Brevione C

3,4a,6′,7,7′,11a-Hexamethyl-4a,5,6,6a,11a,11b-hexahydro-3′H,4′H-spiro[cyclohepta[a]naphthalene-4,2′-furo[3,2-c]pyran]-4′,9(1H)-dione

Brevione C

Spiro[4H-cyclohepta[a]naphthalene-4,2′(3′H)-[4H]furo[3,2-c]pyran]-4′,9(1H)-dione, 4a,5,6,6a,11a,11b-hexahydro-3,4a,6′,7,7′,11a-hexamethyl-