99(P-32) 光学活性インゲノールの合成(ポスター発表の部)

• 渡邉 和志

  筑波大数理物質

• 鈴木 佑人

  筑波大数理物質

• 青木 健太

  筑波大数理物質

• 坂倉 彰

  筑波大数理物質

• 末永 聖武

  筑波大数理物質

• 木越 英夫

  筑波大数理物質

書誌事項

タイトル別名

• 99(P-32) Formal Synthesis of Optically Active Ingenol

抄録

Ingenol is a diterpenoid isolated from Euphorbia ingens, possessing a bicyclo[4.4.1]undecane skeleton with a highly strained inside, outside-intrabridgehead stereochemistry. Several strategies for construction of the unique skeleton have been reported, however, direct cyclization to the inside, ousidet-bicyclo[4.4.1]undecane system has not been reported. Recently, two total syntheses in a racemic form using the aforementioned strategies were reported by Winkler and Tanino-Kuwajima. We would like to report the construction of strained carbon skeletons of ingenol by direct cyclization with ring-closing olefin metathesis (RCM). With well-designed diene compounds 4, 23, and 24, RCM was found to be applicable to the formation of a highly strained skeleton of ingenol, and formal total synthesis of optically active ingenol (1) was achieved. The key features of this synthesis are construction of an A-ring by spirocyclization of ketone 21 with an allylic chloride unit and ring closure of a B-ring by olefin metathesis. Starting from Funk's keto ester 17, the key intermediate aldehyde 27 in Winkler's total synthesis was synthesized in eight steps in 12.5% overall yield. This strategy of direct cyclization of a strained inside-outside skeleton provided the first easy access to optically active ingenol.

収録刊行物

• 天然有機化合物討論会講演要旨集

  天然有機化合物討論会講演要旨集 46 (0), 569-574, 2004

  天然有機化合物討論会実行委員会

詳細情報

• CRID: 1390282681054979584
• NII論文ID: 110006682480
• DOI: 10.24496/tennenyuki.46.0_569
• ISSN: 24331856
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可