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Single crystals of Sr0.5CuZrSe3 (I), Ba0.5CuZrSe3 (II), SrCuYSe3 (III), and BaCuYSe3 (IV) are prepared by solid state reactions of stoichiometric amounts of Cu or Cu2Se (in case of (III)), Ba or BaSe (in case of (II)), and the remaining elements (sealed silica ampoules, 1.

Two novel routes to the acylphloroglucinol rhodomyrtone (1) which has antibiotic properties are presented. In the first route an ortho-quinone methide, generated from dioxaborinine 23, is reacted with syncarpic acid (10) leading to xanthenedione 25. Cleavage of the methyl ether functions led to the known rhodomyrtone precursor 16. In the second route the bis-ester derivative 28 of trihydroxybenzaldehyde 26 is condensed with syncarpic acid (10) to give tricyclic hemiacetal 29. Acetalization and cuprate addition to the enone function led to bis-ester 32 which gave rhodomyrtone (1) by TiCl4-induced regioselective Fries rearrangement.

In this article strategies for the design and synthesis of natural product analogues are summarized and illustrated with some selected examples. Proven strategies include diverted total synthesis (DTS), function-oriented synthesis (FOS), biology-oriented synthesis (BIOS), complexity to diversity (CtD), hybrid molecules, and biosynthesis inspired synthesis. The latter includes mutasynthesis, the synthesis of natural products encoded by silent genes, and propionate scanning. Most of the examples from our group fall in the quite general concept of DTS. Thus, in case an efficient strategy to a natural product is at hand, modifications are possible at almost any stage of a synthesis. However, even for compounds of moderate complexity, organic synthesis remains a bottle neck. Unless some method for predicting the biological activity of a designed molecule becomes available, the design and synthesis of natural product analogues will remain what it is now, namely it will largely rely on trial and error.

MoS2 single-layered ultrasmall nanoplates embedded in carbon nanowires are prepared by a scalable electrospinning process using a DMF solution of (NH4)2MoS4 and polyvinylpyrrolidone followed by calcination (alumina crucible, 1.

Size effects in ionic systems are of extraordinary importance for ion transport as well as mass storage. This constitutes the field of nanoionics. Even though the impact of size can be manifold, the interfacial symmetry break and its consequence of carrier redistribution is to the fore. The contribution goes beyond the mesoscopic case, where any contribution of unperturbed bulk defect structure has disappeared, and extrapolates into the regime of atomistic sizes. Even though these extrapolations represent pure thought experiments, much can be learned from them. They refer to the transition of heterolayered systems to layered crystals, of composites to mixed crystals as well as of nanocrystalline state to the amorphous state. Resulting effects on thermodynamics, transport and storage are discussed.

The spectroscopic data for all isomers [(III)-(V)] and [(VII)-(IX)] are interpreted by DFT methods.

A new open-framework fluoride pyrochlore phase, FeF3·0.5H2O, is prepared from a mixture of Fe(NO3)3·9H2O and single-wall carbon nanotubes suspended in [bmim]BF4 or 1-decyl-3-methylimidazolium tetrafluoroborate (100 °C, 12 h).

A novel strategy to N-Boc-N-methyl--tryptophans (abrine derivatives) was developed that relies on the palladium-catalyzed annulation of ortho-iodoanilines 12 with either N-Boc-N-methyl-propargylglycine 16 or aldehyde 11. Both 11 and 16 can be prepared from d-serine. An alternative route to propargylglycine 16 utilizes an enantioselective propargylation reaction of glycine imine 17.

A systematic defect chemical analysis of Li2O2 provides crucial thermodynamic and kinetic information on the operation of Li—O2 batteries.

