ERROR opening https://cactus.nci.nih.gov/chemical/structure/CN%28C%29CCOc1ccccc1c2nc%28no2%29c3ccccc3/file?format=sdf&get3d=True  -- CN%28C%29CCOc1ccccc1c2nc%28no2%29c3ccccc3 could not be loaded.