ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCCCCCCCCCCC%28%3DO%29c1ccc2cc%28ccc2c1%29N%28C%29C/file?format=sdf&get3d=True  -- CCCCCCCCCCCC%28%3DO%29c1ccc2cc%28ccc2c1%29N%28C%29C could not be loaded.