Experimental demonstration of continuous variable quantum erasing

We experimentally demonstrate the concept of continuous variable quantum erasing. The amplitude quadrature of the signal state is labeled to another state via a quantum nondemolition interaction, leading to a large uncertainty in the determination of the phase quadrature due to the inextricable complementarity of the two observables. We show that by erasing the amplitude quadrature information we are able to recover the phase quadrature information of the signal state.     

Identification of in vitro metabolites of the novel anti-tumor thiosemicarbazone, DpC, using ultra-high performance liquid chromatography–quadrupole-time-of-flight mass spectrometry

Di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC) is a promising analogue of the dipyridyl thiosemicarbazone class currently under development as a potential anti-cancer drug. In fact, this class of agents shows markedly greater anti-tumor activity and selectivity than the clinically investigated thiosemicarbazone, Triapine®. However, further development of DpC requires detailed data concerning its metabolism. Therefore, we focused on the identification of principal phase I and II metabolites of DpC in vitro. DpC was incubated with human liver microsomes/S9 fractions and the samples were analyzed using ultra-performance liquid chromatography (UPLC^TM) with electrospray ionization quadrupole-time-of-flight (Q-TOF) mass spectrometry. An Acquity UPLC BEH C₁₈ column was implemented with 2 mM ammonium acetate and acetonitrile in gradient mode as the mobile phase. The chemical structures of metabolites were proposed based on the accurate mass measurement of the protonated molecules as well as their main product ions. Ten phase I and two phase II metabolites were detected and structurally described. The metabolism of DpC occurred via oxidation of the thiocarbonyl group, hydroxylation and N-demethylation, as well as the combination of these reactions. Conjugates of DpC and the metabolite, M10, with glucuronic acid were also observed as phase II metabolites. Neither sulfate nor glutathione conjugates were detected. This study provides the first information about the chemical structure of the principal metabolites of DpC, which supports the development of this promising anti-cancer drug and provides vital data for further pharmacokinetic and in vivo metabolism studies.

Exploration of the electrophoretic behaviour of borane cluster anions and of the capability of capillary electrophoresis to separate them chirally

Mobilities of investigated boron cluster compounds in 3-(N-morpholino)propanesulfonic and phosphate buffers adjusted to pH 7 either with sodium hydroxide or with tris(hydroxymethyl)aminomethane depend on both buffer ions. The zone width and zone asymmetry, which are usually markedly higher than those of organic or common inorganic ions of comparable size, depend on the type of the borane cluster anion. Unusual shapes of zones of two investigated compounds have been found in tris phosphate buffer. Acetonitrile was superior to methanol as an organic additive to separation systems from the viewpoint of the zone symmetry and separation speed. Narrow trigonal zones, typical of organic ions non-interacting with the capillary wall, have been observed for some bridged sandwich cobalt complexes in run buffers with the addition of acetonitrile. The interaction of borane cluster anions with beta-cyclodextrin cavity is excessively strong in purely aqueous solutions. Methanol and acetonitrile, which generally weaken the interaction, sometimes affect the separation enantioselectivity of various compounds in different ways in addition to the weakening effect. Chiral discrimination was reached for all ten investigated anions, which belong to four different structural types of cluster boranes. Stability constants estimated for some analyte-beta-cyclodextrin complexes range between 100 and 1800 l/mol in acceptable separations. The relative difference of the constants was from 3 to 20%.     

Water-Soluble Polymeric Carbon Nitride Colloidal Nanoparticles for Highly Selective Quasi-Homogeneous Photocatalysis

Heptazine-based polymeric carbon nitrides (PCN) are promising photocatalysts for light-driven redox transformations. However, their activity is hampered by low surface area resulting in low concentration of accessible active sites. Herein, we report a bottom-up preparation of PCN nanoparticles with a narrow size distribution (ca. 10±3 nm), which are fully soluble in water showing no gelation or precipitation over several months. They allow photocatalysis to be carried out under quasi-homogeneous conditions. The superior performance of water-soluble PCN, compared to conventional solid PCN, is shown in photocatalytic H₂O₂ production via reduction of oxygen accompanied by highly selective photooxidation of 4-methoxybenzyl alcohol and benzyl alcohol or lignocellulose-derived feedstock (ethanol, glycerol, glucose). The dissolved photocatalyst can be easily recovered and re-dissolved by simple modulation of the ionic strength of the medium, without any loss of activity and selectivity.     

