ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC1NC%28%3DO%29CCC1%28c2ccc%28N%29cc2%29CC/file?format=sdf&get3d=True  -- O%3DC1NC%28%3DO%29CCC1%28c2ccc%28N%29cc2%29CC could not be loaded.