ERROR opening https://cactus.nci.nih.gov/chemical/structure/%5BO-%5D%5BN%2B%5D%28C%29%28C%29CC/C%3DC2/c1c%28cccc1%29CCc3c2cccc3/file?format=sdf&get3d=True  -- %5BO-%5D%5BN%2B%5D%28C%29%28C%29CC/C%3DC2/c1c%28cccc1%29CCc3c2cccc3 could not be loaded.