ERROR opening https://cactus.nci.nih.gov/chemical/structure/C2CCCN2C%28C%29C%3DC%28c1sccc1%29c3sccc3/file?format=sdf&get3d=True  -- C2CCCN2C%28C%29C%3DC%28c1sccc1%29c3sccc3 could not be loaded.