(4aS,4bS,4'R,5aS,6aS,8S,9aS,9bS)-2',2'-Diethyl-4a,6a,8-trimethyl-6,6a,8,9,9a,9b,10,11-octahydro-2H-spiro[cyclopenta[1,2]phenanthro[4,4a-b]oxirene-7,4'-[1,3]dioxane]-2,5'(4aH,5aH)-dione