ERROR opening https://cactus.nci.nih.gov/chemical/structure/CN1C2%3DCC%3DCC%3DC2N%3DC3C1%3DCC%3DCC3%3DO/file?format=sdf&get3d=True  -- CN1C2%3DCC%3DCC%3DC2N%3DC3C1%3DCC%3DCC3%3DO could not be loaded.