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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Bicunningines A and B, two new dimeric diterpenes from Cunninghamia lanceolata
Xian-Feng Hou1, Sheng Yao, Attila Mándi
1State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China.
Organic Letters
|December 29, 2011
Summary
Two new dimeric diterpenoids were discovered in Cunninghamia lanceolata. Their structures were confirmed using advanced spectroscopic and computational methods, with MPA esterification proving reliable for determining absolute configuration.
Area of Science:
- Natural Product Chemistry
- Organic Chemistry
- Phytochemistry
Background:
- Cunninghamia lanceolata is a valuable timber species with potential for novel bioactive compound discovery.
- Dimeric diterpenoids represent a complex class of natural products with diverse chemical scaffolds.
- Understanding the structural diversity of diterpenoids aids in exploring their biological activities.
Purpose of the Study:
- To isolate and characterize unprecedented dimeric diterpenoids from Cunninghamia lanceolata.
- To elucidate the detailed structures and absolute configurations of these novel compounds.
- To evaluate the reliability of different methods for determining absolute configuration in sterically hindered systems.
Main Methods:
- Isolation of compounds using chromatographic techniques.
- Structure elucidation via comprehensive spectroscopic measurements (NMR, MS, etc.).
- Determination of absolute configuration using quantum chemical TDDFT ECD calculations, chemical transformations, and Mosher's method (MPA and MTPA esterification).
Main Results:
- Isolation of two novel dimeric diterpenoids featuring a unique 2,3-dihydrofuran ring system.
- Successful elucidation of their structures, revealing a fusion of abietane and 4,5-seco-abietane diterpene units.
- Identification of discrepancies in Mosher's method for the sterically hindered sec-hydroxyl group, with MPA esterification yielding the correct absolute configuration.
Conclusions:
- Cunninghamia lanceolata harbors unique dimeric diterpenoids with complex fused ring systems.
- The study highlights the importance of employing multiple complementary methods for accurate structure determination.
- MPA esterification is confirmed as a reliable method for establishing the absolute configuration of sterically hindered sec-hydroxyl groups in diterpenoids.
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