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Various Nucleophiles (various + nucleophile)
Selected AbstractsGold(I)-Catalyzed Tandem Rearrangement,Nucleophilic Substitution of ,-Acetoxy Alkynyl Oxiranes or Aziridines: Efficient Approach to Furans and PyrrolesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 9 2010Aurélien Blanc Abstract Highly substituted furans and pyrroles were efficiently formed by a new gold(I)-catalyzed tandem rearrangement,nucleophilic substitution of acetoxylated alkynyl oxiranes and aziridines in the presence of various nucleophiles. [source] An Efficient Synthesis of Novel ,-Aminophosphonates Based on a Mannich-Type ReactionEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2005Nikolaus Risch Abstract Phosphonate-substituted iminium salt 2 was used in Mannich reactions with various nucleophiles to obtain novel ,-aminophosphonates. This straightforward and efficient methodology has a broad scope and provides highly functionalized Mannich bases (4 and 8). Furthermore, vinylic, aromatic and homoallylic ,-aminophosphonates (5, 10 and 12) were synthesized in good yields. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Post-synthesis incorporation of a lipidic side chain into a peptide on solid supportJOURNAL OF PEPTIDE SCIENCE, Issue 11 2002Céline Douat Abstract A new strategy for the synthesis of lipopeptides has been developed. Using Weinreb (N -methoxy, N -methyl) amide as an aldehyde function precursor on the side chains of Asp or Glu residues, this new strategy avoids the synthesis of a lipidic amino acid residue before its incorporation in the peptide sequence. The aldehyde generated on the solid support can react with ylides leading to unsaturated or saturated side chains or with various nucleophiles to yield non-coded amino acid residues incorporated into the sequence. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd. [source] Stereocontrolled Intramolecular Aziridination of Glycals: Ready Access to Aminoglycosides and Mechanistic Insights from DFT StudiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 5 2008Rujee Lorpitthaya Abstract Stereocontrolled intramolecular aziridination of the glycal-derived sulfamates offers a highly efficient strategy to divergently prepare aminoglycosides. Rhodium-catalyzed nitrogen-atom transfer to CC bonds formed semistable aziridines, which were subjected to various nucleophiles (C, O, S, and N) to give cyclic sulfamate-containing aminosugar derivatives selectively. The second nucleophilic displacement of sulfonyloxy moieties of [1,2,3]-oxathiazepane-2,2- dioxides allows straightforward access to aminoglycosides with selective ,- or ,-linkages. This approach is operationally simple, complements existing methods, and is a versatile protocol for the synthesis of polyfunctionalized amino sugars. In addition, the mechanism of the rhodium-catalyzed intramolecular aziridination of glycals and its ring-opening reaction was extensively studied by using DFT calculations. [source] |