ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28OCCC%28C%29C%29C%28NCCN%28CC%29CC%29c1ccccc1/file?format=sdf&get3d=True  -- O%3DC%28OCCC%28C%29C%29C%28NCCN%28CC%29CC%29c1ccccc1 could not be loaded.