Pyrazoles and Pyrazolines as Anti-Inflammatory Agents

The five-membered heterocyclic group of pyrazoles/pyrazolines plays important role in drug discovery. Pyrazoles and pyrazolines present a wide range of biological activities. The synthesis of the pyrazolines and pyrazole derivatives was accomplished via the condensation of the appropriate substituted aldehydes and acetophenones, suitable chalcones and hydrazine hydrate in absolute ethanol in the presence of drops of glacial acetic acid. The compounds are obtained in good yields 68–99% and their structure was confirmed using IR, ¹H-NMR, ¹³C-NMR and elemental analysis. The novel derivatives were studied in vitro for their antioxidant, anti-lipid peroxidation (AAPH) activities and inhibitory activity of lipoxygenase. Both classes strongly inhibit lipid peroxidation. Compound 2g was the most potent lipoxygenase inhibitor (IC₅₀ = 80 µM). The inhibition of the carrageenin-induced paw edema (CPE) and nociception was also determined, with compounds 2d and 2e being the most potent. Compound 2e inhibited nociception higher than 2d. Pyrazoline 2d was found to be active in a preliminary test, for the investigation of anti-adjuvant-induced disease (AID) activity. Pyrazoline derivatives were found to be more potent than pyrazoles. Docking studies of the most potent LOX inhibitor 2g highlight hydrophobic interactions with VAL126, PHE143, VAL520 and LYS526 and a halogen bond between the chlorine atom and ARG182.     

Rhodium Indenyl NHC and Fluorenyl-Tethered NHC Half-Sandwich Complexes: Synthesis,Structures and Applications in the Catalytic C−H Borylation of Arenes and Alkanes

Indenyl (Ind) rhodium N-heterocyclic carbene (NHC) complexes [Rh(η⁵-Ind)(NHC)(L)] were synthesised for 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazol-2-ylidene (SIPr) with L=C₂H₄ ( 1 ), CO ( 2 a ) and cyclooctene (COE; 3 ), for 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene (SIMes) with L=CO ( 2 b ) and COE ( 4 ), and 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) with L=CO ( 2 c ) and COE ( 5 ). Reaction of SIPr with [Rh(Cp*)(C₂H₄)₂] did not give the desired SIPr complex, thus demonstrating the “indenyl effect” in the synthesis of 1 . Oxidative addition of HSi(OEt)₃ to 3 proceeded under mild conditions to give the Rh silyl hydride complex [Rh(Ind){Si(OEt)₃}(H)(SIPr)] ( 6 ) with loss of COE. Tethered-fluorenyl NHC rhodium complexes [Rh{(η⁵-C₁₃H₈)C₂H₄N(C)C₂H_xNR}(L)] (x=4, R=Dipp, L=C₂H₄: 11 ; L=COE: 12 ; L=CO: 13 ; R=Mes, L=COE: 14 ; L=CO: 15 ; x=2, R=Me, L=COE: 16 ; L=CO: 17 ) were synthesised in low yields (5–31 %) in comparison to good yields for the monodentate complexes (49–79 %). Compounds 3 and 1 , which contain labile alkene ligands, were successful catalysts for the catalytic borylation of benzene with B₂pin₂ (Bpin=pinacolboronate, 97 and 93 % PhBpin respectively with 5 mol % catalyst, 24 h, 80 °C), with SIPr giving a more active catalyst than SIMes or IMes. Fluorenyl-tethered NHC complexes were much less active as borylation catalysts, and the carbonyl complexes were inactive. The borylation of toluene, biphenyl, anisole and diphenyl ether proceeded to give meta substitutions as the major product, with smaller amounts of para substitution and almost no ortho product. The borylation of octane and decane with B₂pin₂ at 120 and 140 °C, respectively, was monitored by ¹¹B NMR spectroscopy, which showed high conversions into octyl and decylBpin over 4–7 days, thus demonstrating catalysed sp³ C−H borylation with new piano stool rhodium indenyl complexes. Irradiation of the monodentate complexes with 400 or 420 nm light confirmed the ready dissociation of C₂H₄ and COE ligands, whereas CO complexes were inert. Evidence for C−H bond activation in the alkyl groups of the NHC ligands was obtained.     

Giant Magnetoresistance in the Half‐Metallic Double‐Perovskite Ferrimagnet Mn2FeReO6

The first transition‐metal‐only double perovskite compound, Mn²⁺₂Fe³⁺Re⁵⁺O₆, with 17 unpaired d electrons displays ferrimagnetic ordering up to 520 K and a giant positive magnetoresistance of up to 220 % at 5 K and 8 T. These properties result from the ferrimagnetically coupled Fe and Re sublattice and are affected by a two‐to‐one magnetic‐structure transition of the Mn sublattice when a magnetic field is applied. Theoretical calculations indicate that the half‐metallic state can be mainly attributed to the spin polarization of the Fe and Re sites.     

