posted on 2003-04-09, 00:00authored byKhee Dong Eom, J. Venkat Raman, Heejin Kim, Jin Kun Cha
A convergent synthesis of (+)-asteltoxin (1) has been achieved by the Horner−Emmons
olefination of bis(tetrahydrofuran) aldehyde 53 and α-pyrone phosphonate 5. A key step features the
stereoselective construction of a sterically congested quaternary center embedded in the densely
functionalized bis(tetrahydrofuran) subunit by a Lewis acid-catalyzed, pinacol-type rearrangement of an
epoxy silyl ether. This pivotal rearrangement methodology parallels the proposed biosynthetic pathway of
1 and is ripe for applications to the stereocontrolled synthesis of structurally complex natural products.