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Singlecrystals of the charge-transfer salt picene/2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethanehave been grown using physical vapor transport. The crystal structurewas determined using single-crystal X-ray diffraction. It was foundthat the crystals grow in a 1:1 molecular ratio and adopt a monoclinicstructure with alternate stacking. Both X-ray data and Raman measurementsshow that the grown crystals are of good quality. From structure andinfrared data, the charge transfer between acceptor and donor moleculeswas estimated to be approximately 0.14–0.19 electron. Transportmeasurements indicate a nonmetallic ground state with an activationenergy of 0.6 eV. The supporting density functional theory calculationson molecular model systems as well as on crystalline structures confirmthe amount of charge transfer and provide first insights into theelectronic structure of the new material. [ABSTRACT FROM AUTHOR]

Promising membrane transport and separation systems for selected dicarboxylic, α-hydroxy- and α-amino acids based on thiacalixarene platform have been developed. For the first time, p-tert-butyl thiacalix[4]arenes functionalized at the lower rim with aminophosphonate fragments have been obtained and characterized. As was established by UV-vis spectroscopy, membrane extraction and HPLC, the substitution of amino groups by α-aminophosphonate units significantly enhances the selectivity of host molecules that bind to aspartic and glycolic acids. The aminophosphonate compounds synthesized can be used in the development of sensors and systems employed in the purification and separation of organic acids. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Using 3β-hydroxychol-5-en-24-oic acid (4) as starting material, the diastereoisomeric allylic alcohols (24E)-26-hydroxydesmosterol (2) and (24Z)-26-hydroxydesmosterol (3) have been synthesised in six steps with 67% and 12% overall yield, respectively. Both of these isomers are found in newborn mouse brain where sterol synthesis is high. Unlike desmosterol (1), neither of these isomers is a ligand to the liver x receptors and thus represents a novel biological deactivation mechanism avoiding cholesterol synthesis. [Copyright &y& Elsevier]

We describe the efficient iron-mediated total synthesis of clausine O, clausine H (clauszoline-C) and anti-HIV active 7-methoxy- O-methylmukonal and clausine K (clauszoline-J). Consecutive C-C and C-N bond formations between 3-methoxy-4-methylaniline and a cyclohexadienyliumiron complex salt afforded 2,7-dimethoxy-3-methylcarbazole, which served as common intermediate en route to the four alkaloids. [ABSTRACT FROM AUTHOR]

44 species of lichen-forming, lichenicolous and non-lichenized fungi are reported from the Novgorod Region, 34 of them are new to the region. Leptogium biatorinum is new to European Russia. Nephromopsis laureri is red-listed in Russian Federation and should be included in the Red Data Book of the Novgorod Region. Most noteworthy records are briefly discussed. Two species - Collema callopismum and Hertelidea botryosa - are excluded from the lichen list of the Novgorod Region. [ABSTRACT FROM AUTHOR]

Using an iron-mediated construction of the carbazole framework, the first synthesis of streptoverticillin is described and the absolute configuration of the natural product is confirmed. The synthesis exploits a novel oxygen-mediated aromatization of tricarbonyliron-coordinated dihydrocarbazoles. Moreover, non-natural (R)-streptoverticillin is prepared for comparison. [ABSTRACT FROM AUTHOR]

1,3-Dienic δ -sultones 4,6-diaryl-[1,2]oxathiine 2,2-dioxides were synthesized via a one-step reaction of arylalkynes with dioxane sulfotrioxide. The reactivity of various alkynes in this reaction was investigated. The resulting sultones were brominated with Br2 or N-bromosuccinimide regioselectively α to sulfur and subsequently coupled with phenylacetylene using Sonogashira conditions. [image omitted] [ABSTRACT FROM AUTHOR]

The condensation of do-, hexa-, octadecan-1-amines with bromo- and nitrobenzaldehydes yielded a series of Schiff bases in good yields. Subsequent reaction of these compounds with dioctylphosphine oxide yielded phosphorylated azomethines and some were characterized using X-ray crystallography. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. All of the synthesized compounds were tested for their antibacterial and anti-Candida activity. A number of the compounds exhibited antimicrobial activity comparable to that of the commercially available drugs, ciprofloxacin and clotrimazole. [ABSTRACT FROM PUBLISHER]

