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![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Integral stereocontrolled synthesis of a spiro-norlignan, sequosempervirin A: revision of absolute configuration
Yuji Ito1, Kazunori Takahashi, Hiromasa Nagase
1Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41, Shinagawa-ku, Tokyo 142-8501, Japan.
Abstract:
A novel synthetic path to sequosempervirin A was established by employing a samarium diiodide promoted intramolecular Barbier-type reaction of the lactonic iodide, in which the key structural feature, a spiro[4.5]decane ring system, could be constructed by controlling the stereochemistry of the hydroxyl group at the 8-position. The absolute configuration of natural sequosempervirin A was revised to be 4S based on this synthesis.
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