Stereoselective Synthesis of (±)-Cephanolide B
Anding Li1, Ziru He1, Bingyan Liu1
1State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
Abstract:
A concise and stereoselective total synthesis of (±)-cephanolide B was achieved in 15 steps. The key steps in the synthesis were as follows: (i) an intermolecular Diels-Alder reaction followed by lactonization to form the oxabicyclo[2.2.2]octane DE ring; (ii) a tandem reaction, featuring an intramolecular Pauson-Khand reaction, a 6π-electrocyclization, and an oxidative aromatization by O2, to construct the ABC-tricyclic rings (6-5-6); and (iii) a phthaloyl peroxide-mediated arene oxygenation to install the C-13 phenol group.
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