ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC1%3DCC%28%3DC%28C%3DC1%29C%28C%29C%29O/file?format=sdf&get3d=True  -- CC1%3DCC%28%3DC%28C%3DC1%29C%28C%29C%29O could not be loaded.