ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C15H12O6/c16-9-6-13(20)15(14(21)7-9)11(18)4-2-8-1-3-10(17)12(19)5-8/h1-7,16-17,19-21H/b4-2+/file?format=sdf&get3d=True  -- InChI=1S/C15H12O6/c16-9-6-13(20)15(14(21)7-9)11(18)4-2-8-1-3-10(17)12(19)5-8/h1-7,16-17,19-21H/b4-2+ could not be loaded.