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.
An epoxide that is oxiran-2-ylmethanol which is acylated at position 2 by N-butanoyl-L-seryl-4-methylidenenorvalinyl group. It is a proteasome inhibitor isolated from Streptomyces.