ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C5H7N3/c6-5(7)4-1-2-8-3-4/h1-3H,6-7H2/file?format=sdf&get3d=True  -- InChI=1S/C5H7N3/c6-5(7)4-1-2-8-3-4/h1-3H,6-7H2 could not be loaded.