ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC1%28CCC%28CC1%29NC%28%3DO%29C%28CCC%28%3DO%29O%29N%29C/file?format=sdf&get3d=True -- CC1%28CCC%28CC1%29NC%28%3DO%29C%28CCC%28%3DO%29O%29N%29C could not be loaded.