About: http://webisa.webdatacommons.org/402569494

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	In view of the effects of the present invention, it is particularly preferred that each of R1, R2, R3 and R4 is a methyl group.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com