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Search for "rearrangements" in Full Text gives 181 result(s) in Beilstein Journal of Organic Chemistry.

Radical cascades using enantioenriched 7-azabenzonorbornenes and their applications in synthesis

  • David M. Hodgson and
  • Leonard H. Winning

Beilstein J. Org. Chem. 2008, 4, No. 38, doi:10.3762/bjoc.4.38

Graphical Abstract
  • -azabenzonorbornadienes. Oxidation (using RuO4) and Birch reduction of the 2-aza-5,6-benzonorbornenes provide access to substituted pyrrolidines and tetrahydroindenes, respectively. Keywords: asymmetric synthesis; deoxygenation; radicals; rearrangements; tandem reactions; Introduction Carbon-centred radicals have been
  • is most conveniently achieved by the incorporation of one or more structural directing effect(s). Research in our laboratory has focussed on using the potential dative stabilising effect of an α-nitrogen in the product-producing radical to direct homoallylic radical rearrangements for use in azacycle
  • synthesis [14]. The utility of nitrogen-directed radical rearrangements in the 7-azanorbornene system has been reported previously in relation to the synthesis of a variety of biologically-relevant targets, including epibatidine analogues [15][16], kainic acid [17][18] and ibogamine [19]. In these studies
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Published 24 Oct 2008

Desymmetrization of 7-azabicycloalkenes by tandem olefin metathesis for the preparation of natural product scaffolds

  • Wolfgang Maison,
  • Marina Büchert and
  • Nina Deppermann

Beilstein J. Org. Chem. 2007, 3, No. 48, doi:10.1186/1860-5397-3-48

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  • , ring closing metathesis (RCM) and tandem metatheses [10][11][12][13] have been particularly successful strategies for the assembly of common natural product scaffolds. [14][15][16][17][18][19][20][21][22] A general advantage of these approaches is that ring closure and/or scaffold-rearrangements can be
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Published 18 Dec 2007

Investigation of acetyl migrations in furanosides

  • O. P. Chevallier and
  • M. E. Migaud

Beilstein J. Org. Chem. 2006, 2, No. 14, doi:10.1186/1860-5397-2-14

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  • degradation under such conditions of the synthetic intermediates of compounds 1–5, all incorporating either an acetonide or a methyl ketal moiety. The reactions were stopped as soon as complete disappearance of the starting material had occurred to minimise rearrangements subsequent to the deprotection step
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Published 21 Jul 2006

Colchitaxel, a coupled compound made from microtubule inhibitors colchicine and paclitaxel

  • Karunananda Bombuwala,
  • Thomas Kinstle,
  • Vladimir Popik,
  • Sonal O. Uppal,
  • James B. Olesen,
  • Jose Viña and
  • Carol A. Heckman

Beilstein J. Org. Chem. 2006, 2, No. 13, doi:10.1186/1860-5397-2-13

Graphical Abstract
  • microtubule array. It decreases the tendency of microtubules to be anchored in the microtubule organizing center [57] and causes rearrangement into patterns that are rarely found in untreated cells. Such rearrangements included parallel arrays at the cell edge and focal points in the cytoplasm from which
  • , the coupled agent retained some of the effects of the combination of starting agents but had fewer effects on microtubule structure. Future investigation of colchitaxel-treated cells by the shape assay will be useful in determining whether the microtubule rearrangements coincide with the reversal of
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Published 30 Jun 2006

Total syntheses of oxygenated brazanquinones via regioselective homologous anionic Fries rearrangement of benzylic O-carbamates

  • Glaucia Barbosa Candido Alves Slana,
  • Mariângela Soares de Azevedo,
  • Rosângela Sabattini Capella Lopes,
  • Cláudio Cerqueira Lopes and
  • Jari Nobrega Cardoso

Beilstein J. Org. Chem. 2006, 2, No. 1, doi:10.1186/1860-5397-2-1

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  • construction of these bioactive compounds for future biological evaluation. The emerging carbanionic aromatic chemistry (anionic ortho-Fries, [13] homologous anionic Fries, [14] remote anionic Fries rearrangements [15] and carbamoyl Baker-Venkataraman reaction [16]) originating from the Directed ortho
  • metalation groups (DMGs) undergo competitive anionic [1,2] and [1,4] Wittig – carbamoyl rearrangements (paths a and b) [18][19] orientated by the groups R and DMGs (Figure 1). Conceptual combination of path b and the well established tandem DoM route to anthraquinones and heteroanthraquinones [20] led to the
  • described. This methodology could be expanded in the future for the construction of new molecules with similar structures. Examples of carbanionic aromatic chemistry rearrangements. Retrosyntheses of Brazanquinones (1). Total syntheses of brazanquinones (1 a-c). Total syntheses of phthalide (9). Supporting
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Published 21 Feb 2006

Stereoselective α-fluoroamide and α-fluoro- γ-lactone synthesis by an asymmetric zwitterionic aza-Claisen rearrangement

  • Kenny Tenza,
  • Julian S. Northen,
  • David O'Hagan and
  • Alexandra M. Z. Slawin

Beilstein J. Org. Chem. 2005, 1, No. 13, doi:10.1186/1860-5397-1-13

Graphical Abstract
  • fluorinated substrates, to generate α-fluoro-γ-vinyl amides and then α-fluoro-γ-lactones as the end products after iodolactonisation. In 1998 Nubbemeyer[12][13] reported on such aza-Claisen rearrangements using the N-allylproline ester 1 and the N-allylpyrrolidine ether 2 with the acid fluoride of azidoacetic
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Published 17 Oct 2005
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