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Updated: May 24, 2026
10:12
Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
ent-(15S)-Pimar-8(14)-ene-15,16-diol
Acta Crystallographica. Section E, Structure Reports Online
|February 21, 2012
Summary
A novel ent-pimarane diterpenoid was isolated from Ceriops tagal stem bark. Its crystal structure reveals specific ring conformations and intermolecular hydrogen bonding in the solid state.
Area of Science:
- Natural Products Chemistry
- Organic Chemistry
- Crystallography
Background:
- Ceriops tagal is a mangrove species known for its rich phytochemical constituents.
- Diterpenoids, a class of natural products, exhibit diverse biological activities.
- Understanding the structure of isolated compounds is crucial for further research.
Purpose of the Study:
- To isolate and characterize a novel ent-pimarane diterpenoid from Ceriops tagal.
- To elucidate the crystal structure of the isolated compound.
- To investigate the conformational preferences and intermolecular interactions in the solid state.
Main Methods:
- Isolation of the compound using chromatographic techniques.
- Structure determination via spectroscopic methods (e.g., NMR, MS).
- Single-crystal X-ray diffraction analysis for crystallographic data.
Main Results:
- An ent-pimarane diterpenoid, (S)-1-[(2S,4aR,8aR)-2,4b,8,8-tetra-methyl-2,3,4,4a,4b,5,6,7,8,8a,9,10-dodeca-hydro-phenanthren-2-yl]ethane-1,2-diol, was successfully isolated.
- The crystal structure revealed two conformationally similar independent molecules in the asymmetric unit.
- Specific conformations of the fused ring system (chair for cyclohexane, envelope for cyclohexene) and O-H⋯O hydrogen bonding were observed.
Conclusions:
- The study successfully identified and characterized a new ent-pimarane diterpenoid from Ceriops tagal.
- The crystallographic analysis provides detailed insights into the compound's solid-state structure and molecular packing.
- This structural information can serve as a basis for understanding its potential biological activities.
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