,5-Benzenetetracarboxylate

Electrochemical synthesis of coordination polymers of Cu(II), [Cu(TDA)]_n and [Cu₂(BTC)(H₂O)₆?6H₂O]_n in which H₂TDA is 2,2′-thiodiacetic acid and BTC stands for 1,2,4,5-benzenetetracarboxylate was carried out by the electrochemical oxidation of Cu anode in the presence of H₂TDA (a flexible ligand), and 1,2,4,5-benzentetracarboxylic acid (H₄BTC) (a rigid ligand) in aqueous solutions. The structure of coordination polymers were characterized by scanning electron microscopy, X-ray powder diffraction, elemental analysis, thermal gravimetric and differential thermal analyses. The crystal structure of the compounds consists of one-dimensional cubical crystal polymeric units of [Cu(TDA)]_n and [Cu₂(BTC)(H₂O)₆?6H₂O]_n. Furthermore, the coordination number of Cu (II) ions in synthesized coordination polymers to be found five. The main advantages of electrosynthesis are the minor synthesis time, the milder conditions and the facile synthesis of coordination polymer coatings.     

Synthesis,Characterization, and in vivo Distribution of Intracellular Delivered Macrolide Short-Chain Fatty Acid Derivatives

Short-chain fatty acids (SCFAs) have a range of effects in metabolism and immune regulation. We have observed that delivery of SCFAs to lysosomes has potent immune regulatory effects, possibly as a surrogate signal for the presence of anaerobic organisms. To better understand the pharmacology of lysosomal SCFA donors, we investigated the distribution and metabolism of propionate and butyrate donors. Each analog ( 1 a and 2 a ) can donate three SCFA equivalents via ester hydrolysis through six intermediate metabolites. The compounds are stabilized by low pH, and stability in cells is usually higher than in medium, but is cell-type specific. Butyrate derivatives were found to be more stable than propionates. Tri-esters were more stable than di- or mono-esters. The donors were surprisingly stable in vivo, and hydrolysis of each position was organ specific. Jejunum and liver caused rapid loss of 4’’ esters. The gut metabolite pattern by i. v. differed from that of p.o. application, suggesting luminal and apical enzyme effects in the gut epithelium. Central organs could de-esterify the 11-position. Levels in lung relative to other organs were higher by p.o. than via i. v., suggesting that delivery route can influence the observed pharmacology and that gut metabolites distribute differently. The donors were largely eliminated by 24 h, following near linear decline in organs. The observed levels and distribution were found to be consistent with pharmacodynamic effects, particularly in the gut.     

Synthesis and properties of poly(ester imide) copolymers from 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,2′-bis(trifluoromethyl)benzidine,and 4-aminophenyl-4′-aminobenzoate

A series of poly(ester imide) (PEsI) copolymers were synthesized using 3,3′,4,4′-biphenyltetracarboxylic dianhydride (4,4′-BPDA), 2,2′-bis(trifluoromethyl)benzidine (TFMB), and 4-aminophenyl-4′-aminobenzoate (APAB) as the monomers. Wide-angle x-ray diffraction results revealed that the average interchain distances of these polymers ranged from 4.6 to 5.7 Å, increasing with the increase of TFMB contents. PEsI-0.3 and PEsI-0.4 exhibited a glass transition temperature (T_g) of 445 and 455°C, respectively, while no distinctive T_g was observed for the PEsI copolymers when the APAB content was >50 mol%. The coefficients of thermal expansion (CTE) of these PEsI copolymers ranged from 3.8 to 24.2 ppm K⁻¹, increasing with the increase of TFMB contents. The PEsI copolymers exhibited a modulus of 5.7–7.8 GPa, a tensile strength of 282–332 MPa, and an elongation-at-break of 10.2%–23.3%. Furthermore, these copolymers exhibited a dielectric constant of 2.53–2.76, and a low dissipation factor (D_f) of 0.0026–0.0032 at 10 GHz in dry state. Because of their excellent combined properties, these PEsI copolymers are promising candidates as dielectric substrate materials for the applications in next generation flexible printed circuit boards operating at high frequencies.     

