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Astracondensatol D: A 6/6/5/6 Cycloartane Triterpenoid from Astragalus condensatus

Fadime Aydoğan1,2, Pankaj Pandey1, Frank R Fronczek3

  • 1National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, Mississippi 38677, United States.

Organic Letters
|March 12, 2025
PubMed

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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
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