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