ERROR opening https://cactus.nci.nih.gov/chemical/structure/c12c%28%5BnH%5Dcc1CC%28O%29%3DO%29cccc2/file?format=sdf&get3d=True  -- c12c%28%5BnH%5Dcc1CC%28O%29%3DO%29cccc2 could not be loaded.