ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC%28c1c2ccccc2nc%28OCCCC%29c1%29NCCN%28CC%29CC/file?format=sdf&get3d=True  -- O%3DC%28c1c2ccccc2nc%28OCCCC%29c1%29NCCN%28CC%29CC could not be loaded.