ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28Nc1c%28scc1C%29C%28%3DO%29OC%29C%28NCCC%29C/file?format=sdf&get3d=True -- O%3DC%28Nc1c%28scc1C%29C%28%3DO%29OC%29C%28NCCC%29C could not be loaded.