ERROR opening https://cactus.nci.nih.gov/chemical/structure/OC/C%3DC/c1cc%28OC%29c%28O%29c%28OC%29c1/file?format=sdf&get3d=True  -- OC/C%3DC/c1cc%28OC%29c%28O%29c%28OC%29c1 could not be loaded.