ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC1C2%3DCC%28%3DC%28C%3DC2CCN1C%29OC%29OC/file?format=sdf&get3d=True  -- CC1C2%3DCC%28%3DC%28C%3DC2CCN1C%29OC%29OC could not be loaded.