Synonyms: 2H-Cyclopenta[b]furan-2-one,3,3a,6,6a-tetrahydro-, (3aR-cis)-; (-)-(1S,5R)-2-Oxabicyclo[3.3.0]oct-6-en-3-one;(1S,5R)-2-Oxabicyclo[3.3.0]oct-6-en-3-one;(1S,5R)-2-Oxabicyclo[3.3.0]oct-6-en-3-one;(3AR,6aS)-3,3a,6,6a-tetrahydro-2H-cyclopenta[b]furan-2-one;(3aR,6aS)-3,3a,6,6a-Tetrahydro-2H-cyclopenta[b]furan-2-one