revised structure of wasabidienone-A from a potato culture of Phoma wasabiae Yokogi

Recently the authors reported the isolation and the structure of a new natural cyclohexadienone derivative, wasabidienone-A, from the potato culture solution of Phoma wasabiae Yokogi. The proposed structure was a tautomeric mixture of 3-hydroxy-5-methoxy-2,6-dimethyl-6-(2-methylbutyryloxy)-2,4-cycloh exadien-1-one and 3-hydroxy-5-methoxy-2,4-dimethyl-4-(2-methylbutyryloxy)-2,5-cycloh exadien-1-one. To confirm unequivocally the structure and stereochemistry of wasabidienone-A, its p-nitrobenzoate derivative was analysed by the single crystal X-ray method.