The role of the configurational force balance in the nonequilibrium epitaxy of films

We discuss the epitaxial growth of an elastic film, allowing for stress and diffusion within the film surface as well as nonequilibrium interactions between the film and the vapor. Our approach, which relies on recent ideas concerning configurational forces, is based on: (i) standard (Newtonian) balance laws for forces and moments together with an independent balance law for configurational forces; (ii) atomic balances, one for each species of mobile atoms; (iii) a mechanical version of the second law that accounts for temporal changes in free energy, energy flows due to atomic transport, and power expended by both standard and configurational forces; (iv) thermodynamically consistent constitutive relations for the film surface and for the interaction between the surface and the vapor environment. The normal component of the configurational force balance at the surface represents a generalization, to a dynamical context involving dissipation, of a condition that would arise in equilibrium by considering variations of the total free energy with respect to the configuration of the film surface. Our final results consist of partial differential equations that govern the evolution of the film surface.     

Interface Evolution in Three Dimensions¶with Curvature-Dependent Energy¶and Surface Diffusion:¶Interface-Controlled Evolution,Phase Transitions,Epitaxial Growth of Elastic Films

When the interfacial energy is a nonconvex function of orientation, the anisotropic-curvature-flow equation becomes backward parabolic. To overcome the instability thus generated, a regularization of the equation that governs the evolution of the interface is needed. In this paper we develop a regularized theory of curvature flow in three dimensions that incorporates surface diffusion and bulk-surface interactions. The theory is based on a superficial mass balance; configurational forces and couples consistent with superficial force and moment balances; a mechanical version of the second law that includes, via the configurational moments, work that accompanies changes in the curvature of the interface; a constitutive theory whose main ingredient is a positive-definite, isotropic, quadratic dependence of the interfacial energy on the curvature tensor. Two special cases are investigated: (i) the interface is a boundary between bulk phases or grains, and (ii) the interfaceseparates an elastic thin film bonded to a rigid substrate from a vapor phase whose sole action is the deposition of atoms on the surface.     

The detection of iron protoporphyrin (heme b) in phytoplankton and marine particulate material by electrospray ionisation mass spectrometry – comparison with diode array detection

A mass spectrometric (MS) method for the identification of iron protoporphyrin (IX) (FePTP, heme b) in marine particulate material and phytoplankton is described. Electrospray ionisation of FePTP produced the molecular Fe(III)PTP⁺ ion (m/z = 616) or the pseudomolecular [Fe(II)PTP + H]⁺ ion (m/z = 617), depending on the oxidation state of the central iron ion. Collision induced dissociation (CID) in the ion trap mass spectrometer resulted in a single detected product ion (m/z = 557) indicative of loss of ethanoic acid from a carboxylic acid side chain. Widening the isolation width to 616 ± 3 resulted in production of a mass spectrum demonstrating the distinctive isotopic ratio of the iron containing fragment, further increasing the specificity of the analysis. Selective reactant monitoring (SRM) of the fragment ion (m/z = 557) was applied to the detection of FePTP after chromatography of ammoniacal OGP extracts of marine samples. The detection limit for FePTP analysed by SRM after chromatography was 1.2 ± 0.5 fmol. For phytoplankton samples, reasonably good agreement was achieved between results obtained with SRM and those obtained by monitoring absorbance at λ = 400 nm using a diode array detector (DAD). Use of SRM for analysis of particulate material obtained from the high latitude North Atlantic allowed for the analysis of FePTP in the presence of a co-eluting compound that interfered with detection by DAD. Simultaneous collection of mass spectra from m/z = 300 to 1500 resulted in identification of the pseudomolecular ion for the interfering compound. The CID fragmentation pattern and UV–visible mass spectra indicated that the interfering compound was a previously unidentified chlorin type compound. Comparison of FePTP determined by SRM and DAD on samples where this compound could not be detected showed that results collected using the two methods correlated. The use of both MS and DAD results in a powerful tool for quantifying this important biogenic component of the particulate iron pool.     

On the two-phase Stefan problem with interfacial energy and entropy

Archive for Rational Mechanics and Analysis -     

Corrigendum to: “Clifford Theory of a Finite Group that Contains a Defect 0 p-Block of a Normal Subgroup”

At some point, after publication, the author realized that the proof of [3 Harris, M. E. (2013). Clifford theory of a finite group that contains a defect 0 p-block of a normal subgroup. Comm. in Alg. 41:3509–3540.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar], Theorem 5.2] is incorrect. This proof incorrectly adapts the proof of [1 Broué, M. (1990). Isométries parfaites, types de blocs, cégories dérivees. Aérisque 181–182:61–92. [Google Scholar], Theorem 4.8] since [3 Harris, M. E. (2013). Clifford theory of a finite group that contains a defect 0 p-block of a normal subgroup. Comm. in Alg. 41:3509–3540.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar], (5.5)] is incorrect. Using the same proof outline, we correct the proof of [3 Harris, M. E. (2013). Clifford theory of a finite group that contains a defect 0 p-block of a normal subgroup. Comm. in Alg. 41:3509–3540.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar], Theorem 5.2].     

Electron spin resonance and structure of the ionic radical, ·PO3 =

It is shown that the ionic radical, ·PO₃ ⁼, is formed by the action of γ-rays on disodium ortho-phosphite pentahydrate. The hyperfine coupling to the ³¹P nucleus has principal values of 1967, 1514 and 1513 Mc/s and is consistent with a pyramidal ion having OPO angles of 110°.     

Hans Lieb zum 60. Geburtstag

Ohne Zusammenfassung