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 3-oxo-5alpha-steroid that is 5alpha-estrane which is substituted by an oxo group at position 3, a hydroxy group at the 17beta position, and which has a double bond between positions 1 and 10. It is a 19-norsteroid arising from successive oxidation of dihydrotestosterone at C19.