Synthesis and spectral characterization of macrocyclic Schiff base by reaction of 2,6-diaminopyridine and 1,4- bis (2-carboxyaldehydephenoxy)butane and its CuII, NiII, PbII, CoIII and LaIII complexes

A new macrocyclic ligand, 1,3,5-triaza-2,4:7,8:15,16-tribenzo-9,15-dioxacycloheptadeca-1,5-diene (L) was synthesized by reaction of 2,6-diaminopyridine with 1,4-bis(2-carboxyaldehydephenoxy)butane. Then, its Cu^II, Ni^II, Pb^II, Co^III and La^III complexes were synthesized by the template effect by reaction of 2,6-diaminopyridine and 1,4-bis (2-carboxyaldehydephenoxy)butane and Cu(NO₃)₂ · 3H₂O, Ni(NO₃)₂ · 6H₂O, Pb(NO₃)₂, Co(NO₃)₂ · 6H₂O, La (NO₃)₃ · 6H₂O, respectively. The ligand and its metal complexes were characterized by elemental analysis, IR, ¹H- and ¹³C-n.m.r., UV-vis spectra, magnetic susceptibility, thermal gravimetric analysis, conductivity measurements and mass spectra. All complexes are diamagnetic and the Cu^II complex is binuclear. The Co^II complex was oxidised to Co^III.     

Phytochemicals,antioxidant, anti-acetyl-cholinesterase,and antimicrobial activities of decoction and infusion of Pelargonium graveolens

Abstract

In Tunisia, Pelargonium graveolens is widely consumed as a food aromatizing hydrosol. Recent studies have shown the potential of plant solvent-free extracts as food and pharmaceutical natural additives. Accordingly, in this study, we investigate the phenolic content, the volatile fractions of green P. graveolens extracts such as infusion and decoction, and we evaluate their biological activities. The total phenolic content of the infusion (27.05?mg GAE/gDM) is significantly different from that of decoction (31.2?mg GAE/gDM). The GC-MS analysis identified about twenty volatile components in both extracts. The DPPH inhibition and the β-carotene bleaching tests of the infusion and the decoction had considerable results. Besides, infusion and decoction exhibited a relatively high anti-acetyl-cholinesterase activity and a considerable antimicrobial activity against S. aureus, among three tested pathogenic bacteria.     

Spectroscopic and Electrochemical Studies of Transition Metal Complexes with N,N′-Bis(2-aminothiophenol)-1,7-bis(2-formylphenyl)-1,4,7-trioxaheptane and Structure Effects on Extractability of Ligand towards some Divalent Cations

Summary. La(III), Cu(II), Ni(II), and Zn(II) metal complexes with a novel quadridentate Schiff base derived from 1,7-bis(2-formylphenyl)-1,4,7-trioxaheptane and 2-aminothiophenol were synthesized and characterized by microanalytical data, elemental analysis, magnetic measurements, ¹H NMR, ¹³C NMR, UV-Vis, IR, mass spectra, cyclic voltammetric and conductance measurements. The extractability of divalent cations was evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. The highest extraction percentage of Cu²⁺ and Ni²⁺ showed pH 7.0 and 6.4. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) and nickel(II) from the aqueous phase to the organic phase.     

Prototropie et synthèses nouvelles dans la série des dihydro-5,6 hydroxy-4 pyrones-2 et pyridones-2

The multistep catalytic reduction of 6-methyl-4-hydroxy-2-pyrone allows isolation of two intermediate compounds: the biologically active parasorbic acid ( 5 ) and the 6-methyl-5,6-dihydro-4-hydroxy-2-pyrone ( 2 ). The desmotropic keto-enol equilibrium lies on the enol side, with the 4rhydroxy structure. Primary arylamines readily react with 2 , leading to corresponding 2-pyridones 8 ; with methylamine, the aliphatic intermediate 7 resulting from ring attack at the 2 position can be isolated. Also further functionnalization of both dihydropyrone and 2-pyridone is possible by selective bromination at position 3.     

