ERROR opening https://cactus.nci.nih.gov/chemical/structure/C1%3DC2C%28%3DCC%3DC1CC%28CCC%29NCC%29OCO2/file?format=sdf&get3d=True  -- C1%3DC2C%28%3DCC%3DC1CC%28CCC%29NCC%29OCO2 could not be loaded.