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