Discovery and evaluation of inhibitory activity and mechanism of arylcoumarin derivatives on Theileria annulata enolase by in vitro and molecular docking studies

Molecular Diversity - In this study, the inhibition potential of 3- and 4-arylcoumarin derivatives on Theileria annulata enolase (TaENO) was assessed for the first time in the literature. Firstly,...     

Fatty Acid Composition and Antioxidant Activity of Ranunculus constantinopolitanus

Chemistry of Natural Compounds -     

Effect of the crystal structure on the X-ray intensity ratios of 3d metals

The linear muffin-tin-orbital method is used to calculate the d electron populations of 3d metals in different crystal structures. It is found that valence electronic structure and hence the Kβ/Kα X-ray intensity ratio (R) of a 3d metal changes with the crystal structure. It is concluded that R of a 3d metal depends on the energy band structure rather than the chemical environment.     

Dual-frequency division de-multiplexer based on cascaded photonic crystal waveguides

A dual-frequency division de-multiplexing mechanism is demonstrated using cascaded photonic crystal waveguides with unequal waveguide widths. The de-multiplexing mechanism is based on the frequency shift of the waveguide bands for the unequal widths of the photonic crystal waveguides. The modulation in the waveguide bands is used for providing frequency selectivity to the system. The slow light regime of the waveguide bands is utilized for extracting the desired frequency bands from a wider photonic crystal waveguide that has a relatively larger group velocity than the main waveguide for the de-multiplexed frequencies. In other words, the wider spatial distribution of the electric fields in the transverse direction of the waveguide for slow light modes is utilized in order to achieve the dropping of the modes to the output channels. The spectral and spatial de-multiplexing features are numerically verified. It can be stated that the presented mechanism can be used to de-multiplex more than two frequency intervals by cascading new photonic crystal waveguides with properly selected widths.     

A Stochastic Competitive Research and Development Race Where “Winner Takes All” with Lower and Upper Bounds

The paper analyzes an environment in which several firms compete over the development of a project. Each firm decides how much to invest in the project while adhering to firm-specific lower and upper investment bounds. The completion time of the project by a firm has exponential distribution with rate that depends linearly on the investment of the firm. The firm that completes the project first collects all its revenues whereas the remaining firms earn nothing. The paper establishes the existence and uniqueness of both the Nash equilibrium and the globally optimal solution, provides explicit representations parametrically in the interest rate, and constructs computationally efficient methods to solve these two problems. It also examines sensitivity of Nash equilibrium to marginal changes in lower and upper bounds.     

Electrochemical signal modulation in homogeneous solutions using the formation of an inclusion complex between ferrocene and β-cyclodextrin on a DNA scaffold

Two DNA conjugates modified with ferrocene and β-cyclodextrin were prepared as a pair of probes that work cooperatively for DNA sensing, in which the electrochemical signal of ferrocene on one probe was significantly "quenched" by the formation of an inclusion complex with β-cyclodextrin of the other probe on the DNA templates.     

Synthesis,antioxidant and antitumor activities of some of new cyclobutane containing triazoles derivatives

Abstract

Thiosemicarbazides (2a–e) were obtained by the interaction of furan-2-carboxylic acid hydrazide (1) with five different isothiocyanate (RNCS) derivatives. By addition of KOH to the reaction medium, ethyl, allyl, phenyl and benzyl, p-tolyl substituted 1,2,4-triazoles (3a–e) were obtained. 3a–e were dissolved in dry acetone containing K₂CO₃ in the presence of 2-chloro-1-(3-methyl-3-mesitylcyclobutyl) ethanone (4) to give 3,4,5-trisubstituted 1,2,4-triazole sulfanyl compounds containing a cyclobutane ring (5a–e). The structures of the final compounds were confirmed by elemental analyses, FT-IR, ¹H-NMR and ¹³C-NMR. The antioxidant and antitumor properties of the synthesized compounds were also investigated. Three of the triazole derivatives with p-tolyl, benzyl and phenyl substituents (5c–e) displayed good antioxidant and antitumor activity in comparison to the standards.     

Synthesis and In-Vitro Antimicrobial Activity of Novel Aminophosphinic Acids Containing Cyclobutane and 1,3-Thiazole

Abstract

The compounds {[4-(3-methyl-3-aryl(mesityl-phenyl-tetralino)cyclobutyl)-1,3-thiazol-2-yl]amino}(aryl)methyl-phosphinic acids 2a–l were prepared by condensation of 2-amino-4-(3-aryl(mesityl-phenyl-tetralino)-3-methylcyclobutyl) thiazoles 1a–c with various aromatic aldehydes and hypophosphorous acid through a one-pot reaction. The characterizations of these compounds were obtained by elemental analyses, infrared (IR) spectra, and ¹H, ¹³C, and ³¹P NMR (nuclear magnetic resonance) techniques. The synthesized compounds were tested in vitro against one Gram-positive and two Gram-negative bacterial strains, one mycobacterial strain, and a fungus Candida albicans. Compound 2f showed significant activity against Staphylococcus aureus, whereas the others had no remarkable activity on this strain. Compound 2g was found to be more active than the others against Mycobacterium fortuitum at an MIC (minimum inhibitory concentration) value of 32 μg/mL. The antibacterial and antifungal activities of 2a–l were also compared with various standard drugs.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Biological Activities. Table S1. Figures S1–S6.]

GRAPHICAL ABSTRACT      

Room temperature ferromagnetism in Mn-doped ZnS nanocrystalline thin films grown by sol–gel dip coating process

Nanocrystalline Zn_1?xMn_xS (x = 0.00, 0.01, 0.02, 0.03, 0.05, and 0.1) thin films having different Mn content were grown by the sol–gel dip coating process. The effect of Mn content on the structural, optical and magnetic properties of Zn_1?xMn_xS nanocrystalline thin films were investigated. X-ray diffraction results showed the presence of single hexagonal phase corresponding to ZnS with a preferred orientation along the ZnS (002) hexagonal plane direction without any detectable secondary phase, suggesting the incorporation of Mn ions into the ZnS lattice. Scanning electron microscope revealed the surface of the nanocrystalline films to be homogeneous and dense and the grains of the film surface were randomly scattered. In ultraviolet–visible measurements, the band gap energy corresponding to the absorption edge estimated were found to be 3.59–3.23 eV depending on the Mn doping ratio. Magnetic measurements showed that a paramagnetic behavior at 5 K and ferromagnetic behavior at 300 K.