ERROR opening https://cactus.nci.nih.gov/chemical/structure/CN1C2%3DCC%3DCC%3DC2C3%3DC1C%3DNC%3DC3/file?format=sdf&get3d=True  -- CN1C2%3DCC%3DCC%3DC2C3%3DC1C%3DNC%3DC3 could not be loaded.