Excess Acoustical and Volumetric Properties and Theoretical Estimation of Ultrasonic Velocities in Binary Liquid Mixtures of 2-Chloroaniline with Acrylic Esters at 308.15 K

The ultrasonic velocities (u) and densities (??) for three binary mixture systems of 2-chloroaniline (CA) with ethyl acrylate (EA), butyl acrylate (BA), and 2-ethylhexyl acrylate (EHA) were measured over the entire mole fraction range at the temperature 308.15?K, including those of pure liquids. From these data, the deviations in ultrasonic velocity (??u), the excess molar volumes ( $V_{\mathrm{m}}^{\mathrm{E}}$ ), deviations in excess molar volume ( $\delta V_{\mathrm{m}}^{\mathrm{E}}$ ), deviations in isentropic compressibility (??k _S), excess intermolecular free lengths ( $L_{\mathrm{f}}^{\mathrm{E}}$ ), and excess acoustic impedances (Z ^E) have been calculated. The variations of these properties with solution composition are discussed in terms of molecular interactions among unlike molecules of the mixtures. The excess and deviation functions have been fitted to Redlich-Kister type polynomials and the corresponding standard deviations ??(Y ^E) have been calculated. The deviations and excess values were plotted against the mole fraction of CA over the whole composition range. The $V_{\mathrm{m}}^{\mathrm{E}}$ and ??k _S values are negative in the EA + CA and BA + CA systems but are positive in the EHA + CA system, which indicates the presence of specific interactions between unlike molecules. Further, theoretical values of the sound velocity in these mixtures have been evaluated using various theories and have been compared with experimental sound velocities to verify the applicability of such theories to the investigated systems. Two types of polynomial equations, f(x) and g(x), have been fitted to experimental values of ultrasonic velocities. The sound velocities obtained by these polynomials have extremely small deviations from the experimental values.     

High-throughput screening assay for the quantification of Cer d18:1/16:0, d18:1/24:0, d18:1/24:1, d18:1/18:0, d18:1/14:0, d18:1/20:0, and d18:1/22:0 in HepG2 cells using RapidFire mass spectrometry

Ceramides are known to be involved in various biological processes with their physiological levels elevated in various disease conditions such as diabetes, Alzheimer's, atherosclerosis. To facilitate the rapid screening of Cer d18:1/16:0, d18:1/24:0, d18:1/24:1, d18:1/18:0, d18:1/14:0, d18:1/20:0, and d18:1/22:0 inhibition in HepG2 cells, a RapidFire coupled to tandem mass spectrometry (RF–MS/MS) method has been developed. The RF platform provides an automated solid-phase extraction system that gave a throughput of 12.6 s per sample to an MS/MS system using electrospray ionization under the positive ion mode. Chromatographic separation of Cer d18:1/16:0, d18:1/24:0, d18:1/24:1, d18:1/18:0, d18:1/14:0, d18:1/20:0, and d18:1/22:0 was achieved using a ternary gradient on C₈ type E cartridge. The MS/MS ion transitions monitored were 538.2 → 264.2, 650.7 → 264.2, 648.6 → 264.2, 566.4 → 264.2, 510.4 → 264.2, 594.4 → 264.2, 622.5 → 264.2, and 552.3 → 250.2 for Cer d18:1/16:0, d18:1/24:0, d18:1/24:1, d18:1/18:0, d18:1/14:0, d18:1/20:0, d18:1/22:0, and the internal standard (Cer d17:1/18:0), respectively. The RF–MS/MS methodology showed an excellent performance with an average Z′ value of 0.5–0.7. This is the first report of an RF–MS/MS assay for screening of ceramides which is amenable for high-throughput screening.     

