ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%28c1cc%28NC%28C%29CCCN%29c2ncccc2c1%29C/file?format=sdf&get3d=True  -- O%28c1cc%28NC%28C%29CCCN%29c2ncccc2c1%29C could not be loaded.