ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCC%28C%29%28C%29N%3DC%28NC%23N%29NC1%3DCN%3DCC%3DC1/file?format=sdf&get3d=True  -- CCC%28C%29%28C%29N%3DC%28NC%23N%29NC1%3DCN%3DCC%3DC1 could not be loaded.