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A facile method for the synthesis of a variety of β-carbolines and their natural products such as norharmane (2a), harmane (2b), eudistomins I, N, T, and U (6, 7, 9 and 10, respectively) has been successfully developed via a decorboxylative aromatization tool by employing N-chlorosuccinimide (NCS) as a mild and efficient reagent. Gratifyingly, this reagent system proceeds in a one-pot manner and converted all the tetrahydro-β-carboline acids into their corresponding decorboxylative aromatic products with good to excellent yields. Additionally, this system works well in the case of tetrahydro-β-carboline esters to produce their aromatic partners in high yields.

The review is devoted to systematic description of results on relaxation of magnetization in magnetically ordered crystals previously obtained by the authors. The ideas of the phenomenological theory of magnetism formulated by Landau and Lifshitz are analyzed. A general method of constructing the dissipation function for both magnetically ordered systems and paramagnets is described. In the case of magnetically ordered systems the dissipation of exchange and relativistic nature is considered. It is found that for constructing the dissipation function it is necessary to take into account not only the symmetry of a crystal, but also the laws of conservation of magnetization. It is shown that in the case of a ferromagnet, the ground state is characterized by a continuous degeneracy parameter; the Landau-Lifshitz relaxation term gives qualitatively incorrect results (abnormally large attenuation of spin waves). According to the proposed method the spectra of spin waves and their attenuation were calculated and analyzed for ferromagnets with uniaxial, tetragonal and cubic symmetry as well as for two-sublattice uniaxial ferrites. It was found that the relaxation of the magnetization vector has a two-step character in ferromagnets and a multistep character in ferrites. In ferrites, the fastest process is the relaxation of length of the antiferromagnetic vector. It is shown that this relaxation is caused by the exchange interaction between sublattices of a ferrite and is enhanced by the exchange interactions within the sublattices. The relaxation of the total magnetization of a ferrite is much slower and, as in the case of a simple ferromagnet, is described by non-uniform exchange interactions and relativistic interactions. The results obtained are in a good agreement with recent experimental data.

Depending on the substituent on the exocyclic sulfur, 5-allyl-6-thioxopyrazolo[3,4-d]pyrimidin-4-one (I) can be anellated on halogenation as either thiazoline or oxazoline ring.

The title compounds (III) are synthesized for the first time by acylation of cyclopentane-1,3-dione (I) with perfluorocarboxylic acids in the presence of CDI or with perfluorocarboxylic anhydrides in the presence of imidazole.

An efficient method has been developed for the preparation of halo derivatives of 6-methyluracil by employing oxidative halogenation. Elemental halogens and potassium halides were used as the halogenating agents, while NaNO3 and H2O2 were used as the oxidizing agents. Iodination of 6-methyl-uracil leads to 5-iodo-6-methyluracil as the single reaction product, while bromination or chlorination lead to 5-halo-6-methyluracil, 5,5-dihalo-6-hydroxy-6-methyl-5,6-dihydrouracil, or their mixture depending on the acidity of the medium and the ratio of the substrate and reagents. Bromination of 5-chloro-6-methyluracil leads to 5-bromo-5-chloro-6-hydroxy-6-methyl-5,6-dihydrouracil, while chlorination of 6-methyl-, 5-bromo-6-methyl-, and 5-chloro-6-methyluracils using gaseous chlorine yields 5,5-dichloro-6-hydroxy-6-methyl-5,6-dihydrouracil.

Reaction of N-ethylpyrazinocarbazole (IIIa) with acetylene derivatives (IV) in MeCN affords the title diazocinocarbazoles (V), which are representatives of a previously unknown heterocyclic system.

This is a review of experimental and theoretical research on diamagnetic domains in normal metals. Considerable attention is devoted to a new, effective method for studying domain structures: muon spectroscopy based on measuring the induction using the precession frequency of muons in a magnetic field. A number of phenomena which arise in states with magnetic domains, including unusual magnetostriction and hysteresis in the de Haas-van Alphen effect, are discussed. The mechanism of nonlinearity in the propagation of low-frequency electromagnetic waves in metals with strong magnetism of their conduction electrons is examined.

With the rapidly growing demand for bandwidth in wireless communication systems and increasing frequencies of operation of electronic devices, in recent years resurgence in scientific interest in highly anisotropic hexagonal ferrites has been noted. This interest stems in part from a number of emerging applications that pose significant materials challenges that cannot be addressed using traditional rf and microwave ferrite materials. In this manuscript, several specific applications that could benefit from the unique properties of hexagonal ferrites are discussed. Fundamental principles of operation, materials requirements, as well as unique device design and modeling challenges are reviewed. Applications of textured magnetically uniaxial hexagonal ferrite composites in microwave and mm-wave non-reciprocal ferrite control devices are discussed. Applications of textured magnetically planar hexagonal ferrite composites as antenna and electronic bandgap metamaterial substrates, rf inductors and transformers, and electromagnetic interference suppression devices are reviewed. Suggestions on directions for future research and development are provided.

Electrophilic heterocyclization of 3-allylthiotriazoles (I) by action of bromine or iodine results in the regioselective formation of thiazolotriazolium salts [cf.

The new linear polyconjugated compounds (I) and (II) show strong luminescence in solutions as well as in the solid state and exhibit electroluminescent properties.

The title compounds (x = 0.25, 0.5, 0.75, 0.9) are prepared by solid state reaction of Al(NO3)3, H3BO3, K2CO3, and Rb2CO3 (various heat treatments between 400 and 850 °C for 7—48 h).

Amidines (V) are interesting and promising synthon for the synthesis of polyheterocyclic systems such as the title pyridothienopyrimidines.

The literature data on the synthesis and chemical The literature data on the synthesis and chemical properties of fluoro-substituted properties of fluoro-substituted b-diketones and -diketones and b b-tri- ketones are generalized. The bibliography includes 312 ketones are generalized. The bibliography includes 312 references references..

Mechanisms of ozonolysis of unsaturated carbonyl compounds and alcohols were considered, and the effects of the substrate structure and reaction conditions on the product composition were analyzed.

The present review covers general aspects related to the metabolism of organic compounds, primarily, of biologically active azaheterocycles used as drugs. Compounds of this type occupy a dominant place among known drugs. Data on the main chemical processes determining the pathways of principal biotransformations, such as redox reactions, hydrolysis, alkylation, acylation, various conjugations, isomerizations, and condensations, are summarized. The metabolisms of heterocycles is considered based on the ring size of the substrate.

Aryl-substituted formylpyridinones are synthesized from enaminoamides, and transformed into several different naphthyridinones as well as related tricyclic compounds.

Novel isoxazolylchromenones (V) are synthesized via Baker—Venkataraman transformation of esters (III) and subsequent microwave-assisted reaction of the obtained propanediones (IV) with hydroxylamine.

Most of the title compounds (VII) exhibit moderate antibacterial activities, but only compound (VIIc) possesses moderate antifungal activities.

Thio- and selenopyrylium salts undergo simultaneous oxidation, leading to the corresponding benzoylselenophene or benzoylthiophene, and reduction reactions leading to 4H-selenopyran or 4H-thiopyran In the presence of water and triethylamine.