ERROR opening https://cactus.nci.nih.gov/chemical/structure/N%28%3DO%29%28%3DO%29c%28ccc%28c1%29Cl%29c1/file?format=sdf&get3d=True  -- N%28%3DO%29%28%3DO%29c%28ccc%28c1%29Cl%29c1 could not be loaded.