Synthesis and chemical reactivity of the novel 3-chloro-3-(4-chlorocoumarin-3-yl)prop-2-enal

Vilsmeier-Haack formylation of 3-acetyl-4-hydroxycoumarin (1) afforded the unexpected 3-chloro-3-(4-chlorocoumarin-3-yl)prop-2-enal (3). Compound 3 reacted with p-toluidine and benzylamine producing Schiff base 4 and enamine 6, respectively. Treatment of compound 3 with hydrazine hydrate produced bis-coumarin 15 which upon treating with hydrazine hydrate afforded bis chromeno[4,3-c]pyrazole derivative 16. Compound 3 reacted with cyanoacetohydrazide under different conditions. Condensation of compound 3 with some heterocyclic amines and 1,2-N,N-binucleophiles was studied. Structures of the new synthesized products were deduced on the basis of their analytical and spectral data.     

Anti-Influenza a virus of a new oligosaccharide citric acid derivative isolated from Vigna angularis (ohwi et ohashi. var. Dainagon) Seeds

A new oligosaccharide citric acid derivative was isolated by hot aqueous extraction at 85?°C from Vigna angularis seeds, and it was purified using anion exchange chromatography DE-52. The structure was inferred by using UV, 1?D and 2?D NMR spectroscopy and HR-MALDI/MS, and identified as α-D-galactopyranosyl-(1→6)-α-D-galactopyranosyl-(1→6)-α-D-glucopyranosyle-(1→2)-β-D-fructofuranosyle citric acid. The isolated oligosaccharide citric acid derivative revealed promising anti-influenza A virus with 50% inhibition concentration (IC₅₀) of 0.162?nM/mL and 50% cytotoxic dose (CC₅₀) of >2.38?nM/mL.     

ELECTRO-MAGNETO-THERMOELASTIC PLANE WAVES IN MICROPOLAR SOLID INVOLVING TWO TEMPERATURES

<正>The model of equations of micropolar generalized magneto-thermoelasticity is introduced within the context of the theory of two temperatures generalized thermoelasticity and we consider a problem of an isotropic homogeneous micropolar medium taking into account the heat effects and allowing the magnetic field effects.A plane wave analysis is employed to obtain the exact formulas of the two temperatures(conductive and mechanical),displacement components, micro-rotation components,stresses,couple stresses,induced electric current,electric field and magnetic field.Arbitrary application is chosen to enable us to get the complete solution.The considered variables are presented graphically and discussions are made for the results.     

Studies on the Chemical Transformations of 6‐Methylchromone‐3‐carbonitrile under Nucleophilic Conditions

The chemical reactivity of 6‐methylchromone‐3‐carbonitrile ( 1 ) was studied towards some nucleophilic reagents. Reaction of carbonitrile 1 with malononitrile dimer and N′‐[(4‐methoxyphenyl)methylidene]‐2‐cyanoacetohydrazide ( 5 ) gave the unexpected chromeno[4,3‐b]pyridine 2 and benzoxocine‐3‐carbohydrazide 6 , respectively. Reaction of carbonitrile 1 with 3‐amino‐1,2,4‐triazole, 2‐aminobenzimidazole, 7‐chloro‐4‐hydrazinoquinoline and 3‐hydrazino‐5,6‐diphenyl‐1,2,4‐triazine proceeds via γ‐pyrone ring opening followed by cycloaddition onto the nitrile function leading to a variety of heterocyclic systems. Structures of the new synthesized products were deduced on the basis of their analytical and spectral data.     

Three-dimensional thermal shock problem of generalized thermoelastic half-space

A three-dimensional model of the generalized thermoelasticity with one relaxation time is established. The resulting non-dimensional coupled equations together with the Laplace and double Fourier transforms techniques are applied to a specific problem of a half space subjected to thermal shock and traction free surface. The inverses of Fourier transforms and Laplace transforms are obtained numerically by using the complex inversion formula of the transform together with Fourier expansion techniques. Numerical results for the temperature, thermal stress, strain and displacement distributions are represented graphically.     

Influence of a Kerr-Like Medium and the Detuning Parameter on the Statistical Aspects of the Intensity-Dependent-Coupling Hamiltonian

We study the interaction between a one-mode electromagnetic field and a two-level atom in the presence of a Kerr-like medium when the atom is prepared initially in the momentum eigenstate. The wave function is calculated by using the Schrodinger equation for a coherent electromagnetic field and an atom in the excited state. The effects of the Kerr-like medium and the detuning parameters on the statistical aspects of the intensity-dependent-coupling Hamiltonian such as, atomic momentum increment, momentum diffusion, the radiation force, and the field entropy are calculated. We investigate the effect of the detuning, Kerr-like medium and photon number operator on the field entropy.     

Synthesis and characterization of antibacterial semi-interpenetrating carboxymethyl chitosan/poly (acrylonitrile) hydrogels

Blend hydrogels composed of carboxymethyl chitosan (CMCh) and poly (acrylonitrile) (PAN) were synthesized via crosslinking method. Several analyses were made to investigate both physical and thermal properties of CMCh/PAN hydrogels like; FTIR, scanning electron microscope, XRD and thermogravimetric analysis (TGA). TGA results showed that CMCh/PAN hydrogels are thermally more stable than CMCh and their thermal stability increases as PAN content increases in the hydrogel. Moreover, the swelling behavior of CMCh/PAN hydrogels was studied in different buffer solutions. It was found that CMCh/PAN hydrogels swell much more than PAN especially at pH 9. The hydrogels sorption for different dyestuff and various metal ions like; Cu²⁺, Cd²⁺ and Co²⁺ were also studied. In this work, antibacterial characteristic of hydrogels was mainly investigated towards Escherichia coli (E. coli) as a serious disease-leading bacterium. All tested hydrogels have clearly presented good antibacterial activity as CMCh content increases in the hydrogels.     

A comparison between rate-equation and Fabry-Perot amplifier models of injection locked laser diodes

The rate-equation and the Fabry-Perot amplifier models for injection locked laser diodes are compared. Both models give identical results at the limiting case of no injected signal. The Fabry-Perot model predicts a wider locking bandwidth and is more useful for large signal applications. The rate-equation model is suitable for investigating the dynamic properties. Numerical results from both models are presented.     

The electronic structure of modulation-doped In0.53Ga0.47As/n-In0.52Al0.48As heterostructure

Summary The subband structure of modulation-doped InGaAs/InAlAs heterostructures is calculated in a variational self-consistent manner. The dependence on various device parameters is examined. The many-body exchange correlation effects are taken into account.     

Spectral and magnetic studies of polynuclear copper(II) complexes of Schiff base derived from ethylenediamine and ethylacetoacetate

Summary The Schiff base (L), prepared by the condensation of two molecules of ethyl acetoacetate and one molecule of ethylenediamine reacts with copper(II) chloride to give poiynuclear complexes of the type Cu₃L Cl₆, Cu₄L Cl₈, Cu₅L Cl₁₀, Cu₆L Cl₁₂, Cu₇L Cl₁₄ and Cu₈L Cl₁₆. Elemental analyses, molar conductivities, magnetic susceptibilities, x-ray powder diffraction and i.r. spectral studies have been used to characterize the complexes. The i.r. spectra show that the Schiff base binds in a tetradentate manner and the spectral and magnetic studies suggest the presence of a chlorine bridge between the copper atoms. The magnetic susceptibility of the complexes follows the Curie-Weiss law.