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Updated: Jul 5, 2026

Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
Total synthesis of (+)-phorboxazole A exploiting the Petasis-Ferrier rearrangement
A B Smith1, K P Minbiole, P R Verhoest
1Department of Chemistry, Monell Chemical Senses Center, University of Pennsylvania, Philadelphia, PA 19104, USA.
Abstract:
A highly convergent, stereocontrolled total synthesis of the potent antiproliferative agent (+)-phorboxazole A (1) has been achieved. Highlights of the synthesis include: modified Petasis-Ferrier rearrangements for assembly of both the C(11-15) and C(22-26) cis-tetrahydropyran rings; extension of the Julia olefination to the synthesis of enol ethers; the design, synthesis, and application of a novel bifunctional oxazole linchpin; and Stille coupling of a C(28) trimethyl stannane with a C(29) oxazole triflate. The longest linear sequence leading to (+)-phorboxazole A (1) was 27 steps, with an overall yield of 3%.
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