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Published on: June 10, 2021
Total Synthesis of Termicalcicolanone A via Organocatalysis and Regioselective Claisen Rearrangement
Saki Ito1, Taiki Kitamura2, Sundaram Arulmozhiraja3,4
1Department of Materials and Life Sciences, Faculty of Science and Technology , Sophia University , 7-1 Kioicho , Chiyoda-ku, Tokyo 102-8554 , Japan.
Abstract:
A total synthesis of an anticancer xanthone natural product termicalcicolanone A utilizing multiple nucleophilic aromatic substitutions and pericyclic reactions has been developed. The pyrano[3,2- b]xanthen-6-one scaffold was constructed via NHC-catalyzed aroylation to produce the benzophenone intermediate, Claisen cyclization to form the pyran ring, and intramolecular 1,4-addition to construct the xanthone framework. The prenyl group was introduced in the final stages of the synthesis through regioselective Claisen rearrangement. The synthesis has been achieved in 19 steps.
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