ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C7H4N2O2/c8-9-6-3-1-2-5(4-6)7(10)11/h1-4H/file?format=sdf&get3d=True  -- InChI=1S/C7H4N2O2/c8-9-6-3-1-2-5(4-6)7(10)11/h1-4H could not be loaded.