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Published on: May 26, 2019
Total Synthesis of Mulberry Diels-Alder-Type Adducts Kuwanons G and H
Si-Yuan Luo1, Zhuo-Ya Tang1, Qingjiang Li1
1School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, People's Republic of China.
Abstract:
Mulberry Diels-Alder-type adducts (MDAAs) are a group of rare natural polyphenols biosynthetically derived from [4 + 2]-cycloaddition of chalcones and dehydroprenylphenols. In this study, kuwanons G (1) and H (2), two bioactive MDAAs with unique dehydroprenylflavonoid dienes, were totally synthesized for the first time in a biomimetic manner. The key features of the convergent route include the use of the Baker-Venkataraman rearrangement, alkylation of β-diketone, intramolecular cyclization, and Suzuki-Miyaura coupling to achieve the subunit diene.
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