Tyrosinase catalysed biphenyl construction from flavan-3-ol substrates

Abstract Mushroom tyrosinase catalysed oxidation of three flavan-3-ols, viz. catechin, fisetinidol and mesquitol, was conducted to construct biphenyl bonds. Exposure of the flavan-3-ols to tyrosinase and subsequent trapping of the o -quinone intermediates resulted in the formation of novel flavan-3-ol derivatives, the structures of which were elucidated by mono- and two-dimensional 1 H -NMR experiments. Application of the methodology resulted in the improved synthesis of the natural flavan-3-ol dimer, mesquitol-[5 → 8]-catechin, previously isolated from Prosopis glandulosa .