ERROR opening https://cactus.nci.nih.gov/chemical/structure/CN%28C%29C%28C%29Cc2c%5BnH%5Dc1ccccc12/file?format=sdf&get3d=True  -- CN%28C%29C%28C%29Cc2c%5BnH%5Dc1ccccc12 could not be loaded.