Synlett 1994; 1994(8): 591-593
DOI: 10.1055/s-1994-22937
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Synthesis of the C20-C34 Segment of the Immunosuppressant FK-506 via Stereocontrolled Aldol Coupling. Application of a Remote Chelation Effect

James D. White* , Steven G. Toske, Takayuki Yakura
  • *Department of Chemistry, Oregon State University, Corvallis, Oregon, USA 97331-4003
Further Information

Publication History

Publication Date:
18 September 2002 (online)

Stereoselective aldol condensation of an α-chiral methyl ketone, prepared from ethyl (R)-3-hydroxybutyrate, with an α-chiral aldehyde, prepared from (-)-quinic acid, was used to construct the C20-C34 segment of the immunosuppressant FK-506. Stereoselection in this process is attributed to tight coordination of the lithium enolate with a β-trityl ether thereby imparting a large steric bias to the ketone enolate.

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