Polyene Cyclization/Mannich Cascade for Streamlined Construction of the A/E/F Tricyclic System of Diterpenoid
Yueshen Feng1, Shuping Li1, Minhang Chang1
1Shaanxi Key Laboratory of Natural Products and Chemical Biology, College of Chemistry and Pharmacy, Northwest A&F University, 3 Taicheng Road, Yangling, Shaanxi Province 712100, China.
Abstract:
The A/E/F tricyclic system characteristic of C18-, C19-, and denudatine-type C20-diterpenoid alkaloids was constructed via a strategically designed polyene cyclization/Mannich cascade. The configurational inversion of the phenyl group at C7 successfully proceeded through a radical cascade process involving sequential 1,5-HAT and intermolecular HAT, ultimately establishing the desired tricyclic system with an β-oriented phenyl group.
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