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Eight new isocoumarin glycosides (1-8) were obtained from the solid culture of the wetland soil-derived fungus Metarhizium anisopliae (No. DTH12-10). Their chemical structures were elucidated by analyses of HR ESI-TOF MS, (1)H, (13)C NMR, (1)H-(1)H COSY, HSQC, and HMBC spectra. The absolute configurations were determined by single crystal X-ray diffraction, circular dichroism (CD) spectrum, and chemical derivatization methods. In addition, inhibition of the biofilm formation and the secretion of virulence factor of the new isocoumarin glycosides against Pseudomonas aeruginosa strain PAOA (clinical isolates) were evaluated. The result revealed that compound 1 showed antibacterial activity comparable with (Z)-4-bromo-5-(bromomethylene)-2(5H)-furanone (BF).

A new chromium(II) sulfide, Lu2CrS4, with a novel structure was prepared by a solid-state reaction. The powder X-ray diffraction pattern could be indexed as a tetragonal system, with a = 7.46373(2) A, c = 22.6338(2) A, and space group I42d (No. 122). Rietveld analysis of the pattern provided the crystal structure consisting of CrS6 and LuS6 octahedra sharing edges and apexes and revealed a rock salt superstructure with new cation (vacancy) arrangements. The electrical resistivity indicates semiconducting behavior. The magnetic susceptibility and specific heat measurements showed that the Cr ions are in the high-spin d(4) configuration and that their magnetic moments ordered antiferromagnetically at 55 K. The basic antiferromagnetic structure was determined using powder neutron diffraction data at 10 K. The band structure calculations demonstrate that the densities of states of Cr 3d electrons split into two spin-up eg bands because of Jahn-Teller distortion.

Three new isocoumarin derivatives, mucorisocoumarins A-C, are isolated along with seven known compounds.

Ferroelectric A-site-ordered double perovskite CaMnTi2O6 is prepared from equimolar mixtures of MnTiO3 and CaTiO3 in Au (for single crystals) and Pt capsules (for polycrystalline material) under high-pressure (TRY cubic multianvil press, 1200-1700 °C, 7 GPa, 0.5 h) followed by annealing (N2 atmosphere, 500 °C, 6 h).

Single crystals of the new title compound are synthesized by solid state reaction of Na2CO3, Co3O4, and TeO2 (alumina boat, 1273 K, 4 h).

Eu2AlO3.75N0.1 (I) and EuAl2O4 (II) are synthesized by reaction of Eu2O3, AlN, and Al2O3 with Eu/Al ratios of 2:1 and 1:2, respectively (silica tubes, 1200 °C, 10 h).

Functionalized organozinc substrates are prepared following different metalation strategies and subjected to the reaction with various aryldiazonium salts.

Primary and secondary alkylzinc reagents add to various aryldiazonium salts leading to polyfunctional indoles by means of a [3,3]-sigmatropic shift and subsequent aromatization.

2-O-acetonyl-2-O-hydroxypropyl-β-cyclodextrin, which could be used as a key intermediate for very soluble functional β-cyclodextrin derivatives, was prepared based on the proper oxidation of heptakis(6-O-dimethylthexylsilyl)-2-O-hydroxypropyl-β-cyclodextrin.

A series of triarylantimony dipyrazolecarboxylates was synthesized by the reaction of pyrazolecarboxylic acid with triarylantimony dibromides in the presence of potassium hydroxide. The structures of the title compounds were confirmed by elemental analysis, 1H NMR, IR, and mass spectra. Some of these compounds were found to possess antibacterial activity. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:299–301, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10033

A wide range of polyfunctional aryl and heteroaryl zinc reagents were efficiently prepared in THF by using (TMP)(2)Mg2 LiCl (TMP=2,2,6,6-tetramethylpiperamidyl) in the presence of ZnCl(2). The possible pathways of this metalation procedure as well as possible reactive intermediates are discussed. This experimental protocol expands the tolerance of functional groups and allows an efficient zincation of sensitive heterocycles such as quinoxaline or pyrazine. The zincated arenes and heteroarenes react with various electrophiles providing the expected products in 60-95 % yield.

Four new BINOL-based thiazole (thiadiazole) thioether ligands (S)-1, (S)-2, (S,S)-3 and (S)-4 were prepared. When their catalytic effectiveness was tested, good results (up to 93% ee and 97% yield) were obtained in the asymmetric addition of diethylzinc to aldehydes while poor results were obtained in the asymmetric conjugate addition of diethylzinc to enones.

By using indirect reductive amination and condensation, two types of aminonaphthol and imine ligands based on 3-substituted binaphthol have been synthesized, respectively. When their catalytic effectiveness was tested by the ethylation of aldehydes with diethylzinc, titanium tetraisopropoxide was found essential to get good results with ee up to 90%.

A new modified BINOL, ( S )-3-[(1 H -1,2,4-triazol-1-yl)methyl]-1,1′-binaphthol, was prepared. In the presence of titanium tetraisopropoxide, this ligand showed moderate catalytic properties for the asymmetric addition of diethylzinc to aldehydes. By treating rac -3-[(1 H -1,2,4-triazol-1-yl)methyl]-1,1′-binaphthol with excess titanium tetraisopropoxide, a novel trinuclear titanium(IV) complex was obtained. A C 3 axis along Ti1–Ti2–Ti3 is present in the molecule.

Two new ligands (S,S)-3-(1,1′-bi-2-naphthol-3-yl)-5,6,7,8-tetrahydro-1,1′-bi-2-naphthol [(S,S)-1] and (S)-3-(morpholin-4-ylmethyl)-H4-BINOL [(S)-2] have been synthesized via Suzuki cross-coupling reaction and a Mannich-type reaction, respectively. In the presence of titanium tetraisopropoxide, 0.8 mol % of ligand (S,S)-1 catalyzed the asymmetric addition of diethylzinc to aromatic aldehydes in good yield and with high enantioselectivity.

By using a direct ortho-lithiation, the ligands (S)-3-methoxymethyl-1,1′-bi-2-naphthol [(S)-1], (S)-3,3′-bis(methoxymethyl)-1,1′-bi-2-naphthol [(S)-2], (S)-3-(quinolin-2-yl)-1,1′-bi-2-naphthol [(S)-3] and (S)-3,3′-bis(quinolin-2-yl)-1,1′-bi-2-naphthol [(S)-4] have been synthesized. (S)-1 and (S)-3 show moderate catalytic properties for the asymmetric diethylzinc addition to aromatic aldehydes.

Fourteen new TCNQ (7,7,8,8-tetracyanoquinodimethane) simple salts of the type ML(TCNQ)2 and complex salts of the type ML(TCNQ)3, where M = nickel or copper and L = macrocyclic ligands, have been synthesized. The IR spectra of all the complex salts showed a strong absorption band about 2300–4000 cm−1 indicating the charge transfer between TCNQo and TCNQ−. The interaction between TCNQ− caused the activation of TCNQ IR non-active Ag vibrations demonstrating the charge transfer between TCNQ− species. The electronic absorption spectra gave two strong absorption bands at about 16.5 × 103 and 26.5 × 103 cm− caused by the local excitation in TCNQo or TCNQ−. The ESR spectra did not show a clear interaction between the copper ions. Based on these facts one could imagine segregated stacks of the metal complex cations and od TCNQ− anions. This one-dimensional structure of TCNQ− resulted in a good conductivity in the order of σRT = 10−1 – 10−4 ohm− cm− for some of these complex salts.