Beitrag zum Nachweis von E 605 in biologischem Material

Microchimica Acta - Es wird die Forderung erhoben, den chemischen Nachweis von E 605 in biologischem Material auf den positiven Ausfall sämtlicher drei Komponenten von E 605 (p-Nitrophenol,...     

In vitro nitrosation of ephedrine in the presence of cyclodextrins

-, and -cyclodextrin and heptakis-2,6-di-O-methyl--cyclodextrin enhance the nitrosation rate of l-ephedrine if the nitrosation assay procedure (NAP test) is applied. During this reaction with -cyclodextrin a solid inclusion compound of -cyclodextrin andN-nitrosoephedrine precipitates. Solubilities and stabilities of inclusion compounds of the cyclodextrins with ephedrine and nitrosoephedrine, respectively, explain especially the catalytic effects of some cyclodextrins on ephedrine.Part of the PhD thesis of V. Wedelich, Freie Universität Berlin, 1985.     

Stereospecific Synthesis of (E,E)-9, 11, 13-Tetradecatrienyl Acetate and Aldehyde (Geometrical Isoers of the Major Components of Two Sex Pheromones of Lepidoptera)

A stereospecific synthesis of (E,E)-9, 11, 13-tetradecatrienyl acetate and aldehyde is described. The key steps are two sequential palladium-catalyzed cross-coupling reactions between adequate organometalic reagents and the (E)-1,2-dibromoethylene.     

Polymer microfluidic chips for electrochemical and biochemical analyses

Our recent developments concerning the fabrication of polymer microchips and their applications for biochemical analyses are reviewed. We first describe two methods of fabrication of polymer microfluidic chips, namely UV-laser photoablation and plasma etching that are well suited for the prototyping and mass fabrication of microchannel networks with integrated microelectrodes. These microanalytical systems can be coupled with various detection means including mass spectrometry, and their applications in capillary electrophoresis are presented here. We also present how UV laser photoablation can be used for the patterning of biomolecules on polymer surfaces for generating two-dimensional arrays of microspots to carry out affinity assays. Finally, the use of the microchips for the development of fast affinity and immunological assays with electrochemical detection is presented, demonstrating the potential of these polymer microchips for medical diagnostics and drug discovery.     

A Global Existence Result for the Compressible Navier–Stokes Equations in the Critical L p Framework

The present paper is dedicated to the global well-posedness issue for the barotropic compressible Navier–Stokes system in the whole space mathbbR^d{mathbb{R}^d} with d ≧ 2. We aim at extending the work by Danchin (Inventiones Mathematicae 141(3):579–614, 2000) to a critical framework which is not related to the energy space. For small perturbations of a stable equilibrium state in the sense of suitable L ^p -type Besov norms, we establish the global existence. As a consequence, like for incompressible flows, one may exhibit a class of large highly oscillating initial velocity fields for which global existence and uniqueness holds true. In passing, we obtain new estimates for the linearized and the paralinearized systems which may be of interest for future works on compressible flows.     

Preparation,X-ray crystallography,and thermolysis of phenylenediammonium dibromide salts

Phenylenediammonium dibromide (PDADBr) salts have been prepared and characterized by X-ray crystallography. The thermal decomposition of PDADBr has been studied by thermogravimetry (TG) and differential thermal analysis (DTA). Kinetic parameters have been evaluated using model fitting and isoconversional methods. The thermolytic pathways have also been suggested which involve proton transfer as a primary step to regenerate parent amine and HBr. Interaction between amine and HBr at higher temperature yields gaseous products.     

Expeditious synthesis of TADDOL-derived phosphoramidite and phosphonite ligands

A simple and reliable protocol for the synthesis of TADDOL-derived monodentate ligands is reported. The reaction of the requisite TADDOL with PCl₃ is immediately followed by the treatment of the crude intermediate with both nitrogen and carbon nucleophiles. Several previously unknown or difficult-to-make phosphoramidite and phosphonite ligands L1–L3 and L4–L9 were accessed using this novel procedure.