Ethisolide

(3aβ,6aβ)-3-Methylene-4α-ethylhexahydrofuro[3,4-b]furan-2,6-dione

(-)-3aβ,6aβ-Dihydro-3-methylene-4α-ethylfuro[3,4-b]furan-2,6(3H,4H)-dione

(3aR)-4α-Ethyl-3aβ,6aβ-dihydro-3-methylenefuro[3,4-b]furan-2,6(3H,4H)-dione