Synthesis and Characterization of Mesostructured Silica Doped with Acyl‐Hydroxy‐Pyrazole Derivatives. Sorption Tests of Cu(II) and Eu(III)

Abstract

The synthesis and the characterization of mesostructured silica doped with acidic acyl‐hydroxy‐pyrazoles like extractants are described. The extractants have either a single chelating site, 1‐phenyl‐3‐methyl‐4‐stearoyl‐5‐hydroxy‐pyrazole (HPMSP), or two chelating sites, 1,12‐bis(1′‐phenyl‐3′‐methyl‐5′‐hydroxy‐4′‐pyrazolyl)‐dodecane‐1,12‐dione (HL‐10‐LH). The so‐called doped silicas were synthesized in basic medium according to a sol‐gel process beginning with the solubilization of the extractant in a micellar phase followed by the precipitation of silica around micelles. The chemical composition of the synthesized materials, especially the ligand content, was determined. High quantities of ligand loadings (up to 0.69 mol/kg) are reached. The materials obtained were characterized by X‐ray diffraction, laser granulometry, transmission and scanning electron microscopy and, after calcination, by nitrogen physisorption. Un‐doped silica is mesostructured, lamellar, and has high pore diameter as well as high specific surfaces. Doping induces the disorganization of the lamellar structure, the increase of the pore diameter, and a slight decrease of the specific surface. The capacities of extraction of Cu(II) and Eu(III) by the doped materials and the corresponding extraction rate were measured: high values are reached.     

Synthesis of soluble polyarylenes containing alternating 4,4′-(1,1′-binaphthyl) and 4,4′-(3,3′-diphenyl)biphenyl structural units

Summary The synthesis and Ni(0) catalyzed homocoupling polymerization of 4,4-bis[5-(trifluoromethanesulfonyloxy)-2-biphenylyl]-1, 1-binaphthyl (9) are described. This polymerization reaction produces a soluble polyarylene containing alternating 4,4-(1,1-binaphthyl) and 4,4-(3,3-diphenyl)biphenyl structural units.     

Synthesis and Biological Evaluation of CF3Se-Substituted α-Amino Acid Derivatives

Several CF₃Se-substituted α-amino acid derivatives, such as (R)-2-amino-3-((trifluoromethyl)selanyl)propanoates ( 5 a / 6 a ), (S)-2-amino-4-((trifluoromethyl)selanyl)butanoates ( 5 b / 6 b ), (2R,3R)-2-amino-3-((trifluoromethyl)selanyl)butanoates ( 5 c / 6 c ), (R)-2-((S)-2-amino-3-phenylpropanamido)-3-((trifluoromethyl)selanyl)propanoates ( 11 a / 12 a ), and (R)-2-(2-aminoacetamido)-3-((trifluoromethyl)selanyl)propanoates ( 11 b / 12 b ), were readily synthesized from natural amino acids and [Me₄N][SeCF₃]. The primary in vitro cytotoxicity assays revealed that compounds 6 a , 11 a and 12 a were more effective cell growth inhibitors than the other tested CF₃Se-substituted derivatives towards MCF-7, HCT116, and SK-OV-3 cells, with their IC₅₀ values being less than 10 μM for MCF-7 and HCT116 cells. This study indicated the potentials of CF₃Se moiety as a pharmaceutically relevant group in the design and synthesis of novel biologically active molecules.     

A convenient method for synthesis of bis-2,2′-(1,3,4-thiadiazole) and bis-3,3′-(1,2,4-triazole) derivatives

Reactions of the bis-hydrazonoyl chloride 1 with ketene N,S-acetal 2 and the active methine thioanilides 4 and 6 provide a new convenient site-selective synthetic strategy to functionalized bis-3,3′-(1,2,4-triazoles) 3 and bis-2,2′-(1,2,4-thiadiazoles) 5 and 7.     

Synthesis, Structures and Luminescent Properties of Two New Cd(II) Coordination Polymers Based on V-Shaped 3,3′,4,4′-Oxidiphthalic Acid

Two new Cd(II) coordination polymers, namely [Cd₂(H₂OA)₂(μ₂-H₂O)(H₂O)₆] _n ·3nH₂O (1) and [Cd₂(H₂OA)(phen)₂] _n ·nH₂O (2) (H₄OA = 3,3′,4,4′-oxidiphthalic acid, phen = 1,10-phenanthroline) have been synthesized by combining H₄OA or H₄OA and phen with Cd(II) salts under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals that 1 features a hydrogen-bond directed two-dimensional (2D) layered structure constructed from alternating left- and right-handed double strand helical chains, 2 represents a one-dimensional (1D) chain structure with the phen molecules dangling on it, which is further extended into a three-dimensional (3D) supramolecular framework through strong face-to-face π···π interactions. In addition, luminescent properties of these two compounds were also investigated in the solid state at room temperature.     

One-Dimensional Cd(II) and Co(II) Coordination Polymers with Dinuclear Secondary Building Units Constructed by 1,1′-Biphenyl-3,3′-Dicarboxylic Acid: Synthesis, Structures, Luminescent and Magnetic Properties

Bilayered diffusion and hydrothermal synthetic methods using pyridine (py) and 2,6-dimethylpyrazine (dmpz) as weak bases and small terminal ligands generated two Cd(II) and Co(II) 1D coordination polymers with dinuclear metal clusters as secondary building units (SBUs) from an organic bridging ligand, 1,1′-biphenyl-3,3′-dicarboxylic acid (H₂ L). They are {[Cd₂(L)₂(py)₄] (py)(CH₃OH)} _n (1) and [Co₂(L)₂(dmpz)₄(H₂O)] _n (2). Compounds 1 crystallizes in the monoclinic space group P2(1)/c, while 2 crystallizes in the triclinic space group P-1. Especially, compound 2 possesses the 1D chain structure that contains two linked left-handed and right-handed helices. Fluorescent measurements for 1 display strong blue light emissions with the maximum emission at 396 nm with the excitation of 320 nm. Magnetization study shows the existence of weak antiferromagnetic coupling for 1 with the negative −E ₂/k value of −1.3 K.     

Design,Synthesis and Bioactivity of N-Glycosyl-N′-(5-substituted phenyl-2-furoyl) Hydrazide Derivatives

Condensation products of 5-substituted phenyl-2-furoyl hydrazide with different monosaccharides d-glucose, d-galactose,d-mannose, d-fucose and d-arabinose were prepared. The anomerization and cyclic-acyclic isomers were investigated by ¹H NMR spectroscopy. The results showed that, except for the d-glucose derivatives, which were in the presence of β-anomeric forms, all derivatives were in an acyclic Schiff base form. Their antifungal and antitumor activities were studied. The bioassay results indicated that some title compounds showed superior effects over the commercial positive controls.     

Synthesis, Structure and Luminescence Property of Cadmium(II) Coordination Polymer with Mixed 5-(Oxidediphenylphosphino)isophthalic Acid and 4,4′-Bipyridine Ligands

A new metal–organic framework {[Cd(L)(4,4′-bpy)]₂·5H₂O} _n (1) had been synthesized by hydrothermal reaction of 5-(oxidediphenylphosphino)isophthalic acid, Cd(II) nitrate, NaOH and 4,4′-bipyridine (4,4′-bpy) as co-ligand. The novel compound was characterized by single crystal X-ray diffractometry as well as FTIR spectrum. Adjacent eight-member (C₂Cd₂O₄) rings are connected each other through pairs of L^2? ligands to result in a 1D double chain. Such ribbons are interconnected together by 4,4′-bpy to generate a 2D pillared layer, which are further held together by rich O–H···O hydrogen bonds to give a 3D supramolecular network. Solvent water molecules play an important role to bridge adjacent layers to form a 3D supramolecular architecture. The luminescence property and thermogravimetric analysis of title complex were investigated.     

Green Synthesis,Structural Characterization and Photocatalytic Activities of Chitosan-ZnO Nano‐composite

Journal of Inorganic and Organometallic Polymers and Materials - Chitosan was isolated from chitin, a direct derivative of snail shell, and further used to form a heterostructure with ZnO...     

