ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCC1%3DC%28C%3DC%28OC1%3DO%29C%28C%29CC%29O/file?format=sdf&get3d=True  -- CCC1%3DC%28C%3DC%28OC1%3DO%29C%28C%29CC%29O could not be loaded.