ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28C%29CC1%3DC%28C%3DC%28C%28%3DC1%29OC%29CCN%29OC/file?format=sdf&get3d=True  -- CC%28C%29CC1%3DC%28C%3DC%28C%28%3DC1%29OC%29CCN%29OC could not be loaded.