By using calcium fluorite and barium fluorite as test materials, we demonstrated that homovalent "dopants" can greatly affect ionic conductivity through locally changing the defect density. Whilst this doping is a state-of-the-art effect in the case of dopants that replace native ions of different charge (heterovalent dopants), it is a rather surprising effect at a first glance for substitutional dopants of the same charge; here, the phenomenon is not electrostatic, but elastic in nature. As a consequence of size mismatch, the smaller Ca atoms in the BaF(2) lattice favored the formation of interstitial sites that were located close to the Ca atoms, whilst doping larger Ba species into the CaF(2) phase favored vacancy formation. In terms of conductivity, and in agreement with the different mobilities, the first doping effect was favorable, whilst the other decreased conductivity. The concentration effects were formalized by a heterogeneous Frenkel reaction that was distinguished from the mean Frenkel reaction by additional (elastic) trapping that became more pronounced the lower the temperature. It was very revealing to relate this phenomenon to CaF(2)-BaF(2) multilayers and composites. In very general terms, these effects in the solid solutions were understood as being the atomistic limit of the interfacial charge-transfer that occurred at the hetero-interface of the crystallites or films, and reflected the transition from heterogeneous doping (higher-dimensional doping) to homogeneous doping (zero-dimensional doping).

A series of 4-formyl esters 8a–d was prepared by Michael addition of an enamine with ethyl acrylate. A subsequent condensation with 2-bromobenzylamines 3 gave rise to cyclic enamides 9aa–dd. In a Heck cyclization reaction tricyclic isoindoles 10aa–dd were formed in good yields.

Three unusual alkylhydrazide natural products, named hydrazidomycin A (Ia), B (Ib), and C (Ic), are isolated from the chloroform extract of a Streptomyces atratus culture.

A route towards phenylene-thiophene macrocycles (IV) via oxidative thiophene coupling under pseudo-high dilution conditions is reported.

The specific Li-ionic conductivities of the title compounds and their temperature dependences are measured by impedance spectroscopy using different electron-blocking and ion-blocking electrode systems between 160 and 550 K.

In this article it is shown how the phenomenological transport parameters measured on a mixed conducting solid oxide fuel cell (SOFC) cathode are related to the underlying fundamental quantities, such as bulk defect concentrations and mobilites, and surface reaction mechanism and corresponding equilibrium exchange rate. Complications due to charged oxygen adsorbates and arising under an applied dc bias are discussed. Dense thin-film microelectrodes are shown to serve as valuable model systems for achieving a mechanistic understanding and obtaining reliable experimental data. Keywords: solid oxide fuel cell; cathode; mixed conductor; equivalent circuit; microelectrodes; oxygen incorporation mechanism; adsorbate coverage; current-voltage-curves; modeling

A superfine expanded graphite fiber material is prepared by fast thermal decomposition of an intercalate of composition C2F·xClF3 (quartz tube, 500 °C).

Li(H2O)2[Zr2(PO4)3] is synthesized by hydrothermal reaction of ZrCl4, Li2B4O7, and H3PO4 (HCl, H2O, pH 1, 180 °C, autoclave, 8 d; 60% yield).

Black, shiny needles of the title compound are prepared by melting a mixture of Cu, CuCl, S, and Bi2S3 (1120 K, tempering at 570 K for 14 d).

The first kinetic resolution of allylic trifluoroacetimidates is achieved by using planar chiral palladacycles as catalysts.

A new bafilomycin-type macrolide, named hygrobafilomycin (6), was isolated by a bioassay-guided selection and fractionation from a terrestrial actinomycete, Streptomyces varsoviensis, along with three known derivatives, bafilomycin D (3), C1 (4) and C2 (5). The structure of hygrobafilomycin was fully established by MS and NMR analyses, revealing a hygrolidin-bafilomycin hybrid with an unusual monoalkylmaleic anhydride moiety. Hygrobafilomycin (6) shows strong antifungal, antiproliferative and cytotoxic activities. In a panel of 40 tumor cell lines, compound 6 shows high cytotoxic potency (mean IC(50)=5.3 n).

The ester (I), readily available in 5 steps from (-)-carvone, is used as starting material in the sequence.

The new title compounds are prepared by reaction of Li3PO4, Li2O, and LiCl or LiBr (gold crucible in an evacuated quartz tube, 723 K, 5 d).

It is discovered that hex-5-yne-1,4-diols of type (I) undergo metal-catalyzed Meyer—Schuster rearrangement followed by an intramolecular Michael addition to yield 2,5-disubstituted tetrahydrofurans.