Showing structure for (9r)-4,6,7-trihydroxy-1,8,8,9-tetramethyl-5-{[(9r)-4,6,7-trihydroxy-1,8,8,9-tetramethyl-3-oxo-9h-phenaleno[1,2-b]furan-5-yl]methyl}-9h-phenaleno[1,2-b]furan-3-one