Biomimeticsynthesis 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 oxidativecoupling reaction.
An efficient and versatile synthetic method for labile polyphenols was established using 2-nitrobenzenesulfonate (Ns) as a protectinggroup for phenol. This methodology provides regio- and stereoselective access to a range of methylated catechins, such as methylated epigallocatechin gallates, that are not readily available from natural sources. In addition, biomimetic synthesis of theaflavins from