ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCC%28C%29C1%3DC%28C%3DC%28C%28%3DC1%29OC%29CC%28C%29N%29OC/file?format=sdf&get3d=True -- CCC%28C%29C1%3DC%28C%3DC%28C%28%3DC1%29OC%29CC%28C%29N%29OC could not be loaded.