Synthesis,crystal structures and antimicrobial activity of azido and isocyanato Zn(II) complexes with the condensation product of 2-quinolinecarboxaldehyde and Girard’s T reagent

Two Zn(II) complexes with the condensation product of 2-quinolinecarboxaldehyde and trimethylammonium acetohydrazide chloride (Girard’s T reagent) (HLCl) and monodentate pseudohalides (azide and cyanate) have been synthesized and characterized by elemental analysis, IR and NMR spectroscopy, and single-crystal X-ray diffraction. In both complexes, the coordination surroundings of the Zn(II) ions consist of a deprotonated hydrazone ligand coordinated through an NNO set of donor atoms and two monodentate pseudohalides (N₃^– or NCO^–) at the remaining coordination sites. The Zn(II) complexes showed low to moderate activity against laboratory control strains of pathogenic bacteria and fungi.     

Bare Particulars Laid Bare

Bare particulars have received a fair amount of bad press. Many find such entities to be obviously incoherent and dismiss them without much consideration. Proponents of bare particulars, on their part, have not done enough to clearly motivate and characterize bare particulars, thus leaving them open to misinterpretations. With this paper, I try to remedy this situation. I put forward a much-needed positive case for bare particulars through the four problems that they can be seen to solve—The Problem of Individuation, The Problem of Change, The Problem of Having a Property, and The Problem of Subtraction. I then distinguish and characterize three possible types of bare particulars—genuinely bare, constitutively bare, and thinly clothed—and consider how each of these cope with some classical and recent objections to bare particulars. I argue that the most troubling objections do not come from familiar quarters, but from examining how well such entities address all four of the ontological problems outlined. I ultimately conclude that the best contenders among the three types of bare particulars are the constitutively bare variety, but argue that, if they are to earn their keep, they must either share or turn over their individuating role to the ordinary particulars that they constitute.     

Determination of Nitrates in Water Samples by In‐Electrode Coulometric Titration in Copper Coated Porous Vitreous Carbon Electrode

Nitrate in water samples was determined by in‐electrode coulometric titration in porous electrode made of vitreous carbon particles coated with copper. The sample was mixed with diluted sulfuric acid containing 1 mmol/L hydrochloric acid, the solution was filled into the cell and electrode and the nitrate ions were directly reduced by constant current to ammonium ions. The stoichiometry of the electrode reaction was found by coulometric and photometric measurements. The detection limit and precision were found to be 0.2 mg/L and 1.7 %, respectively. The interfering effect of high chloride contents was eliminated by precipitating chlorides with silver sulfate. The method was applied for the analysis of various water samples and beverages. The results were in good agreement with data from isotachophoretic and photometric measurements.     

Alcohols immobilization onto 2-chlorotritylchloride resin under microwave irradiation

The immobilization of alcohols onto 2-chlorotritylchloride resin using microwave irradiation was studied. Three different Fmoc-aminoalcohols were tested: the phenol-like Fmoc-tyramine, the primary alcohol Fmoc-ethanolamine, and the secondary alcohol Fmoc-4-hydroxypiperidine. Several reaction conditions were evaluated: different bases, reaction times, temperatures, and concentrations. Microwave immobilization resulted is effective in binding to the resin all three types of alcohols with loadings which were superior or comparable to the ‘classical’ methods in shorter time and without employing toxic and racemizing reagents. This method resulted also useful for the immobilization, through the hydroxyl group, of FmocTyrOAll, FmocSerOAll, and FmocThrOAll, important building blocks for the synthesis of cyclic peptides.     

