Systematic Asymmetric Synthesis of All Diastereomers of (-)-Talaumidin and Their Neurotrophic Activity

J Org Chem. 2015 Jul 17;80(14):7076-88. doi: 10.1021/acs.joc.5b00945. Epub 2015 Jul 6.

Abstract

(-)-Talaumidin (1), a 2,5-biaryl-3,4-dimethyltetrahydrofuran lignan isolated from Aristolochia arcuata Masters, shows significant neurite-outgrowth promotion and neuroprotection in primary cultured rat cortical neurons and in NGF-differentiated PC12 cells. The four stereogenic centers on the tetrahydrofuran moiety in 1 result in the presence of seven diastereomers except for their enantiomers. In order to investigate the stereochemistry-activity relationships of the stereoisomers, the systematic synthesis of all stereoisomers of 1 was accomplished by employing Evans aldol, diastereoselective hydroboration, reductive deoxygenation, and Mitsunobu reactions as key steps. The ability of all of the synthesized stereoisomers to promote neurite-outgrowth in PC12 and neuronal cells was evaluated. All stereoisomers exhibited moderate to potent neurotrophic activities in NGF-differentiated PC12 cells at 30 μM and in primary cultured rat cortical neuronal cells at 0.01 μM. In particular, 1e bearing all cis substituents resulted in the most potent neurite-outgrowth promotion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aristolochia / chemistry*
  • Cell Differentiation
  • Cell Line
  • Furans / chemical synthesis*
  • Furans / chemistry
  • Furans / isolation & purification
  • Lignans / chemistry*
  • Nerve Growth Factors / chemistry*
  • Neurons / chemistry*
  • PC12 Cells / chemistry*
  • PC12 Cells / drug effects
  • Rats
  • Stereoisomerism

Substances

  • Furans
  • Lignans
  • Nerve Growth Factors
  • talaumidin
  • tetrahydrofuran