Stereochemical investigations of the Tetrahymena cyclase, a model system for euphane/tirucallane biosynthesis.

@article{Giner2017StereochemicalIO,
  title={Stereochemical investigations of the Tetrahymena cyclase, a model system for euphane/tirucallane biosynthesis.},
  author={Jos{\'e}-Luis Giner and Ju Feng},
  journal={Organic \& biomolecular chemistry},
  year={2017},
  volume={15 13},
  pages={
          2823-2830
        }
}
  • J. Giner, Ju Feng
  • Published 28 March 2017
  • Chemistry, Biology
  • Organic & biomolecular chemistry
The squalene cyclase of Tetrahymena pyriformis cyclizes 2,3-dihydrosqualene to euph-7-ene. This was used as a model for euphane biosynthesis. D-ring formation was demonstrated to involve pre-chair folding through an experiment with 2,3-dihydro-5-oxasqualene. This requires that a non-least motion rotation (120°) of the C17-20 bond in the intermediate deoxydammaranyl cation occurs before the first 1,2-hydride shift. Truncated substrates relieved the hindrance associated with this rotation and… 
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Citation Type

Further terpenoids from Euphorbia tirucalli.
Biosynthesis of Triterpenoid Natural Products
Synthetic studies towards the mannolides: Construction of the bowl-shaped B/C/D ring system
Batatasenol, a Major Triterpenol from Sweet Potato Skins
  • J. Giner
  • Medicine, Chemistry
    Chemistry & biodiversity
  • 2019
TLDR
It is proposed that their biosynthesis involves an epoxysqualene cyclase which can carry out both all‐chair and B‐boat cyclizations.
Deciphering the evolutionary history of microbial cyclic triterpenoids.

References

SHOWING 1-10 OF 17 REFERENCES
Stereospecific synthesis of squalenoid epoxide vinyl ethers as inhibitors of 2,3-oxidosqualene cyclase
The stereospecific synthesis of squalenoid epoxide vinyl ethers with an isopentyloxy group is described. The synthesis involves the preparation of the C22 squalenoid aldehyde bromohydrin (15) by a…
Enyzmatic cyclization of 2,3-dihydrosqualene into euph-7-ene by a cell-free system from the protozoon Tetrahymena pyriformis
The cyclase of the protozoon Tetrahymena pyriformis, which normally converts squalene into the pentacyclic tetrahymanol, cyclized 2,3-dihydrosqualene into euph-7-ene with an unexpected tetracyclic…
Zur Kenntnis der Triterpene. 190. Mitteilung. Eine stereochemische Interpretation der biogenetischen Isoprenregel bei den Triterpenen
The biogenetic isoprene rule in its application to the triterpenes is discussed from a stereochemical standpoint. On the basis of a well defined system of arbitrary assumptions a scheme has been…
Structure and reactivity of the dammarenyl cation: configurational transmission in triterpene synthesis.
TLDR
The structure and reactivity of 13 were studied to understand the factors governing the regio- and stereospecificity of triterpene synthesis, and the rule of configurational transmission aided in elucidating the mechanistic pathway accessed by individual cyclases.
Zur Kenntnis der Triterpene. 183. Mitteilung. Über die Konstitution und Konfiguration von Tirucallol, Euphorbol und Elemadienolsäure
1. By degradation of the tetracyclic alcohol tirucallol (V) into the tricyclic compound XI and methyl L-(+)-2,6-dimethyl-oenanthate (X) it has been shown that tirucallol differs from the isomeric…
Fern constituents: Polypodatetraenes, novel bicyclic triterpenoids, isolated from polypodiaceous and aspidiaceous plants
Synthesis of squalene epoxide and lanosterol analogues for a biosynthetic experiment
Stereospecific enzymic cyclization of a synthetic 2,3-oxidosqualene analogue bearing an 18Z carbon-carbon double bond
NMR Spectra of Triterpenoids. I. Conformation of the Side Chain of Hopane and Isohopane, and Their Derivatives
The 1H- and 13C-NMR signals of eight triterpenoids belonging to the hopane and isohopane groups were completely assigned, and the conformations of their side chains are discussed on the basis of…
Zur Kenntnis der Triterpene. 182. Mitteilung. Konstitution und Konfiguration von Euphol und iso‐Euphenol
It is shown that the isomeric alcohols euphol and lanosterol differ only in the configuration of carbon atoms 13, 14 and 17. In all further structural and steric details the two alcohols are…
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