Electrophoretic and chromatographic evaluation of transgenic barley expressing a bacterial dihydrodipicolinate synthase

Nutritional quality of human and animal foodstuffs is determined by the content of essential amino acids. Barley is the fourth most important cereal of the world and the second most important cereal grown in the Czech Republic. Cereal grains such as barley contain insufficient levels of some essential amino acids, especially lysine. Dihydrodipicolinate synthase is the key enzyme involved in the regulatory step for lysine biosynthesis. Two constructs pBract214::sTPdapA and pBract214::mdapA containing the dapA gene from Escherichia coli coding for the bacterial dihydrodipicolinate synthase were used for transformation of barley. An Agrobacterium-mediated technique was used for transformation of immature embryos of spring barley cv. Golden Promise. Transgenic barley plants of the T0 and T1 generations were evaluated by PCR, real-time PCR, gel electrophoresis, and Western blot. Amino acid content was analyzed by HPLC after HCl hydrolysis. The lysine content in leaves of the T1 generation plant no. 5/5 was 50% higher than in wild-type plants; the lysine content in seeds of T2 generation plant no. 5/16 was 30% higher than in wild-type seeds of spring barley cv. Golden Promise.     

Rethinking Arsenate Coordination at the Surface of Goethite

When the truth stands on one leg : Arsenate coordinates at the water–goethite interface in a predominately monodentate fashion (see picture), a finding that impacts oxoanion bioavailability and challenges theories of mineral dissolution and surface complexation.

     

Dodecaborate cluster lipids with variable headgroups for boron neutron capture therapy: Synthesis, physical-chemical properties and toxicity

We have prepared two new boron-containing lipids with potential use in boron neutron capture therapy of tumors. These lipids consist of a diethanolamine frame with two myristoyl chains bonded as esters, and a butylene or ethyleneoxyethylene unit linking the doubly negatively charged dodecaborate cluster to the amino function of the frame, obtained by nucleophilic attack of the amino on the tetrahydrofurane and dioxane derivatives, respectively, of closo-dodecaborate. The latter cluster lipid can form liposomes at 25 °C whereas the former lipid at this temperature assembles into bilayer disks. Both lipids form stable liposomes when mixed with suitable helper lipids. The thermotropic behavior was found to be different for the two lipids, with the butylene lipid showing sharp melting transitions at surprisingly high temperatures. Toxicity in vitro and in vivo varies greatly, with the butylene derivative being more toxic than the ethyleneoxyethylene derivative.     

Crystal Structure of 2-{1-[(1-(2-Pyridinio)ethylidene)hydrazono]ethyl}pyridinium diperchlorate,the Product of Template Condensation in the Presence of Cr(III)

Abstract  In an attempt to synthesize a Cr(III) complex of 2′-[1-(2-pyridinyl)ethylidene]oxamohydrazide an azine product 2-{1-[(1-(2-pyridinio)ethylidene)hydrazono]ethyl}pyridinium diperchlorate was obtained by an electrophilic acyl substitution catalyzed by Cr(III). Its structure was determined by X-ray crystal analysis and showed significant changes in comparison to the corresponding unprotonated compound. The 2-{1-[(1-(2-pyridinio)ethylidene)hydrazono]ethyl}pyridinium diperchlorate crystallizes in the space group P2₁/n of the monoclinic crystal system with unit cell parameters a = 14.3809(3) ?, b = 24.1516(5) ?, c = 15.4471(3) ?, β = 99.930(2)°, V = 5284.74(19) ?³ and Z = 12, i.e. three molecules per asymmetric unit. Graphical Abstract  In the template condensation of the 2′-[1-(2-pyridinyl)ethylidene]oxamohydrazide in presence of the chromium(III) ion the 2-{1-[(1-(2-pyridinio)ethylidene)hydrazono]ethyl}pyridinium diperchlorate was obtained and characterized by NMR spectroscopy and X-ray crystallography. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Some New Results Related to Compact Matrix Operators in the Class((l_p)T,l_∞)

The main goal of this paper is to establish necessary and sufficient conditions for a matrix A ∈((lp)T,l∞), where T is an arbitrary triangle, 1 ≤ p ≤∞, to be a compact operator. In the past,only sufficient conditions were established in almost all of those cases, by using the Hausdorff measure of noncompactness. We improve those results by applying another method for the characterizations of compact linear operators between BK spaces.     

Exogenous crimes and the assessment of public safety efficiency and effectiveness

Annals of Operations Research - This work discusses the issue on how to include data about property and violent crimes in the production technology for the assessment of police technical...