A pincer-like chiral auxiliary strategy for synthesizing various optically active α,α-disubstituted amino acids in high yields with excellent enantioselectivities is described.

For many years it has been realized that ser globulin is not a single homogeneous protein, comprises a variety of proteins which have 4 ferent physical, chemical, and physiological p perties. The salt fractionation methods that h been 'used for many years do not yield fracti which are sharply distinguished one from anot in any properties. A striking example is that the fractionation of diphther...

In the structure of the title coordination polymer, {(C(8)H(20)N)[Sn(3)(CH(3))(9)(SO(4))(2)]}(n), each of the three Sn(IV) atoms is coordinated in a trigonal-bipyramidal manner by three methyl groups in the equatorial plane and by two O atoms of SO(4) (2-) anions in the axial positions. The μ(3)-bridging mode of the sulfate anions leads to the formation of corrugated anionic layers parallel to ...

für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution 4.0 International License. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Creative Commons Namen...

The title organic-inorganic hybrid compound, {(C7H20N2)[BiCl5]} n , consists of distorted corner-joined [BiCl6] octa-hedra forming zigzag polymeric anionic chains parallel to [001], separated by columns of heptyl-enedi-ammonium cations. The asymmetric unit contains two crystallographically independent bis-muth metal atoms, one of which lies on an inversion centre and the other on a twofold axis...

Spores of Bacillus subtilis are being used as probiotics and competitive exclusion agents for animal consumption. Commercial production media often include relatively expensive components of animal origin that are a potential source for the presence of adventious agents, therefore undesirable for use in production scale. In this study a new animal-free component, chemically defined medium, was ...

Alpine meadows are one major type of pastureland on the Tibetan Plateau. However, few studies have evaluated the response of soil respiration (R(s)) to grazing along an elevation gradient in an alpine meadow on the Tibetan Plateau. Here three fenced enclosures were established in an alpine meadow at three elevations (i.e., 4313 m, 4513 m, and 4693 m) in July 2008. We measured R s inside and out...

In the in-situ remediation of ammonium (NH4+) in groundwater by a sequential reactive barrier filled with zeolite, it is of great importance to understand the mechanisms of NH4+ sorption to zeolite. In this study, the effect of dissolved natural organic matter on NH4+ sorption to natural Chinese clinoptilolite was studied by batch experiments taking humic acid (HA) as a model substance. The sur...

A selective ultraperformance liquid chromatographic (UPLC) method for the determination of magnesium valproate and its process related impurities has been developed. The method includes reversed-phase Acquity BEH C18 column with 100 mm × 2.1 mm i.d. and 1.7 µ particle size. The mobile phase consists of acetonitrile and 5 mM ammonium dihydrogen orthophosphate with pH = 3.0 at 45 : 55 isocratic e...

Reaction pathway investigations of the solvothermal preparation of nanocrystalline Culn1xGa xSe2 in triethylenetetramine reveal the early formation of a previously unreported CU2-xSe(S) intermediate. Over 24 hours, this reacts with In and Se species to form CulnSe2(s). If Ga is present, the reaction proceeds over an additional 48 hours to form Culn1xGa xSe2. Adding ammonium halide salts reduces...