ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC/2Oc1cc%28O%29ccc1%5CC%28%3DC%5C2%29C/file?format=sdf&get3d=True  -- O%3DC/2Oc1cc%28O%29ccc1%5CC%28%3DC%5C2%29C could not be loaded.