Facile synthesis of novel bis-derivatives of 2,5-diamino-thiadiazole/<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-thiocarbohydrazide and their biological perspective

A series of new bis derivatives of 2,5-thiadiazole and N,N′-thiocarbohydrazide along with their transition metal complexes were synthesized by green methods (sonochemical and microwave), i.e., energy and time efficient and operationally more simple than existing conventional methods. All the synthesized compounds were fully characterized by routine analytical techniques and subjected to a preliminary biological screening. These novel characterized compounds were screened for antimicrobial activities and showed promising results. A few potent compounds were also tested for antitumor activities against MDA-MB231 (human breast carcinoma cell line) and compound 5 has emerged as a potential antitumor compound followed by compound 2, 10 and 9, with IC₅₀ values of 29.48, 32.25, 32.34 and 34.34 μg/ml, respectively. To understand the binding interactions of these compounds, in silico studies were performed using the AUTODOCK 4.2 suite and found to be supportive of the experimental results.     

Transition Metal Ion-binding Properties of a 14-Membered N2O2S2- Macrobicyclic Ligand

The selective liquid–liquid extraction of various transition metal cations from the aqueous phase to the organic phase was carried out using a 14-membered N₂O₂S₂-macrobicycle. Metal picrates such as Pb²⁺, Co²⁺, Zn²⁺, Ni²⁺,Cu²⁺ and Cd²⁺ were used in this extraction studies. It was found that the ligand showed moderate selectivity towards Pb²⁺ only among the other metals. The extraction constant (log K _ex) was determined to be 13.8 for Pb²⁺ complex.     

Alkali promoted rare earth metal phosphates for vapour phase O-alkylation of α- and β-naphthols with methanol

The vapor-phase catalytic O-alkylation of - and -naphthols with methanol has been investigated over lanthanum, cerium, samarium, and antimony phosphate catalysts promoted with cesium hydroxide. Among various catalysts investigated, the Cs-SmPO₄ combination catalyst provided better catalytic activity and selectivity. The CsOH promoter suppressed formation of C-alkylated side products and enhanced the O-alkylation selectivity. Characterization of these catalysts by X-ray diffraction and FT-infrared techniques revealed that the cesium promoter has no influence on the bulk structure of the catalysts. Temperature programmed desorption of anhydrous ammonia over promoted and unpromoted catalysts revealed that the cesium promoter decreases total surface acidity of the catalysts.     

Highly efficient Pd‐PEPPSI‐IPr catalyst for N‐(4‐pyridazinyl)‐bridged bicyclic sulfonamides via Suzuki–Miyaura coupling reaction

A protocol for the Suzuki–Miyaura coupling of novel 2‐(6‐chloropyridazin‐3‐yl)‐5‐(aryl/heteroarylsulfonyl)‐2,5‐diazabicyclo[2.2.1]heptanes and heteroarylboronic acids to afford variety of coupled products was realized. Pd‐PEPPSI‐IPr catalyst was found to be a powerful and reusable catalyst under relatively mild reaction conditions.     

Bis(μ‐phenyl 2‐pyridyl ketone N4,N4‐butane‐1,4‐diylthiosemicarbazonato)bis[chlorocopper(II)]

The title compound, [Cu₂(C₁₇H₁₇N₄S)₂Cl₂], exhibits a dimeric structure related by a centre of symmetry. The monomers are linked to each other by the longest Cu—S apical distance observed to date among Cu^II square‐pyramidal complexes of N⁴‐substituted thio­semicarbazones. Each Cu^II atom deviates from the coordination square plane, which contains the pyrid­yl and imine N atoms, the thiol­ate S atom and the Cl⁻ anion, towards the S atom of the adjacent monomer. The dimers pack in a zigzag manner through the crystal.     

Effect of metals on UV-excited plasmonic lithography for sub-50 nm periodic feature fabrication

This paper describes and compares the effect of metal films, such as aluminum (Al) and silver (Ag) on UV-excited two-beam surface plasmon interference nanolithography. A planar four-layer configuration has been employed to study the light intensity distribution on the recording medium. It is observed that high-density sub-50 nm periodic structures were achievable by employing the above-mentioned metal films when interrogated with p-polarized, 364 nm illumination wavelength source. It is found that the obtained periodic feature shows good exposure depth and high contrast when Al is used as a metal film. The initial experimental result of planar four-layer configuration is also presented.