Stable phosphonium salts were synthesized by the phosphorylation of a series of ω-haloalkylcarboxylic acids with triphenylphosphine. In a second step the resulting phosphonium salts have been treated with 1 M aqueous solution of sodium hydroxide to form the corresponding carboxylate phosphabetaines. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and X-ray crystallographic studies. Their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. [ABSTRACT FROM PUBLISHER]

Direct anodic oxidation of 2,4-dimethylphenol yields an unusual spiropentacyclic scaffold. An intermediate was isolated and structurally elucidated which strongly supports the postulated mechanism for the stereoselective formation of this spirolactone moiety. Additionally, we report an ameliorated protocol for the rearrangement to the spirolactone system. [ABSTRACT FROM AUTHOR]

Isomeric pyrimidinophanes containing uracil moieties and nitrogen atoms in bridges have been synthesized and characterized by a variety of methods both in solid and in solution. Unambiguous assignment of mutual arrangement of C(4)pyrO groups at different pyrimidine rings in isomers is made by X-ray diffraction. In solutions the arrangement of C(4)pyrO groups of the isomeric pyrimidinophanes results in different dipole moments. Based on dipole moments simulations mutual orientation of uracil units in isomers is analysed. UV-data are discussed in terms of hypo- or hyperchromic effect. [ABSTRACT FROM AUTHOR]

A synthetic protocol for optically pure (-)-menthylamine, (-)-8-methylmenthylamine, and the novel (-)-8-phenylmenthylamine is presented including a detailed characterization of these compounds and their isocyanates. Key words: amines; aminations; asymmetric synthesis; chirality; chiral auxiliaries. [ABSTRACT FROM AUTHOR]

The chlorination of electron rich iodoarenes with MoCl[sub5] proceeds with methoxycarbonylmethyl as the directing group. The transformation is selective and without loss of the valuable iodo substituent. [ABSTRACT FROM AUTHOR]

Crystal and molecular structure of 1-phenyl-3-benzoylamino-4-benzoylpyrazol-2-in-5-one as a product of the benzoylation of 1-phenyl-3-benzoylaminopyrazol-2-in-5-one was characterised by X-ray single crystal diffraction. It is shown that 1-phenyl-3-benzoylamino-4-benzoylpyrazol-2-in-5-one exists in the solid phase in an NH-tautomeric form, which is stabilised by two intramolecular hydrogen bonds and one intermolecular bond with the solvate dioxane molecule, the latter being used as a solvent for recrystallisation. [Copyright &y& Elsevier]

In a series of three chiral thioureas with a 1-phenylethylamine fragment, none of the homochiral samples forms "true chiral" hydrogen-bonded motifs in the crystal, but forms dimers or chains with local symmetry from the interacting fragments, consistent with the racemic crystal pattern. [ABSTRACT FROM AUTHOR]

We describe an iron‐catalyzed asymmetric oxidative C−C coupling of diarylamines which proceeds at room temperature with air as final oxidant. Using hexadecafluorophthalocyanine‐iron(II) as catalyst in the presence of catalytic amounts of an axially chiral biaryl phosphoric acid, the resulting chiral 2,2′‐diamino‐1,1′‐biaryls are obtained in up to 90 % ee as confirmed by chiral HPLC. A detailed mechanism has been proposed with a radical cation‐chiral phosphate ion pair as key intermediate leading to the observed asymmetric induction. [ABSTRACT FROM AUTHOR]

The acid-base and complexing properties of N,N-bis(O-diethylhydroxyphosphorylmethyl)-N-butylamine (H3L) with divalent metals were investigated in aqueous solution via the potentiometric titration method. The formation of 1:1 species has been established. The structure of complex N,N-bis(O-diethylhydroxyphosphorylmethyl)-N-butylamine with copper(II) was determined using an X-ray diffraction method. [ABSTRACT FROM AUTHOR]

New stable carboxylate phosphabetaines were synthesized by the phosphorylation of trans-aconitic acid by tertiary phosphines. The structures of the isolated compounds were determined by NMR spectroscopy, X-ray single crystal diffraction studies and elemental analysis. [ABSTRACT FROM AUTHOR]

