Synonyms: Furo[3,2-b]naphtho[1,2-d]furan-3,9(2H,4H)-dione,8-ethyldecahydro-4,4,6a,10c-tetramethyl-, (4aR,6aR,7aS,8S,10aS,10bS,10cS)-(9CI); Furo[3,2-b]naphtho[1,2-d]furan-3,9(2H,4H)-dione,8-ethyldecahydro-4,4,6a,10c-tetramethyl-, [4aR-(4aa,6ab,7ab,8b,10ab,10ba,10cb)]-; (+)-Symphyogynolide; Symphyogynolide