Theaflavin (TF) and its derivatives, known collectively as theaflavins, are antioxidant polyphenols that are formed from flavan-3-ols such as in tea leaves during the enzymatic oxidation (called fermentation by the tea trade) of tea leaves, such as in black tea. Theaflavin-3-gallate, theaflavin-3'-gallate, theaflavin-3-3'-digallate, are all types of theaflavins.

The PubChem page is [1].

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