ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC1Oc3c2c4c1cc%28O%29c%28O%29c4OC%28%3DO%29c2cc%28O%29c3O/file?format=sdf&get3d=True  -- O%3DC1Oc3c2c4c1cc%28O%29c%28O%29c4OC%28%3DO%29c2cc%28O%29c3O could not be loaded.