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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Catalytic Asymmetric Total Synthesis of Roridin E
Seungbin Park1, Geetanjali B Gone1, Jisu Do1
1Department of Biopharmaceutical Convergence, Sungkyunkwan University, Suwon, Gyeonggi16419, Republic of Korea.
Abstract:
We report the first catalytic asymmetric total synthesis of roridin E, a macrocyclic type D trichothecene. Phase-transfer-catalyzed alkylation of a β-keto ester made in one step from an inexpensive enone delivers the first stereodefined (-)-verrucarol precursor in quantitative yield and >99% ee on a decagram scale, and a Z-selective intramolecular Horner-Wadsworth-Emmons macrocyclization completes the route in 33 steps (longest linear sequence). Synthetic roridin E matched the natural isolate in cytotoxicity across six cancer cell lines.
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