ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC1CC%28N%29%3DNN1C%28C%29c2cc%28Cl%29c%28Cl%29cc2/file?format=sdf&get3d=True  -- O%3DC1CC%28N%29%3DNN1C%28C%29c2cc%28Cl%29c%28Cl%29cc2 could not be loaded.