Biosynthesis and Stereochemistry of Phlegmacin-Type Fungal Pigments

The absolute stereostructures of phlegmacins A1 (3a) and B1 (3b) were determined by biosynthetic studies, quantum chemical CD calculations, and NOE experiments. In Cortinarius odorifer these compounds are formed by regioselective oxidative dimerization of (R)-torosachrysone (R-2). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)