(2S,3R,3aR,5S,7S,7aS,9bβ)-Icosahydro-2,5-dihydroxy-3aα,4,4,5aβ,7a,9aα-hexamethyl-3α-(1-methylethyl)spiro[7H-benz[e]indene-7,1-[1H]inden]-6-one