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Updated: Apr 22, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
A seco-catechin cyclization approach to 4→6-linked catechin dimers
Gen Watanabe1, Ken Ohmori, Keisuke Suzuki
1Department of Chemistry, Tokyo Institute of Technology, O-okayama, Meguro, Tokyo 152-8551, Japan. kohmori@chem.titech.ac.jp ksuzuki@chem.titech.ac.jp.
Abstract:
A viable route has been developed for the selective synthesis of the 4→6-linked catechin dimers, scarcely accessible from Nature and/or through synthesis. An acyclic nucleophilic catechin precursor (seco-catechin) was used for the regioselective union with an electrophilic catechin unit, and subsequent pyran cyclization gave the desired 4→6-linked dimers, i.e., procyanidin B6 and catechin-(4α→6)-gallocatechin.
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