ERROR opening https://cactus.nci.nih.gov/chemical/structure/CN1N%3DNC2%3DC%28N%3DCN2C1%3DO%29C%28N%29%3DO/file?format=sdf&get3d=True  -- CN1N%3DNC2%3DC%28N%3DCN2C1%3DO%29C%28N%29%3DO could not be loaded.