ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/CH4N4O4/c6-4%287%292-1-3-5%288%299/h2-3H%2C1H2/file?format=sdf&get3d=True  -- InChI%3DInChI%3D1S/CH4N4O4/c6-4%287%292-1-3-5%288%299/h2-3H%2C1H2 could not be loaded.