Enantioselective Synthesis of Oasomycin A, Part III: Fragment Assembly and Confirmation of Structure†
David A. Evans Prof.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorPavel Nagorny
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorKenneth J. McRae Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorLouis-Sebastian Sonntag Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorDominic J. Reynolds Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorFilisaty Vounatsos Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorDavid A. Evans Prof.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorPavel Nagorny
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorKenneth J. McRae Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorLouis-Sebastian Sonntag Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorDominic J. Reynolds Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorFilisaty Vounatsos Dr.
Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617–495–1460
Search for more papers by this authorFinancial support has been provided by the National Institutes of Health (GM-33327-19), the Merck Research Laboratories, Amgen, and Eli Lilly. A postdoctoral fellowship was provided to L.-S.S. by the Deutscher Akademischer Austauschdienst and the Novartis Foundation, and to D.J.R. by the Glaxo Foundation.
Graphical Abstract
Putting the pieces together: The total synthesis of the natural macrolide oasomycin A has been realized. Key fragment couplings include an anti-Felkin selective aldol addition (green), Kociensky–Julia olefinations (red), and competitive Weinreb amide acylation reaction (blue). The utility of the 4,5-diphenyloxazole as a carboxy surrogate and the late-stage macrolactonization affording the 42-membered macrocycle of oasomycin A are also described.
Supporting Information
Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z603652_s.pdf or from the author.
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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