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Staudinger Reaction (staudinger + reaction)
Selected AbstractsChemInform Abstract: Staudinger Reaction in the Series of 4-Diazotetrahydrofuran-3-ones: Effect of Substituents in the Diazo and Phosphine Components.CHEMINFORM, Issue 24 2008L. L. Rodina Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] 2-Aryl-4-azido-3-(bromo/iodo)quinolines as substrates for the synthesis of primary 4-amino-2,3-disubstituted quinoline derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2008Malose J. Mphahlele Staudinger reaction of the 2-aryl-4-azido-3-bromoquinolines and 2-aryl-4-azido-3-iodoquinolines with triphenyl phosphine in refluxing tetrahydrofuran afforded series of 2-aryl-3-halogeno-4-(triphenylphosphoranylideneamino)quinolines. The latter were, in turn, hydrolyzed to the corresponding primary 4-amino-2-aryl-3-(bromo/iodo)quinolines using 80% acetic acid under reflux. Tetrakis(triphenylphosphine)-palladium(O)-catalyzed Suzuki reaction of the 2-aryl-3-iodo-4-(triphenylphosphoranylideneamino)-quinolines with phenylboronic acid in dimethyl formamide in the presence of 2 M K2CO3 followed by hydrolysis of the incipient 2,3-diaryl-4-(triphenylphosphoranylideneamino)quinolines with 80% acetic acid afforded the 4-amino-2,3-diarylquinolines. [source] Urea bonded cyclodextrin derivatives onto silica for chiral HPLCJOURNAL OF SEPARATION SCIENCE, JSS, Issue 12 2006I. Wayan Muderawan Abstract Several structurally well-defined perfunctionalised cyclodextrin chiral stationary phases (CD CSPs) for high performance liquid chromatography have been successfully prepared by immobilisation of perfunctionalised cyclodextrins on silica through urea linkage(s) using the Staudinger reaction. These CSPs show high chiral recognition efficiency and are utilised in the resolution of various types of racemic compounds. This paper reviews the development of sixteen perfunctionalised cyclodextrin-based CSPs, their preparation, and their application to enantioseparation of seventy-seven racemic compounds under a range of separation conditions. [source] Synthesis and Reactivity of 6,7-dihydrogeranylazides: Reagents for Primary Azide Incorporation into Peptides and Subsequent Staudinger LigationCHEMICAL BIOLOGY & DRUG DESIGN, Issue 2 2006Juhua Xu Protein farnesyltransferase (PFTase) catalyzes the attachment of a geranylazide moiety to a peptide substrate, N -dansyl-GCVIA. Because geranylazide is actually a mixture of isomeric, interconverting primary and secondary azides, incorporation of this isoprenoid into peptides can potentially result in a corresponding mixture of prenylated peptides. Here, we first examined the reactivity of geranyl azide in a model Staudinger reaction and determined that a mixture of products is formed. We then describe the synthesis of 6,7-dihydrogeranylazide diphosphate and demonstrate that this compound allows exclusive incorporation of a primary azide into a peptide. The resulting azide-containing peptide was derivatized with a triphenylphosphine-based reagent to generate an O -alkyl imidate-linked product. Finally, we show, using a series of model reactions, that the Staudinger ligation frequently produces small amounts of O -alkyl imidate products in addition to the major amide-linked products. Thus, the alkoxyimidates we have observed as the exclusive products in the reactions of peptides containing prenylated azides also appear to be a common type of product formed using other azide-containing reactants, although at greatly reduced levels. This method for chemical modification of the C-terminus of a protein should be useful for a variety of applications in protein chemistry. [source] Preparation and enantioseparation characteristics of two chiral stationary phases based on mono(6A -azido-6A -deoxy)-perphenylcarbamoylated ,- and ,-cyclodextrinCHIRALITY, Issue 9 2004Xiang-Hua Lai Abstract Two chiral stationary phases, ph-,-CD and ph-,-CD, were prepared from mono(6A -azido-6A -deoxy)perphenylcarbamoylated ,- and ,-cyclodextrin immobilized onto silica gel via the Staudinger reaction. The chromatographic characteristics of these two chiral stationary phases were evaluated. The influence of different cyclodextrins (CDs) on the enantioselectivities was also investigated in this study. Compared to ph-,-CD, ph-,-CD exhibited quite good enantioselectivity toward the analytes with bulky molecular structures. It was found that the formation of inclusion complex might play a quite important role in the chiral recognition not only under reverse phases but also under normal phases. Chirality 16:592,597, 2004. © 2004 Wiley-Liss, Inc. [source] | ||||||||||