2,3,6,7-tetramethoxy-9,10-dimethyl-9,10-dihydroanthracene InChI=1/C20H24O4/c1-11-13-7-17(21-3)19(23-5)9-15(13)12(2)16-10-20(24-6)18(22-4)8-14(11)16/h7-12H,1-6H anthracene, 9,10-dihydro-2,3,6,7-tetramethoxy-9,10-dimethyl-