ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28C%29%28C%29C1%3DNN%3DC%28S1%29N%28C%29C%28%3DO%29NC/file?format=sdf&get3d=True -- CC%28C%29%28C%29C1%3DNN%3DC%28S1%29N%28C%29C%28%3DO%29NC could not be loaded.