ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28NCC%28O%29c1cc%28OC%29ccc1OC%29CN/file?format=sdf&get3d=True  -- O%3DC%28NCC%28O%29c1cc%28OC%29ccc1OC%29CN could not be loaded.