About: http://webisa.webdatacommons.org/397091439

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	When they are not hydrogen atoms then R1 and R2 are preferably hydrocarbyl groups i.e. contain no atoms other than hydrogen and carbon, although R1 and R2 may if desired contain other atoms, e.g. oxygen or nitrogen atoms.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com