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Updated: Jun 20, 2026

Optimization of the Ugi Reaction Using Parallel Synthesis and Automated Liquid Handling
Published on: November 11, 2008
Scalable Protecting-Group-Free Total Synthesis of Resibufogenin and Bufalin
Shaopeng Yu1, Qiuheng Zhang1, Xueqing Zhong1
1The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
Abstract:
A chemoenzymatic synthesis access to resibufogenin and bufalin was developed in seven steps without protecting groups. Starting with androstenedione (AD), an α-OH was introduced directly at C14 by hydroxylase P-450lun, which was further used as the directing group for hydrogenation to fully control the C17 configuration in the β-orientation after Suzuki cross-coupling. Dehydration of 14α-OH followed by an epoxidation delivered resibufogenin. Simultaneously, bufalin was also obtained via a challenging anaerobic Mukaiyama hydration.
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