ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28OCC%29NNc1nnc%28N%28CC%28O%29C%29CC%29cc1/file?format=sdf&get3d=True  -- O%3DC%28OCC%29NNc1nnc%28N%28CC%28O%29C%29CC%29cc1 could not be loaded.