ERROR opening https://cactus.nci.nih.gov/chemical/structure/C1%28%3DC%28C%28%3DC%28C%28%3DC1I%29I%29I%29I%29I%29I/file?format=sdf&get3d=True  -- C1%28%3DC%28C%28%3DC%28C%28%3DC1I%29I%29I%29I%29I%29I could not be loaded.