ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28OC1C%28N%29C%28O%29OC%28CO%29C1O%29C%28O%29%3DO/file?format=sdf&get3d=True  -- CC%28OC1C%28N%29C%28O%29OC%28CO%29C1O%29C%28O%29%3DO could not be loaded.