ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28C%29%28C1%3DCN%3DCC%3DC1%29C%28%3DO%29C2%3DCN%3DCC%3DC2/file?format=sdf&get3d=True  -- CC%28C%29%28C1%3DCN%3DCC%3DC1%29C%28%3DO%29C2%3DCN%3DCC%3DC2 could not be loaded.