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Water-soluble Analogue (water-soluble + analogue)
Selected AbstractsA Property-Matched Water-Soluble Analogue of the Benchmark Ligand PPh3CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 7 2008Michel Ferreira Abstract A series of sulfonated biphenylphosphanes were readily prepared from commercially available, inexpensive, and air-stable organic compounds. Of these, the trisulfonated trisbiphenylphosphane can be considered as a true water-soluble analogue of PPh3 as the cone angle and basicity of both phosphanes are very close and result in a similar coordination mode on palladium and rhodium complexes. The catalytic performance of the trisulfonated trisbiphenylphosphane was evaluated in the aqueous hydroformylation of 1-decene and the Tsuji,Trost reaction. [source] Antioxidant Activity of Degradable Polymer Poly(trolox ester) to Suppress Oxidative Stress Injury in the CellsADVANCED FUNCTIONAL MATERIALS, Issue 1 2010Paritosh P. Wattamwar Abstract Oxidative stress is a pathological condition that has been implicated as a central player in a variety of diseases, including vascular and neurodegenerative diseases. More recently, oxidative stress has also been shown to be involved in the biological incompatibility of many materials, especially at the nanoscale. As such, there is a critical need for new biomaterials that can inhibit this response, improving the compatibility of medical devices. In this work, trolox, a synthetic antioxidant and water-soluble analogue of Vitamin E, is polymerized to form an oxidation active polymer as a new class of biomaterial. Synthesized poly(trolox ester) polymers were formulated into nanoparticles using a single emulsion technique, and their size was controlled by changing the polymer concentration in the organic solvent. Nanoparticle cytotoxicity, protective effects against cellular oxidative stress, and degradation kinetics were all evaluated. Poly(trolox ester) nanoparticles were found to have little to no cytotoxicity and were capable of suppressing cellular oxidative stress induced by cobalt nanoparticles. In vitro degradation studies of poly(trolox ester) nanoparticles indicate that the antioxidant activity of nanoparticles was derived from its enzymatic degradation to release active antioxidants. [source] Modeling l-dopa purification by chiral ligand-exchange chromatographyAICHE JOURNAL, Issue 3 2007Nooshafarin Sanaie Abstract A model describing elution-band profiles that combines multiple chemical equilibria theory with the nonideal equilibrium,dispersion equation for solute transport is used to predict and characterize the separation of l,d-dopa by chiral ligand-exchange chromatography (CLEC). Formation constants and stoichiometries for all equilibrium complexes formed in the interstitial volume and pore liquid are taken from standard thermodynamic databases and independent potentiometric titration experiments. Formation constants for complexes formed with the stationary phase ligand (N-octyl-3-octylthio-d-valine) are determined from potentiometric titration data for a water-soluble analogue of the ligand. This set of pure thermodynamic parameters is used to calculate the spatially discretized composition of each column volume element as a function of time. The model includes a temperature-dependent pure-component parameter, determined by regression to a single elution band for the pure component, that corrects for subtle effects associated with immobilizing the N-octyl-3-octylthio-d-valine ligand onto the stationary phase. The model is shown to accurately predict elution chromatograms and separation performance as a function of key column operating variables. The model is then used to better understand the connection between chemical equilibria within the system and changes in band profiles and band separation resulting from changes in column operating conditions. © 2007 American Institute of Chemical Engineers AIChE J, 2007 [source] A Property-Matched Water-Soluble Analogue of the Benchmark Ligand PPh3CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 7 2008Michel Ferreira Abstract A series of sulfonated biphenylphosphanes were readily prepared from commercially available, inexpensive, and air-stable organic compounds. Of these, the trisulfonated trisbiphenylphosphane can be considered as a true water-soluble analogue of PPh3 as the cone angle and basicity of both phosphanes are very close and result in a similar coordination mode on palladium and rhodium complexes. The catalytic performance of the trisulfonated trisbiphenylphosphane was evaluated in the aqueous hydroformylation of 1-decene and the Tsuji,Trost reaction. [source] The New Metabolite (S)-Cinnamoylphosphoramide from Streptomyces sp. and Its Total SynthesisEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 30 2008Melanie Quitschau Abstract The tunicate-associated strain Streptomyces sp. JP90 produces the unprecedented metabolite cinnamoylphosphoramide (1) among several other compounds. Structure elucidation was accomplished by NMR spectroscopic studies and efficient total synthesis. The absolute configuration at phosphorus was determined by synthesis of both enantiomers of 1 performing a resolution of the corresponding diastereomeric phosphoramides of L -phenylalanine ethyl ester. Unusual cinnamic acid derivative 1 represents the first bacterial organophosphoramide. As it matches the Schrader's formula for insecticidal organophosphates, its biological activity was investigated. A weak inhibition of acetylcholinesterase was observed in in vitro tests, and water-soluble analogues of 1 were prepared. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] | ||||||||||