About: http://webisa.webdatacommons.org/190583174

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	For monosubstituted maleic anhydrides, R1 or R2 is a hydrogen and R2 or R1 is linked to the anhydride via a carbon-carbon bond.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com