Synthesis and Characterization of New Macrocyclic Cu（Ⅱ） Complexes from Various Diamines, Copper（Ⅱ） Nitrate and 1,4-Bis（2-formylphenoxy）butane

Six new macrocyclic complexes were synthesized by a template reaction of 1,4-bis（2-formylphenoxy）butane with diamines and Cu（NO3）2·3H2O and their structures were proposed on the basis of elemental analysis, FT-IR, UV-Vis, magnetic susceptibility measurements, molar conductivity measurements and mass spectra. The metal to ligand molar ratios of the Cu（Ⅱ） complexes were found to be 1 ： 1. The Cu（Ⅱ） complexes are 1 ： 2 electrolytes as shown by their molar conductivities （∧m） in DMF at 10^-3 mol·L^-1. Due to the existence of free ions the Cu（Ⅱ） complexes are electrically conductive. Their configurations were proposed to be probably distorted octahedral.     

Synthesis of bipyrazoles and pyrazoloisoxazoles from 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one

Phenylhydrazine or hydrazine react with 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one ( 1 ) to give 4-acetoacetyl-3-methylpyrazolin-5-ones 4 . The synthesis of bipyrazoles and pyrazoloisoxazoles from 4 are reported.     

Films courbés minces ferromagnétiques

We consider a thin curved ferromagnetic film not submitted to an external magnetic field. The behavior of the film is described by an energy depending on the magnetization of the film verifying the saturation constraint. The energy is composed of an induced magnetostatic energy and an energy term with density including the exchange energy and the anisotropic energy. We study the behavior of this energy when the thickness of the curved film goes to zero. We show with Γ-convergence arguments that the minimizers of the free energy converge to the minimizers of a local energy depending on a two-dimensional magnetization. To cite this article: H. Zorgati, C. R. Acad. Sci. Paris, Ser. I 340 (2005).     

Hydrazidoyl halides in synthesis of Δ2-1,3,4-selenadiazolin-5-ones

Reaction of hydrazidoyl halides 1-5 with potassium selenocyanate in ethanol produces the corresponding 2,4-disubstituted-5-iminoδ²-1,3,4-selenadiazolines, 9-13 respectively. Nitrosation of the latter yields the N-nitroso derivatives 14-17 , which decompose upon refluxing in xylene to give 2,4-disubstituted Δ²-1,3,4-selenadiazolin-5-ones in good yield. Compounds 9-13 give the respective N-acetyl derivatives 22-26 and N-benzoyl derivatives 27-31 with acetic anhydride and benzoyl chloride in pyridine.     

Novel cyclohexyl‐based aminophosphine ligands and use of their Ru(II) complexes in transfer hydrogenation of ketones

Two new aminophosphines – furfuryl‐(N‐dicyclohexylphosphino)amine, [Cy₂PNHCH₂–C₄H₃O] ( 1 ) and thiophene‐(N‐dicyclohexylphosphino)amine, [Cy₂PNHCH₂–C₄H₃S] ( 2 ) – were prepared by the reaction of chlorodicyclohexylphosphine with furfurylamine and thiophene‐2‐methylamine. Reaction of the aminophosphines with [Ru(η⁶‐p‐cymene)(μ‐Cl)Cl]₂ or [Ru(η⁶‐benzene)(μ‐Cl)Cl]₂ gave corresponding complexes [Ru(Cy₂PNHCH₂–C₄H₃O)(η⁶‐p‐cymene)Cl₂] ( 1a ), [Ru(Cy₂PNHCH₂–C₄H₃O)(η⁶‐benzene)Cl₂] ( 1b ), [Ru(Cy₂PNHCH₂–C₄H₃S)(η⁶‐p‐cymene)Cl₂] ( 2a ) and [Ru(Cy₂PNHCH₂–C₄H₃S)(η⁶‐benzene)Cl₂] ( 2b ), respectively, which are suitable catalyst precursors for the transfer hydrogenation of ketones. In particular, [Ru(Cy₂PNHCH₂–C₄H₃S)(η⁶‐benzene)Cl₂] acts as a good catalyst, giving the corresponding alcohols in 98–99% yield in 30 min at 82 °C (up to time of flight ≤ 588 h^?1). Copyright © 2014 John Wiley & Sons, Ltd.