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Recent theoretical and experimental progress on the study of ferrotoroidic materials is reviewed. The basic field equations are first described and then the expressions for magnetic toroidal moment and toroidization are derived. Relevant materials and experimental observation of magnetic toroidal moment and toroidal domains are summarized next. The thermodynamics of such magnetic materials is discussed in detail with examples of ferrorotoidic phase transition studied using Landau modelling. Specifically, an example of application of Landau modelling to the study of toroidocaloric effect is also provided. Recent results of polar nanostructures with electrical toroidal moment are finally reviewed.

Ruthenium(0) complexes modified by CyJohnPhos or RuPhos catalyze the successive C-C coupling of acetylenic aldehydes with α-ketols to form [4+2] cycloadducts as single diastereomers. This method enables convergent construction of type II polyketide ring systems of the angucycline class.

The title benzothiazepines are synthesized by reaction of various substituted aminobenzenethiols with enolizable heterocyclic ketones.

Upon exposure of 3,4-benzannulated 1,5-diynes (benzo-endiynes) to α-ketols (α-hydroxyketones) in the presence of Ru(0) catalysts derived from Ru3(CO)12 and RuPhos or CyJohnPhos, successive redox-triggered C–C coupling occurs to generate products of [4 + 2] cycloaddition. The proposed catalytic mechanism involves consecutive alkyne-carbonyl oxidative couplings to form transient oxaruthanacycles that suffer α-ketol mediated transfer hydrogenolysis. This process provides a new, convergent means of assembling Type II polyketide substructures.

The reaction of vinylhetarenes with N-Boc protected aryl aldimines delivers the products with moderate to excellent diastereoselectivities and moderate to high enantioselectivities.

The CAN-catalyzed cycloaddition of nitriles with NaN3 is advantageous with regards to short reaction times, easy work up, and high yields.

The publication represents a revision of previously published data stating the formation of substituted 1,3-thiazines instead of substituted 2-thioxothiazolidine-4-alkanoates upon base-mediated cyclization of allyldithiocarbamates.

The new compound banganxanthone C (I) is isolated from the leaves of Garcinia polyantha together with five known compounds.

5,6-Diphenyl 1,2,4-triazine-3-thiol (III) was synthesized from alpha-diketone benzyl (II); II in turn was synthesized from benzoin (I). III on reaction with 1-chloro-2,3-epoxy propane yielded 3-[(oxiranyl methyl)thio]-5,6-diphenyl 1,2,4-triazine (IV). IV was converted to 3-[5,6-diphenyl-1,2,4-triazine-3-yl thio]-3-substituted propanols (V) on reaction with aryl amines. These compounds were screened for their anti-inflammatory activity in albino rats with carrageenin induced paw oedema. Two compounds, Ve and Vl, exhibited significant anti-inflammatory activity compared to the standard, phenylbutazone, with high ALD50 values.

Review: use of water as the best green solvent for various chemical and biological proesses and its superiority over other solvents; 20 refs.

The alkylation procedure is extensively investigated by preparation of 64 different products.

A series of triazoles (III) (9 examples) is readily synthesized by a Huisgen 1,3-dipolar cycloaddition reaction of alkynes (II) with azide (I), which is chemoenzymatically prepared starting from D-xylose.

The conversion of o-vinyl substituted N-Boc-N-acetyl anilines to enecarbamates and subsequent Diels—Alder reaction in the presence of enantiopure BINOL as chiral source is developed.

A variety of new benzopyranobenzothiazepines (III) (12 examples) are synthesized and evaluated for their antimicrobial activities.

The ecofriendly procedures can be regarded as new methods for the preparation of pharmaceutically relevant phenylacetimidamides (IV), phenylacetamides (V) and α-amino acid derivatives (VI).

We present an overview of unconventional phenomena arising close to ferromagnetic and ferroelectric quantum phase transitions. The applicability and potential breakdown of traditional field theories of quantum criticality and the emergence of a multiplicity of critical fields in particular will be discussed.

The purple-coloured iron peroxo complex [Fe(III)EDTA(η2-O2)]3− as a novel reagent system for Pd-catalyzed decarboxylative ortho-acylation of acetanilides with α-oxocarboxylic acids at room temperature in aqueous media has been realized. This reaction provides an effective access to ortho-acylacetanilides under mild conditions.

A simple and highly efficient microwave-assisted synthesis of a library of pyrimidothiazolopyrimidinedione (VII) and related thione derivatives (IX) as potential antitubercular agents is given.

A click chemistry approach is used for the synthesis of novel 1H-1,2,3-triazole tethered isatin conjugates (III) which are evaluated for their cytotoxicity against four human cancer cell lines.

Derivatives (IVb), (IVd) and (IVi) exhibit HIV-RT inhibition and show better activity against K1 strains of P.

The first examples are described for the catalytic enantioselective reductive coupling of alkenylazaarenes.

Cu-nanoparticulates in Guar-gum at room temperature were investigated for the first time as a recyclable catalytic system in organic synthesis. The catalytic potential of these materials were evaluated in the Huisgen [3 + 2]-cycloaddition of azides and alkynes without additives under ambient conditions which offers several advantages, viz. high yields, clean reactions, short reaction times, recyclability of the catalyst and a simple workup procedure.

A series of 3,6-epoxy[1,5]dioxocines, e.g. (III), are synthesized and evaluated for their antifilarial activity against adult parasites of human lymphatic filarial parasite Brugia malayi.

A novel dibenzylamide-containing chiral diene ligand is used in enantioselective arylation reactions of several β-substituted nitroarenes with arylboronic acids (II).