A new family of sterically hindered alkyl(tri-tert-butyl) phosphonium salts (n-CnH2n+1 with n = 2, 4, 6, 8, 10, 12, 14, 16, 18, 20) was synthesized and evaluated as stabilizers for the formation of palladium nanoparticles (PdNPs), and the prepared PdNPs, stabilized by a series of phosphonium salts, were applied as catalysts of the Suzuki cross-coupling reaction. All investigated phosphonium salts were found to be excellent stabilizers of metal nanoparticles of small catalytically active size with a narrow size distribution. In addition, palladium nanoparticles exhibited exceptional stability: the presence of phosphonium salts prevented agglomeration and precipitation during the catalytic reaction. [ABSTRACT FROM AUTHOR]

We describe the synthesis and photophysical properties of tetraarylnaphthidines. Our synthetic approach is based on an iron-catalyzed oxidative C–C coupling reaction as the key step using a hexadecafluorinated iron–phthalocyanine complex as a catalyst and air as the sole oxidant. The N,N,N',N'-tetraarylnaphthidines proved to be highly fluorescent with quantum yields of up to 68%. [ABSTRACT FROM AUTHOR]

The reaction of triferrocenylthiophosphite with elemental sulfur leads to triferrocenyltetrathiophosphate. The molecule of tetrathiophosphate adopts propeller-like all synclinal-conformation of the ferrocenyl fragments respective to the P=S bond. All ferrocenyl groups have nearly ideal eclipsed conformation of the cyclopentadienyl fragments. The Fc3S3P (1), Fc3S3P=O, (2) and Fc3S3P=S (3) demonstrate three reversible and well-separated ferrocenyl-based redox events. The electronic structures of 1–3 have been studied quantum-chemically; the energies and composition of frontier orbitals have been calculated. [ABSTRACT FROM AUTHOR]

Chirality control over the formation of Ni(II) complexes with chiral thiophosphorylated thioureas was achieved via breaking the symmetry of nickel coordination geometry by the introduction of the pyridine ligand, while centrosymmetric meso-complexes are formed from racemic ligands in case of square-planar nickel coordination. Centrosymmetric heterochiral arrangement is observed in crystals of ligands themselves through N–H⋅⋅⋅S hydrogen bonds in intermolecular dimers. Molecular homochirality in tetragonal pyramidal complexes is further transferred to supramolecular homochiral arrangement via key–lock steric interactions. [ABSTRACT FROM AUTHOR]

Herein, we describe a convenient and general method for the oxidation of olefins to ketones using either tris(dibenzoylmethanato)iron(III) [Fe(dbm)3] or a combination of iron(II) chloride and neocuproine (2,9‐dimethyl‐1,10‐phenanthroline) as catalysts and phenylsilane (PhSiH3) as additive. All reactions proceed efficiently at room temperature using air as sole oxidant. This transformation has been applied to a variety of substrates, is operationally simple, proceeds under mild reaction conditions, and shows a high functional‐group tolerance. The ketones are formed smoothly in up to 97 % yield and with 100 % regioselectivity, while the corresponding alcohols were observed as by‐products. Labeling experiments showed that an incorporated hydrogen atom originates from the phenylsilane. The oxygen atom of the ketone as well as of the alcohol derives from the ambient atmosphere. [ABSTRACT FROM AUTHOR]

The tetracyclic pyrido[4,3-b]carbazole olivacine and four of its oxygenated derivatives have been synthesized by a late-stage palladium-catalyzed Heck-type cyclization of the pyrrole ring as a key step. In a test for the inhibition of the growth of Mycobacterium tuberculosis, 9-methoxyolivacine showed the most significant inhibitory activity against Mycobacterium tuberculosis, with an MIC90 value of 1.5 μM. [ABSTRACT FROM AUTHOR]

In this work, we present a new type of amphiphilic membrane-anchoring agents that can be easily obtained by the between terpene myrcene and N-substituted maleimides. The interaction between the compounds and small unilamellar dipalmitoylphosphatidylcholine vesicles was investigated using , microgravimetry, and turbidimetry. The ability of the compounds to embed in the phospholipid membrane was shown to be strongly dependent on the charge of their polar group. The insertion of the compounds studied into the lipid bilayer did not lead to disruption of the dipalmitoylphosphatidylcholine vesicles up to the highest tested drug to lipid molar ratio of 0.5 to 0.6. Low lipid solubilization ability of the compounds as well as their rigid nonplanar structure makes them an interesting alternative to the common membrane-anchoring structural motifs. [ABSTRACT FROM AUTHOR]