ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28NCCCN%28O%29CCCNCCCNCCCCNCCCN%29Cc2c1ccccc1nc2/file?format=sdf&get3d=True  -- O%3DC%28NCCCN%28O%29CCCNCCCNCCCCNCCCN%29Cc2c1ccccc1nc2 could not be loaded.