172686-04-3 2H-Benzofuro(3,2-g)-1-benzopyran-2,5,11-trione, 6,7,8,9-tetrahydro-4-methyl- 6,7,8,9-Tetrahydro-4-methyl-2H-benzofuro(3,2-g)-1-benzopyran-2,5,11-trione