ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28c1ccccc1%29NC4CCN%28CCc3c2ccccc2%5BnH%5Dc3%29CC4/file?format=sdf&get3d=True -- O%3DC%28c1ccccc1%29NC4CCN%28CCc3c2ccccc2%5BnH%5Dc3%29CC4 could not be loaded.