Medicinal Plants of the Family Lamiaceae in Pain Therapy: A Review.

Recently, numerous side effects of synthetic drugs have lead to using medicinal plants as a reliable source of new therapy. Pain is a global public health problem with a high impact on life quality and a huge economic implication, becoming one of the most important enemies in modern medicine. The medicinal use of plants as analgesic or antinociceptive drugs in traditional therapy is estimated to be about 80% of the world population. The Lamiaceae family, one of the most important herbal families, incorporates a wide variety of plants with biological and medical applications. In this study, the analgesic activity, possible active compounds of Lamiaceae genus, and also the possible mechanism of actions of these plants are presented. The data highlighted in this review paper provide valuable scientific information for the specific implications of Lamiaceae plants in pain modulation that might be used for isolation of potentially active compounds from some of these medicinal plants in future and formulation of commercial therapeutic agents.

Slow magnetic relaxation in a dimeric Mn2Ca2 complex enabled by the large Mn(iii) rhombicity.

In this paper we present the characterization of a complex with the formula [Mn2Ca2(hmp)6(H2O)4(CH3CN)2](ClO4)4 (1), where hmp-H = 2-(hydroxymethyl)pyridine. Compound 1 crystallizes in the monoclinic space group C2/c with the cation lying on an inversion centre. Static magnetic susceptibility, magnetization and heat capacity measurements reflect a unique Mn(iii) valence state, and single-ion ligand field parameters with remarkable large rhombic distortion (D/kB = -6.4 K, E/kB = -2.1 K), in good agreement with the high-field electron paramagnetic resonance experiments. At low temperature Mn2Ca2 cluster behaves as a system of ferromagnetically coupled (J/kB = 1.1 K) Mn dimers with a ST = 4 and mT = ±4 ground state doublet. Frequency dependent ac susceptibility measurements reveal the slow magnetic relaxation characteristic of a single molecule magnet (SMM) below T = 4 K. At zero magnetic field, an Orbach-type spin relaxation process (τ ∼ 10-5 s) with an activation energy Ea = 5.6 K is observed, enabled by the large E/D rhombicity of the Mn(iii) ions. Upon the application of a magnetic field, a second, very slow process (τ ∼ 0.2 s) is observed, attributed to a direct relaxation mechanism with enhanced relaxation time owing to the phonon bottleneck effect.

{Dy(α-fur)3}n: from double relaxation single-ion magnet behavior to 3D ordering.

The synthesis and magnetostructural properties of a new low-dimensional magnetic system based on α-furoate ligands, {[Dy(α-C4H3OCOO)(µ-(α-C4H3OCOO))2(H2O)3]}n, abbreviated {Dy(α-fur)3}n, are reported. X-ray diffraction experiments results evidence the presence of two different Dy coordination environment types differing only in the position of one of the furoate ligands. The crystallographic structure is formed by polymeric chains along the c-axis, each composed of just one Dy type, coupled within the bc-plane with chains of the same Dy type. These planes, each of them containing only one Dy type, are randomly stacked along the a-axis. The magnetic behaviour was studied by magnetization, static and dynamic susceptibility, heat capacity measurements and ab initio simulations. The directions of the easy axes of magnetization, gyromagnetic values and energy level structures of the two Dy types were obtained from ab initio calculations. {Dy(α-fur)3}n exhibits slow magnetic relaxation dynamics below 10 K. The two Dy types with different coordination environments behave as single-ion magnets, with different thermal activation energies of 80.5(6) K and 32.4(5) K, until they reach, upon cooling, a quantum tunneling (QT) regime. Magnetic diluted samples, substituting Dy by Y, {Y(x)Dy(1-x)(α-fur)3}n, were prepared to study the effect of intercluster interactions. Decreasing the Dy interaction by dilution by 90-95% leaves the activation energy unchanged, but shifts the transition to the QT regime to lower temperatures. At T = 2.4 K the tunneling time constant has been shown to decrease weakly with the field in the x = 0 case, and more strongly for x = 0.9. As the external field increases, quantum tunneling is quenched and a new slow relaxation appears that is identified at high fields as caused by a direct relaxation process. As the temperature is decreased, interchain AF coupling becomes effective and gives rise to the occurrence of an antiferromagnetic 3D order transition at T(N) = 0.66 K. From all the evidence, it is concluded that within each bc-plane Dy ions arrange in chains along the c-direction, having weak uncompensated ferromagnetic spin-canted intrachain coupling and antiferromagnetic interchain coupling.

Synthesis and anti-tuberculosis activity of new hetero(Mn, Co, Ni)trinuclear iron(III) furoates.

New hetero(micro(3)-oxo)trinuclear iron(III) furoates with the general formulas [Fe(2)MO(alpha-Fur)(6)(L)(H(2)O)(2)], where L = THF (1-3), DMF (4-5), M = Mn(2+) (1, 4), Co(2+) (2, 5), Ni(2+) (3, 6) and [Fe(2)MO(alpha-Fur)(6)(3Cl-Py)(3)], where M = Mn(2+) (7), Co(2+) (8), Ni(2+) (9); have been synthesised and investigated by Mössbauer and IR spectroscopies. The X-ray crystal structure has been determined for the 4 and 8 complexes, indicating that they are related to the monoclinic crystal system (P2(1)/n) and have a structure typical of mu(3)-O-bridged trinuclear iron (III) compounds. The (57)Fe Mössbauer spectra of microcrystalline samples of the compounds indicate the presence of high-spin iron (III) (S = 5/2) with a near symmetrical environments. The iron(III)-cobalt(II) containing compounds 2, 5 and 8 displayed MIC values between 0.83 / 4.00 microg/mL.

Donnan-exclusion-driven distribution of catalytic ferromagnetic nanoparticles synthesized in polymeric fibers.

One of the routes to overcome the high instability of metal nanoparticles (MNPs) lies in the use of polymeric materials for their synthesis and stabilization. Besides, one of the most serious concerns associated with the growing production and use of MNPs is the possibility of their uncontrollable escape into the medium under treatment and the environment. A possible solution to this problem could be the synthesis of ferromagnetic MNPs with desired functionality, that might not only prevent their escape by using simple magnetic traps but also allow their recovery and reuse. In our work we report the results obtained by the development of environmentally-safe polymer-metal nanocomposite materials containing polymer-stabilized MNPs (PSMNPs) with properties. This material consists of a functional polymer with immobilized Pd@Co core-shell PSMNPs distributed mainly near the surface of the polymer which makes PSMNPs maximally accessible for reagents in catalytic applications. The material was characterized by different techniques to evaluate the total metal content, the size and the magnetic properties of MNPs and their distribution inside the polymer. All nanocomposites were tested as catalysts in Suzuki cross-coupling reactions between arylboronic acids and aryl halides to produce biphenyls as a reference reaction.