2,5-phenanthrenediol, 3,4-dimethoxy- 3,4-dimethoxyphenanthrene-2,5-diol InChI=1/C16H14O4/c1-19-15-12(18)8-10-7-6-9-4-3-5-11(17)13(9)14(10)16(15)20-2/h3-8,17-18H,1-2H