Chemoenzymatic route to both enantiomers of a 1-isopropyl-3a- methyloctahydroinden-4-one derivative: A synthetic intermediate for sesqui- and diterpenoids

Shigeo Fujieda, Mina Tomita, Ken Ichi Fuhshuku, Shigeru Ohba, Shigeru Nishiyama, Takeshi Sugai

研究成果: Article査読

14 被引用数 (Scopus)

抄録

On the way to a chemoenzymatic synthesis of a key intermediate for sesquiterpenoids and diterpenoids, 2-methyl-2-(4-methyl-3-oxopentyl)-1,3- cyclohexanedione was reduced with the whole cells of yeast biocatalysts. Torulaspora delbrueckii NBRC10921 reduced a cyclic ketone of three carbonyl groups in an enantiofacially selective manner (reface attack), but there was poor enantiotopic group selectivity between two carbonyl groups on the cyclohexane ring to yield a mixture of diastereomeric products. Candida floricola IAM13115 reduced mainly the pro-(R) carbonyl group. In contrast, the reduction proceeded in an enantiofacially poorly selective manner to give another set of diastereomeric products. In both cases, another carbonyl group on the side chain worked as a 'trapping arm' of the resulting secondary alcohol. The diastereomeric products were effectively separated as the 'syn' or 'cis' isomer exclusively exist in the intramolecular hemiacetal structure, while 'anti' or 'trans' isomer being an equilibrated mixture of cyclic hemiacetal and open-chain hydroxyketone (ca. 0.7:1). Starting separately from the enantiomerically enriched products as above, both enantiomers of the target compound, a key intermediate for terpenoids, were efficiently prepared via stereoselective ring closure under pinacol coupling reaction conditions. Furthermore, a daucane sesquiterpene intermediate, a hydroazulene derivative, was provided after one-carbon homologation of the six-membered ring.

本文言語English
ページ(範囲)1099-1109
ページ数11
ジャーナルAdvanced Synthesis and Catalysis
347
7-8
DOI
出版ステータスPublished - 2005 6 1

ASJC Scopus subject areas

  • 触媒
  • 有機化学

フィンガープリント

「Chemoenzymatic route to both enantiomers of a 1-isopropyl-3a- methyloctahydroinden-4-one derivative: A synthetic intermediate for sesqui- and diterpenoids」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル