ERROR opening https://cactus.nci.nih.gov/chemical/structure/C1%3DCC2%3DC3C%28%3DC1%29C%3DCC3%3DCC%3DC2/file?format=sdf&get3d=True  -- C1%3DCC2%3DC3C%28%3DC1%29C%3DCC3%3DCC%3DC2 could not be loaded.