ERROR opening https://cactus.nci.nih.gov/chemical/structure/C%3DCCOC1%3DNC%28%3DNC%28%3DN1%29OCC%3DC%29OCC%3DC/file?format=sdf&get3d=True  -- C%3DCCOC1%3DNC%28%3DNC%28%3DN1%29OCC%3DC%29OCC%3DC could not be loaded.