Entry to alkynylplatinum(IV) chemistry using hypervalent iodine(III) reagents,and the synthesis of triphenyl{4,4′-bis(tert-butyl)-2,2′-bipyridine}iodoplatinum(IV)

The reaction of phenyl(alkynyl)iodine(III) triflates with diorganoplatinum(II) complexes provides a general route for the synthesis of a new class of alkynylplatinum(IV) complexes containing Pt^IVR₂(CCR²) groups, e.g., the 4,4^′-bis(tert-butyl)-2,2^′-bipyridine complexes PtIR₂(CCSiMe₃)(Bu^t₂bpy) (R=Me, Ph); IPh₂(OTf) reacts with PtPh₂(Bu^t₂bpy) to form the first archetypal triarylplatinum(IV) complex PtIPh₃(Bu^t₂bpy).     

Syntheses and Characterization of Two New M(II)-5,5′-dimethyl-2,2′-bipyridine (M = Cd and Pb) Coordination Polymers and Study of Their Thermal and Electrochemical Properties

Two new cadmium(II) and lead(II)-thiocyanato coordination polymers with 5,5′-dimethyl-2,2′-bipyridine (5,5′-dm-2,2′-bpy) as chelating ligands were synthesized and characterized by elemental analysis, IR and ¹H NMR spectroscopy and by X-ray crystallography. Thermal and electrochemical properties were also studied as well. These complexes have formed formula [Cd(5,5′-dm-2,2′-bpy)(NCS)₂]_n (1) and [Pb(5,5′-dm-2,2′-bpy)(CH₃COO)(NCS)]_n (2). The coordination numbers of Cd^II in 1 and Pb^II in 2 are six (CdN₄S₂) and seven (PbN₃O₃S₂), respectively. In 2, “stereo-chemically active” electron lone pairs and the coordination spheres were hemidirected. Bridging properties of thiocyanato anions in 1 and 2 created one- and two-dimensional coordination polymers, respectively. The supramolecular features in these complexes were guided and controlled by weak directional intermolecular interactions.     

Synthesis and Structural Studies of PdII/ZnII Architecture with N,N′-Bis(2-hydroxyethyl)ethylenediamine as Capping Ligand

A new compound of the composition [-{Zn-di-μ-bishydeten(O)-Zn}-μ-(CN)₂Pd(CN)₂] (1) was obtained from the reaction of PdCl₂, bishydeten [N,N′-bis(2-hydroxyethyl)ethylenediamine], KCN and ZnCl₂ in water/ethanol mixture. This dimeric polymer was characterized by IR spectroscopy and elemental analysis, and its thermal properties were studied by TG and DTG. In addition, the crystal structure was determined by single-crystal X-ray analysis. IR spectroscopy pointed out the existence of both terminal and bridged cyano ligands in the complex structure. When it comes to thermal analysis, the complex followed usual decomposition mechanism in which neutral ligands are decomposed first and then anionic ligands left the structure. Single crystal X-ray analysis revealed that 1 exhibited polymeric structure. An interesting feature of this complex is that ancillary bishydeten ligand acted as a bridge just like cyano groups did. In the complex structure, dimeric Zn units, which were gathered by –O atoms of bishydeten ligands in an asymmetric fashion, were bridged by tetracyanopalladate^II anions. 1D chain turned into 3D chains by means of intermolecular hydrogen bonds.     

New Diamides of 2,2′-dipyridyl-6,6′-dicarboxylic Acid for Actinide-Lanthanide Separation

The extraction of americium and lanthanides by diamides of 2,2′-dipyridyl-6,6′-dicarboxilic acid solutions in polar diluents was investigated. The dependence of extraction properties of the diamides on their structure was studied and the distribution ratios of americium and lanthanides from nitric acid solutions were determined. The highest extraction was found for the compounds with the ethyl-group and the alkyl-substituted aryl-group on the amidic nitrogen. The Am/Ln separation factors higher than 10 were achieved for extraction from high acidity media.