About: http://webisa.webdatacommons.org/130756274

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, A is an oxygen atom, B has two carbons, R2 and R3 are methyl or ethyl, and R4 is methyl, ethyl, or benzyl.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com