The synthesis of hitherto unknown pyridyl-substituted benzopyran derivatives is achieved in moderate to high yields involving the introduction of a pyridyl moiety in the benzopyran system as the key step.

Ferroics are materials with two or more “orientation” states with the ability to switch between them via an applied field. Based on spatial inversion and time reversal symmetry, there are four types of primary ferroics: ferroelectrics described by polarization P (a polar vector with broken spatial inversion symmetry), ferromagnets described by magnetization M (an axial vector with broken time reversal symmetry), ferrotoroidics described by torodization T (an axio-polar vector with both spatial inversion and time reversal symmetries broken) and ferroelastics described by strain e (a symmetric second rank polar tensor with neither spatial inversion nor time reversal symmetry broken but with broken rotational symmetry). Crystals exhibiting simultaneous ferroelectricity and magnetism are called magnetoelectrics. We analyze the magnetic symmetry of one- and two-dimensional (1D and 2D) multiferroics and enumerate 1D and 2D magnetoelectric point groups. We study a representative phase transition to such a point ...

An efficient methodology employing copper nanoparticles for the preparation of 2-naphthol condensed 1,3-oxazinone derivatives employing one-pot condensation reaction in the presence of K2CO3 and copper nanoparticles in PEG-400 is described which offers several advantages, viz. high yields, clean reaction, short reaction times, recyclability of the catalyst and simple workup procedure. PEG-400 was found to be the best solvent out of a range of solvents examined for this scheme. Moreover, PEG could stabilize the nanoparticles from oxidation and thus could increase the catalyst efficiency by escalating the TON (Turn over Number) and TOF (Turn over Frequency) of the catalyst, making the protocol greener, ecofriendly and environmentally benign.

Compounds (IIIa) and (IIIb) exhibit anti-inflammatory activity comparable to that of ibuprofen, and some of the synthesized compounds, e.g. (VI), show moderate anticancer activity against five human cancer cell lines.

The compounds (III) and (IV) are screened for their antibacterial activity against both types of Gram-positive and Gram-negative bacteria.

Synthesis and in vitro cytotoxic evaluation of a series of N-alkylbromo (III) and N-alkylphthalimido-isatins (V) are reported.

The title compounds (III) are evaluated for their cytotoxicity against the human cancer cell lines SF-295, A-549, PC-3, Hep-2, HCT-15 and MCF-7.

Compared to conventional solvents, [bmim]BF4 significantly accelerates the reaction of acid (I) with aromatic aldehydes.

The biological activity of the newly synthesized compounds (III), (V), and (VII) is evaluated.

Recently, greenhouse gas emissions have been of great concern globally. Ruminant livestock due to production of methane during normal fermentation in the rumen contributes substantially to the greenhouse effects. During the recent decade, a paradigm shift has been initiated whether plant secondary metabolites (PSM) could be exploited as natural safe feed additives alternative to chemical additives to inhibit enteric methanogenesis. More than 200,000 defined structures of PSM have been known. Some plants or their extracts with high concentrations of bioactive PSM such as saponins, tannins, essential oils, organosulphur compounds, flavonoids and many other metabolites appear to have potential to inhibit methane production in the rumen. The possible mechanisms and effects of many PSM on rumen methanogenesis are not clearly understood. Saponins may decrease methanogenesis through the inhibition of rumen protozoa and in turn may suppress the numbers and activity of methanogens. Although the direct effect of saponins on methanogens has not been demonstrated, saponins might inhibit methanogens at high doses. Tannins may inhibit the methanogenesis directly and also via inhibition of protozoal growth. Essential oils, organosulphur compounds and flavonoids appear to have direct effects against methanogens, and a reduction of protozoa associated methanogenesis probably plays a minor role for these metabolites. The chemical structure and molecular weight of the PSM and chemical composition of diets dependent upon the different feeding regimes may influence the effects of PSM on methane production. Although PSM may negatively affect nutrient utilization, there is evidence that methanogenesis could be suppressed without adversely affecting rumen fermentation, which could be exploited to mitigate methane emission in ruminants.

C 22 H 25 N 3 cristallise dans P2 1 /c avec a=9,122, b=22,108; c=9,165 A, β=102,20 o , Z=4; affinement jusqu'a R=0,043.Le substituant azote, dans le methylphenyl, presente l'hybridation sp 2

The sodium salt of 4-amino-3-cyanopyrazolo[3,4-d]pyrimidine (1) was condensed with (2-acetoxyethoxy)methyl bromide (2) to provide the corresponding protected acyclic nucleoside, 4-amino-3-cyano-1-[(2-acetoxyethoxy)methyl]-pyrazolo[3,4-d]pyrimid ine (3). Treatment of 3 with sodium methoxide in methanol provided a good yield of methyl 4-amino-1-[(2-hydroxyethoxy)methyl]pyrazolo[3,4-d]pyrimidine-3- formimidate (4). Treatment of the imidate (4) with sodium hydrogen sulfide gave the thiocarboxamide derivative 5. Aqueous base transformed 4 into 4-amino-1-[(2-hydroxyethoxy)methyl]pyrazolo[3,4-d]pyrimidine-3- carboxamide (6) in good yield. Treatment of 5 with mercuric chloride furnished the toyocamycin analogue 7. Evaluation of compounds 1, 3-7 revealed that only the heterocycle (1) and the thiocarboxamide acyclic nucleoside (5) were active. Compound 5 was the more potent with activity against human cytomegalovirus and herpes simplex virus type 1.