ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCOC1%3DCC2%3DC%28C%3DC1%29N%28C3C2%28CCN3C%29C%29C/file?format=sdf&get3d=True -- CCOC1%3DCC2%3DC%28C%3DC1%29N%28C3C2%28CCN3C%29C%29C could not be loaded.