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