About: http://webisa.webdatacommons.org/347273318

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	Preferably, R1 and R2 are each, identically or differently, a methyl or ethyl group and R3 is a hydrogen atom or a methyl group.
http://www.w3.org/ns/prov#wasQuotedFrom	google.es