ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28O%29c1c3ccccc3nc%28c1%29c2ccccc2/file?format=sdf&get3d=True  -- O%3DC%28O%29c1c3ccccc3nc%28c1%29c2ccccc2 could not be loaded.