ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCCN1CCCC%28C1%29C2%3DCC%28%3DCC%3DC2%29O/file?format=sdf&get3d=True  -- CCCN1CCCC%28C1%29C2%3DCC%28%3DCC%3DC2%29O could not be loaded.