Reductive Aldol Approach to Natural Products: Bioinspired Synthesis of abeo-11(12 → 13)-Oleanane Triterpenoids
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Updated: Jul 19, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
1Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, No. 429, Zhangheng Road, Shanghai 200213, P. R. China.
Abstract:
A synthesis of alstoscholarinoid B (1) and 3β-acetoxy-11α-hydroxy-11(12 → 13)abeooleanan-12-al (2) has been accomplished in 7-9 steps and 10%-16% overall yield from oleanolic acid. This synthesis featured a bioinspired SmI2-mediated reductive aldol reaction to establish the abeo-11(12 → 13)-oleanane framework of both 1 and 2 and a retro-aldol/aldol/lactonization cascade to fully construct the skeleton of 1. Moreover, the investigation of the bioinspired aldol reaction also sheds light on the potential biogenesis of natural products.
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