ORGN 149 |
Total synthesis of furaquinocin A, B and E
| Oliver R. Thiel1, Barry M. Trost2, and Hon Chung Tsui2. (1) Small Molecules Process Research, Amgen, One Amgen Center Drive, Thousand Oaks, CA 91320, (2) Department of Chemistry, Stanford University, Stanford, CA 94305 |
| A modular approach culminated in the total syntheses of furaquinocin A, B and E. A Pd-catalyzed dynamic kinetic asymmetric transformation (DYKAT) on carbonates derived from Baylis-Hillman adducts, followed by a reductive Heck-cyclization allows the enantio- and diastereoselective construction of the dihydrobenzofuran core. Introduction of a double unsatured side chain via Horner-Wadsworth-Emmons reaction and assembly of the naphthoquinone with squaric acid based methodology leads to furaquinocin E. The use of differentially substituted squaric acid derivatives allows the synthesis of three analogues of furaquinocin E. The additional stereocenters in furaquinocin A and B can be introduced with a diastereoselective Sakurai allylation. The stereoselective elongation of the side chain is possible using cross metathesis or ring closing metathesis. The obtained late stage intermediates were successfully transformed to furaquinocin A and B. 
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Asymmetric Reactions and Syntheses, Metal-Mediated Reactions, Materials, Molecular Recognition
8:00 PM-10:00 PM, Sunday, August 22, 2004 Pennsylvania Convention Center -- Hall D, Poster
Sci-Mix
8:00 PM-10:00 PM, Monday, August 23, 2004 Pennsylvania Convention Center -- Hall D, Sci-Mix
Division of Organic Chemistry
The 228th ACS National Meeting, in Philadelphia, PA, August 22-26, 2004
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