The Chemical Entities of Biological Interest (ChEBI) ontology is downloaded weekly from EMBL-EBI at http://www.ebi.ac.uk/chebi/. The data is made available under the Creative Commons License (CC BY 3.0, http://creativecommons.org/licenses/by/3.0/). For more information see: Degtyarenko et al. (2008) ChEBI: a database and ontology for chemical entities of biological interest. Nucleic Acids Res. 36, D344–D350.
A organic heterotetracyclic compound that is 10H-benzo[b]xanthene-7,10,12-trione substituted by hydroxy groups at positions 6 and 11, methoxy groups at positions 3 and 8 and a methyl group at position 1.