Nonenzymatic Biomimetic Synthesis of Black Tea Pigment Theaflavins
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.
Synthesis of Theaflavins via Biomimetic Oxidative Coupling Reactions
Biomimetic synthesis of theaflavins from catechins was accomplished by using 2-nitrobenzenesulfonyl (Ns) as a protecting group for phenols to minimize undesired side reactions of the electron-rich aromatic rings. This enabled the construction of the complex benzotropolone core in a single-step oxidative coupling reaction. Georg Thieme Verlag Stuttgart · New York.
Benzotropolone derivatives and modulation of inflammatory response
The present invention provides novel benzotropolone derivatives represented by the general formula: 1 including neotheaflavate B and EGCGCa. The benzotropolone derivatives of the present invention are effective antioxidant and anti-inflammatory agents. The present invention also provides novel method of synthesizing benzotropolone compounds in high yields and method of treating inflammatory conditions using benzotropolone containing compounds.
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(2008/06/13)
Enzymatic synthesis of tea theaflavin derivatives and their anti-inflammatory and cytotoxic activities
Derivatives based on a benzotropolone skeleton (9-26) have been prepared by the enzymatic coupling (horseradish peroxidase/H2O2) of selected pairs of compounds (1-8), one with a vic-trihydroxyphenyl moiety, and the other with an ortho-dihydroxyphenyl structure. Some of these compounds have been found to inhibit TPA-induced mice ear edema, nitric oxide (NO) synthesis, and arachidonic acid release by LPS-stimulated RAW 264.7 cells. Their cytotoxic activites against KYSE 150 and 510 human esophageal squamous cell carcinoma and HT 29 human colon cancer cells were also evaluated.
Get Best Price for31701-93-61-[(2S,3S)-3,4-Dihydro-3,5,7-trihydroxy-2H-1-benzopyran-2-yl]-8-[(2R,3S)-3,4-dihydro-3,5,7-trihydroxy-2H-1-benzopyran-2-yl]-3,4,6-trihydroxy-5H-benzocyclohepten-5-one