ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/C8H20N4/c1-2-10-5-6-12-8-7-11-4-3-9-1/h9-12H%2C1-8H2/file?format=sdf&get3d=True  -- InChI%3DInChI%3D1S/C8H20N4/c1-2-10-5-6-12-8-7-11-4-3-9-1/h9-12H%2C1-8H2 could not be loaded.