ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC1C%28C%28C%29C%29%3DC%28C%29N%28C%29N1c2ccccc2/file?format=sdf&get3d=True  -- O%3DC1C%28C%28C%29C%29%3DC%28C%29N%28C%29N1c2ccccc2 could not be loaded.