ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/C6H18N4/c7-1-3-9-5-6-10-4-2-8/h9-10H%2C1-8H2/file?format=sdf&get3d=True  -- InChI%3DInChI%3D1S/C6H18N4/c7-1-3-9-5-6-10-4-2-8/h9-10H%2C1-8H2 could not be loaded.