ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28O%29C%28C%28%3DO%29N%28Nc1ccccc1%29c2ccccc2%29CCCC/file?format=sdf&get3d=True  -- O%3DC%28O%29C%28C%28%3DO%29N%28Nc1ccccc1%29c2ccccc2%29CCCC could not be loaded.