ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28%3DCC%28%3DO%29C%29O.C/C%28%3DC/C%28%3DO%29C%29/O.O.%5BFe%5D/file?format=sdf&get3d=True  -- CC%28%3DCC%28%3DO%29C%29O.C/C%28%3DC/C%28%3DO%29C%29/O.O.%5BFe%5D could not be loaded.