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Published on: April 4, 2014
Conversion of Phorbol into Des-D-Ring Tricycle and Crotonianoid B via Peroxidation Reaction
Ayumu Watanabe1, Yuto Hikone1, Masanori Nagatomo1
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
Phorbol (1) has a tetracyclic ABCD-ring and is readily isolable from a natural source. We previously synthesized 1 and 16 structurally related natural products using common ABC-ring intermediate 2. Here we report a new synthetic route to 2 using 1 as a starting material. Key features of the synthesis are chemoselective removal of the D-ring via cyclopropane opening, peroxidation, and retro-aldol reactions. The high utility of the peroxidation was further demonstrated in the first synthesis of crotonianoid B (9).
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