Tetrahydroaltersolanol B, a hexahydroanthronol from Alternariasolani

The structure of a novel reduced anthraquinone, isolable in small amounts from culture filtrates of the fungus, Alternariasolani, is shown to be 6a mainly by spectroscopic methods. Detailed examination of the 1Hmr spectra of 6a has defined its stereochemistry; the 13Cmr spectral data for 6a and several derivatives are also reported.