ERROR opening https://cactus.nci.nih.gov/chemical/structure/c1%28c2c%28c%28ccc2%29Cl%29Cl%29c%28nc%28N%29nn1%29N/file?format=sdf&get3d=True  -- c1%28c2c%28c%28ccc2%29Cl%29Cl%29c%28nc%28N%29nn1%29N could not be loaded.