ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C3H4N2/c1-2-5-3-4-1/h1-3H,(H,4,5)/file?format=sdf&get3d=True -- InChI=1S/C3H4N2/c1-2-5-3-4-1/h1-3H,(H,4,5) could not be loaded.