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