Author's Organization:Faculty of Pharmaceutical Sciences Kyoto University Faculty of Pharmaceutical Sciences Kyoto University Faculty of Pharmaceutical Sciences Mukogawa Women's University Faculty of Pharmaceutical Sciences Mukogawa Women's University
E-and Z-forms of 10, 11-dihydroatlantone and its 6-oxo-compound were newly isolated in optically inactive form from heart wood of Ginkgo biloba L. These structures were confirmed by synthesis stating from limonene.