Synlett 2017; 28(18): 2505-2508
DOI: 10.1055/s-0036-1588529
letter
© Georg Thieme Verlag Stuttgart · New York

Nonenzymatic Biomimetic Synthesis of Black Tea Pigment Theaflavins

Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan   eMail: y-matsuo@nagasaki-u.ac.jp   eMail: t-tanaka@nagasaki-u.ac.jp
,
Ryosuke Oowatashi
Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan   eMail: y-matsuo@nagasaki-u.ac.jp   eMail: t-tanaka@nagasaki-u.ac.jp
,
Yoshinori Saito
Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan   eMail: y-matsuo@nagasaki-u.ac.jp   eMail: t-tanaka@nagasaki-u.ac.jp
,
Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan   eMail: y-matsuo@nagasaki-u.ac.jp   eMail: t-tanaka@nagasaki-u.ac.jp
› Institutsangaben
This work was supported by JSPS KAKENHI Grant Numbers JP16K07741 and JP17K08338
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Publikationsverlauf

Received: 07. Juni 2017

Accepted after revision: 04. Juli 2017

Publikationsdatum:
11. August 2017 (online)


Abstract

Theaflavins are reddish-orange black tea pigments with a benzotropolone chromophore, and their various biological activities have been reported. Theaflavins are produced by oxidative coupling between catechol-type and pyrogallol-type catechins via bicyclo[3.2.1]octane-type intermediates. In this study, a new method for nonenzymatic biomimetic synthesis of theaflavins was developed using the DPPH radical as an oxidizing agent.

Supporting Information

 
  • References and Notes

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