ERROR opening https://cactus.nci.nih.gov/chemical/structure/n1c3c%28n2c%28cnc2c1NCCN%29C%29cc%28cc3%29C/file?format=sdf&get3d=True  -- n1c3c%28n2c%28cnc2c1NCCN%29C%29cc%28cc3%29C could not be loaded.