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 member of the class of cyclobutadipyrimidines that is 1,4a,4b,8,8a,8b-hexahydrocyclobuta[1,2-d:4,3-d']dipyrimidine-2,7-dione carrying two additional amino substituents at positions 4 and 5.