Determination of brominated phenols in water samples by on-line coupled isotachophoresis with capillary zone electrophoresis

A method for determination of nine brominated phenols as environmental risk compounds was developed by on-line coupled capillary isotachophoresis and capillary zone electrophoresis (ITP–CZE). For ITP step, 1 × 10⁻² mol L⁻¹ hydrochloric acid with 3 × 10⁻² mol L⁻¹ ammediol pH 9.1 was used as the leading electrolyte, and 3 × 10⁻² mol L⁻¹ β-alanine with 2 × 10⁻² mol L⁻¹ sodium hydroxide pH 10.05 was used as the terminating electrolyte. As the background electrolyte for CZE separation, 2.5 × 10⁻² mol L⁻¹ β-alanine with 2.5 × 10⁻² mol L⁻¹ lysine pH 9.6 was used. All electrolytes contained 0.05% or 0.1% (m/v) hydroxyethylcellulose to suppress the electroosmotic flow. UV detection at wavelength 220 nm was used. Detection limits in order of tens of nmol L⁻¹ were achieved. Good repeatability of migration times (less than 0.33% RSD) and good repeatability of peak areas (less than 7.19% RSD) at concentration level 5 × 10⁻⁸ mol L⁻¹ were observed. Developed ITP–CZE method was applied to determination of brominated phenols in spiked tap and river water samples.     

A H, C and N NMR spectroscopic and GIAO DFT study of ethyl 5-oxo-2-phenyl-4-(2-phenylhydrazono)-4,5-dihydro-1H-pyrrole-3-carboxylate

¹⁵N-Labelled ethyl 5-oxo-2-phenyl-4-(2-phenylhydrazono)-4,5-dihydro-1H-pyrrole-3-carboxylate was synthesized by azo-coupling of diazotized aniline (using Na¹⁵NO₂ , 99% ¹⁵N) with ethyl 4,5-dihydro-5-oxo-2-phenyl-(1H)-pyrrole-3-carboxylate. The product was formed as a tautomeric hydrazone mixture as confirmed by ¹³C and ¹⁵N chemical shifts, and was obtained as a mixture of E and Z isomers according to ⁿJ(¹⁵N, ¹³C). A comparison of the ¹H NMR data with GIAO DFT calculations enabled determination of the configuration of the carboxy ester group in both isomers.     

Alkaloids from some amaryllidaceae species and their cholinesterase activity

Alkaloid extracts of four Amaryllidaceae species were studied with respect to their acetylcholinesterase and butyrylcholinesterase inhibitory activity and alkaloid patterns. Twenty-one alkaloids were determined by GC/MS, and seventeen of them identified from their mass spectra and retention times. The GC/MS analysis of the alkaloid extract of Nerine filamentosa is the first phytochemical investigation of this species. Promising erythrocytic acetylcholinesterase inhibitory activity was demonstrated by the alkaloid extracts of Narcissus poeticus var recurvus, Nerine filifolia and N. filamentosa (IC(50,HuAChE) = 6.0 +/- 0.1 microg/mL; IC(50,HuAChE) = 18.5 +/- 0.8 microg/mL, IC(50,HuAChE) = 21.6 +/- 1.1 microg/mL). The most potent inhibitory activity against serum butyrylcholinesterase was shown by extracts of Sternbergia lutea and Nerinefilamentosa (IC(50,HuBuChE) = 3.7 +/- 0.1 microg/mL; IC(50.HuBuChE) = 13.0 +/- 0.7 microg/mL).     

O- and N-alkylated diketopyrrolopyrrole derivatives

The alkylation of 3-phenyl-6-(2-thienyl)pyrrolo[3,4-c]pyrrole-1,4-dione with 1-bromo-2-ethylhexane was performed. Besides the expected N,N′-dialkylated product, both possible N,O-dialkyl derivatives were isolated and identified for the first time. The position of the alkyl substituents in all three dialkylated isomers was determined by 2D ¹H and ¹³C NMR spectroscopy.     

Remote stereoselective deconjugation of α,β-unsaturated esters by simple amidation reactions

The thermodynamically disfavored isomerization of α,β-unsaturated esters to deconjugated β,γ-unsaturated analogues occurs readily when coupled to an amidation. Within the framework of macrocyclic derivatives, it is shown that 15, 16, and 18 membered macrocycles react with tBuOK and anilines to generate, in one-pot, β,γ-unsaturated amides (yields up to 88%). Importantly, single (chiral) diastereomers are isolated (d.r. > 49 : 1, ¹H NMR) irrespective of the size and nature of the rings, showing an effective transmission of remote stereochemistry during the isomerization process. CSP-chromatographic resolution and absolute configuration determination by VCD are achieved.     

Fuzzy Horn logic I

The paper presents generalizations of results on so-called Horn logic, well-known in universal algebra, to the setting of fuzzy logic. The theories we consider consist of formulas which are implications between identities (equations) with premises weighted by truth degrees. We adopt Pavelka style: theories are fuzzy sets of formulas and we consider degrees of provability of formulas from theories. Our basic structure of truth degrees is a complete residuated lattice. We derive a Pavelka-style completeness theorem (degree of provability equals degree of truth) from which we get some particular cases by imposing restrictions on the formulas under consideration. As a particular case, we obtain completeness of fuzzy equational logic.