ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCCN%28CCC%29C1CCC2%3DC%28C1%29C%3DC%28O%29C%3DC2/file?format=sdf&get3d=True -- CCCN%28CCC%29C1CCC2%3DC%28C1%29C%3DC%28O%29C%3DC2 could not be loaded.